Association between masticatory function and Parkinson’s disease: A population-based study

Association between masticatory function and Parkinson’s disease: A population-based study | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Association between masticatory function and Parkinson’s disease: A population-based study Ziyang Zheng, Jiaqi Wu This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7634776/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Masticatory dysfunction may contribute to systemic diseases, including Parkinson’s disease (PD), but evidence from large populations is limited. Using data from 37,668 adults in NHANES 1999–2018, we assessed mastication with functional tooth units (FTUs), and defined PD by medication use. Logistic regression, restricted cubic spline (RCS), and stratified analyses were applied with adjustment for demographic, socioeconomic, lifestyle, and health covariates, and sensitivity analyses were performed. Among participants, 334 had PD (weighted prevalence 0.8%). Mean FTUs (5.70 vs. 8.31) and tooth counts (19.09 vs. 23.13) were significantly lower in PD than non-PD individuals (P < .001). Each unit increase in FTU was associated with reduced PD risk (OR = 0.923, 95% CI 0.879–0.969), and participants with FTU 10–12 had 48% lower PD prevalence (OR = 0.518, 95% CI 0.298–0.901). Molar FTU and tooth counts were inversely associated with PD, while masticatory dysfunction and incomplete dentition were linked to higher risk. RCS suggested a linear association, with stronger effects observed in older, non-diabetic, and non-hypertensive individuals (P for interaction < 0.05). Sensitivity analyses confirmed the robustness of findings. These results indicate that better mastication, reflected by higher FTUs, is associated with reduced PD risk, highlighting the potential role of oral health maintenance in PD prevention and management. Health sciences/Diseases Health sciences/Health care Health sciences/Medical research Health sciences/Neurology Health sciences/Risk factors Masticatory function functional tooth unit Parkinson’s disease NHANES. Figures Figure 1 Figure 2 1. Introduction Characterized by degeneration of the substantia nigra pars compacta and by accumulation of α-synuclein in Lewy bodies, Parkinson’s disease (PD), is the second common but complex progressive neurodegenerative disease 1 . Motor symptoms include tremor and bradykinesia, and nonmotor motor impairments include disorder of mood, sleep, sensation, cognition and autonomic function, both of which are preceding the motor signs 2 . The global prevalence of PD is in growth with 1.51 cases per 1000, and those countries with high sociodemographic levels were prominent 3 , and those in lower to upper-middle-income countries were more pronounced 4 . The age-standardized disability-adjusted life-year was observed largest in PD 5 . In 2050, the prevalence was projected to at 267 per 100 000, and aging was projected to be the primary contributor 6 . Risk factors for PD include positive association with the history of anxiety or depression, pesticide exposure, head injury, rural living, β blockers, farming occupation, and well-water drinking while negative with coffee drinking, hypertension, nonsteroidal anti-inflammatory drugs, calcium channel blockers, and alcohol 7 . Patients with PD commonly experienced chewing difficulties, denture discomfort, loss of natural teeth, poor oral hygiene, and swallowing problems 8 . The self-assessed oral health-related quality of life (OHRQoL) was impaired by the oral symptoms including xerostomia, drooling and dysphagia in those with PD, however, they reported adequate dental health care 9 . Moreover, motor aspects of experiences of daily living of PD related variable were correlated with the OHRQoL, and oral health related variables were also related including the oral environment ailment during disease course, being dentate, tooth wear and burning mouth syndrome 10 . Then, PD may be a possible factor in periodontal health breakdown 11 . The masticatory and orofacial function are impaired in those with moderate to advanced PD, and these problems become marked with the progression of PD 12 . Noted, PD was associated with impaired masticatory function, specifically the range of jaw motion, longer duration, slower velocity of masticatory cycle and lower maximum bite force 13 . Conversely, oral health is associated with PD. Patients with temporomandibular disorder was in higher risk of PD development, and vice versa 14 . Those with exposure to dental amalgam fillings were more susceptible to PD compared to those non-exposed 15 . Then, paining gums is correlated with increased susceptibility of PD based on UK biobank 16 . Periodontal inflammatory disease (PID) was also associated with PD development 17 . Moreover, the number of tooth loss was positively associated with higher risk of new-onset PD development 18 . Influenced by the periodontal status, tooth counts and functional teeth, masticatory function is closely correlated with general health conditions 19 . Considering that masticatory ability is associated with cognition 20 and depression 21 , both of which are risk for the PD. With the expanding economic and health burden of neurodegenerative diseases, the multidisciplinary approaches for addressing risk factors verifications and the unmet medical and social need is urgent needed 22 . There may be an association between masticatory performance with PD. As this area remains insufficiently explored, further study into the association between masticatory function and the risk of PD in a nationally representative sample is warranted. Hence, this aim of this study examines the association between masticatory function and the risk of PD using data from the NHANES, offering new insights to oral alterations of alert or progression of PD and preservation of ideal mastication for the prevention and management of individuals with PD. 2. Results 2.1 Basic characteristics of study population The flow chart of participants inclusion is illustrated in Fig. 1 . In the primary analysis, 37,668 participants were included, among whom 334 were diagnosed with PD, yielding a weighted prevalence of 0.8%. After adjusting for additional covariates, the secondary analysis comprised 34,941 participants, of whom 312 were diagnosed with PD, corresponding to a prevalence of 0.83%. Baseline characteristics of participants is presented in Table 1 according to PD status and the baseline by FTU subgroups is presented in Table S1 . The mean FTU values were 5.70 for individuals with PD and 8.31 for those without PD, while the mean number of teeth was 19.09 and 23.13, respectively. Both differences were statistically significant. The baseline of the secondary analysis is presented in Table S2. Table 1 Baseline characteristics according to the presence of PD in the primary analyses. Variable Total Non-PD PD P -value Age (year) 47.33(0.21) 47.25(0.21) 56.87(1.06) < .001 Tooth number 23.10(0.11) 23.13(0.11) 19.09(0.75) < .001 FTU 8.29(0.06) 8.31(0.06) 5.70(0.35) < .001 Gender 0.01 Female 18559(50.49) 18387(50.42) 172(59.35) Male 19109(49.51) 18947(49.58) 162(40.65) Race 0.03 Mexican American 6228(7.48) 6189(7.50) 39(4.28) Non-Hispanic Black 7738(10.34) 7686(10.35) 52(8.72) Non-Hispanic White 17605(70.88) 17400(70.81) 205(79.28) Other Hispanic 2893(5.11) 2869(5.13) 24(3.58) Other Race 3204(6.19) 3190(6.21) 14(4.14) Education level 0.21 Below high school 9473(15.87) 9370(15.83) 103(20.17) High school 8733(23.92) 8663(23.91) 70(24.92) Above high school 19462(60.21) 19301(60.26) 161(54.91) Poverty .001 Low income 11062(20.11) 10940(20.05) 122(27.99) Moderate income 14422(35.71) 14293(35.68) 129(39.75) High income 12184(44.17) 12101(44.27) 83(32.26) Marital status 0.01 Married/Living with Partner 22873(64.53) 22691(64.57) 182(59.97) Widowed/Divorced/Separated 8502(18.62) 8402(18.55) 100(27.15) Never married 6293(16.84) 6241(16.88) 52(12.88) Body mass index 0.18 Normal 11053(30.86) 10965(30.87) 88(28.84) Overweight 12795(33.37) 12700(33.41) 95(28.65) Obese 13820(35.78) 13669(35.72) 151(42.51) Smoke 0.32 Never 20036(53.34) 19877(53.34) 159(52.70) Former 9645(25.35) 9552(25.37) 93(22.32) Now 7987(21.32) 7905(21.29) 82(24.98) Alcohol consumption < .001 Never 5212(10.93) 5165(10.92) 47(13.02) Former 6639(14.37) 6539(14.29) 100(24.90) Mild 12795(36.52) 12678(36.52) 117(37.19) Moderate 5640(17.22) 5615(17.29) 25(9.31) Heavy 7382(20.95) 7337(20.99) 45(15.58) Diabetes < .001 No 31841(88.79) 31594(88.86) 247(80.43) Yes 5827(11.21) 5740(11.14) 87(19.57) Hypertension < .001 No 21432(62.47) 21291(62.60) 141(46.53) Yes 16236(37.53) 16043(37.40) 193(53.47) CVD < .001 No 33475(91.40) 33228(91.50) 247(79.60) Yes 4193(8.60) 4106(8.50) 87(20.40) Functional dentition < .001 No 9455(17.70) 9318(17.56) 137(34.79) Yes 28213(82.30) 28016(82.44) 197(65.21) Masticatory dysfunction < .001 No 25655(76.75) 25497(76.94) 158(53.95) Yes 12013(23.25) 11837(23.06) 176(46.05) Complete dentition < .001 No 25783(60.65) 25494(60.48) 289(82.05) Yes 11885(39.35) 11840(39.52) 45(17.95) 2.2 Associations between masticatory functions with PD The correlation between FTU and PD is detailed in Table 2 . In the fully adjusted model, each one-unit increase in FTU was associated with a 7.7% lower prevalence of PD (OR = 0.923, 95% CI 0.879–0.969, P = 0.002), and those having an FTU score of 10–12 was associated with a 48.2% lower prevalence of PD (OR = 0.518, 95% CI 0.298–0.901, P = 0.020). Higher FTU values were associated with a reduced risk of PD ( P for trend < 0.05). As shown in Table 3 , molar FTU (OR = 0.884, 95% CI 0.825–0.948, P < 0.001) and tooth counts (OR = 0.978, 95% CI 0.956-1.000, P = 0.048) were associated with a lower risk of PD, whereas masticatory dysfunction (OR = 1.820, 95% CI 1.172–2.826, P = 0.008) and incomplete dentition (OR = 2.017, 95% CI 1.312–3.101, P = 0.002) were linked to an increased risk of PD. However, no significant associations were found between premolar FTU and functional dentition with PD. Table 2 Association between FTU and PD in the primary analyses. Variables Model I Model II Model III Continuous FTU OR[CI] P OR[CI] P OR[CI] P 0.889(0.864,0.915) < .001 0.916(0.877,0.957) < .001 0.923(0.879,0.969) 0.002 Categorical 0–3 Reference 4–6 1.161(0.796,1.693) 0.435 1.320(0.887,1.965) 0.169 1.384(0.930,2.060) 0.108 7–9 0.380(0.238,0.608) < .001 0.470(0.286,0.772) 0.003 0.511(0.305,0.856) 0.011 10–12 0.320(0.227,0.452) < .001 0.472(0.285,0.782) 0.004 0.518(0.298,0.901) 0.020 P for trend < .001 < .001 0.004 Abbreviations: FTU: functional teeth unit; PD: Parkinson’s disease. Weighted multivariable logistic regression analyses were performed with FTU as the main independent variable. Odds ratios (ORs) were calculated to evaluate the association between FTU and PD across Model I (no adjustment), Model II (adjustments of age, race/ethnicity, sex, poverty level, education, and marital status), and Model III (fully adjustments of all covariates). Table 3 Association between masticatory parameters and PD in the primary analyses. Variables Model I Model II Model III OR[CI] P OR[CI] P OR[CI] P Premolar FTU 0.764(0.706,0.828) < .001 0.866(0.774,0.967) 0.011 0.892(0.794,1.002) 0.054 Molar FTU 0.845(0.809,0.882) < .001 0.877(0.824,0.933) < .001 0.884(0.825,0.948) < .001 Tooth counts 0.953(0.941,0.966) < .001 0.972(0.952,0.993) 0.009 0.978(0.956,1.000) 0.048 Masticatory dysfunction 2.847(2.120,3.824) < .001 1.985(1.334,2.954) < .001 1.820(1.172,2.826) 0.008 Functional dentition 0.399(0.297,0.536) < .001 0.623(0.418,0.931) 0.021 0.692(0.453,1.057) 0.088 Complete dentition 2.987(2.069,4.311) < .001 2.128(1.407,3.218) < .001 2.017(1.312,3.101) 0.002 Abbreviations: FTU: functional teeth unit; PD: Parkinson’s disease. Weighted multivariable logistic regression analyses were performed with masticatory parameters as the main independent variable. Odds ratios (ORs) were calculated to evaluate the association between masticatory parameters and PD across Model I (no adjustment), Model II (adjustments of age, race/ethnicity, sex, poverty level, education, and marital status), and Model III (fully adjustments of all covariates). 2.3 Sensitivity analyses Sensitivity analyses were conducted in the secondary analysis by further adjustments of CKD, hyperlipidemia, SII, and HEI score (Table 4 ). FTU (OR = 0.928, 95% CI 0.875–0.985, P = 0.015) was associated with lower risk of DR, while masticatory dysfunction (OR = 1.759, 95% CI 1.046–2.957, P = 0.033) and incomplete dentition (OR = 2.121, 95% CI 1.311–3.431, P = 0.002) were with an increased risk of DR. FTU score of 10–12 was slightly associated with the risk of PD (OR = 0.509, 95% CI 0.259–1.003, P = 0.051). These results further reinforced the robustness of the relationship between mastication and PD. Table 4 Sensitivity analyses (Association between masticatory function and PD in the second analyses). 0–3/ Reference Variables FTU 4–6 7–9 10–12 OR[CI] 0.928(0.875,0.985) 0.958(0.583,1.572) 0.594(0.302,1.170) 0.509(0.259,1.003) P 0.015 0.863 0.131 0.051 Variables Tooth counts Masticatory dysfunction Functional dentition Complete dentition OR[CI] 0.979(0.951,1.008) 1.759(1.046,2.957) 0.686(0.410,1.146) 2.121(1.311,3.431) P 0.151 0.033 0.149 0.002 Abbreviations: FTU: functional teeth unit; PD: Parkinson’s disease. Weighted multivariable logistic regression analyses were performed with masticatory functions as the main independent variable. Odds ratios (ORs) were calculated to evaluate the association between masticatory functions and PD across Model I (no adjustment), Model II (adjustments of age, race/ethnicity, sex, poverty level, education, and marital status), and Model III (fully adjustments of all covariates). 2.4 RCS and stratified analyses Non-linear relationship was detected by RCS analyses. In the relationship between FTU and PD (Figs. 2 ), a linear relationship between FTU and DR was found ( P for nonlinearity = 0.0661). Stratified analyses were conducted to assess the stability of the relationship between FTU and PD across different subgroups (Table 5 ). The results indicated that this relationship remained stable in all subgroups except for age, DM, and hypertension (P for interaction < 0.05). Specifically, the association was consistent in individuals aged over 60 (OR = 0.934, 95% CI 0.888–0.981), those without DM (OR = 0.916, 95% CI 0.868–0.967), and those without hypertension (OR = 0.858, 95% CI 0.798–0.922). Table 5 Stratified analyses of FTU on PD. Character 95% CI P P for interaction Age 0.015 30–45 0.870(0.783, 0.967) 0.010 45–60 0.962(0.889, 1.042) 0.339 > 60 0.934(0.888,0.981) 0.007 Gender 0.395 Male 0.949(0.894,1.007) 0.084 Female 0.912(0.854,0.975) 0.007 Education level 0.314 Below high school 0.975(0.907,1.049) 0.496 High school 0.899(0.808, 1.001) 0.052 Above high school 0.921(0.869,0.976) 0.006 Poverty 0.62 Low income 0.935(0.862,1.015) 0.109 Moderate income 0.909(0.848,0.975) 0.008 High income 0.942(0.860, 1.031) 0.191 Body mass index 0.905 Normal 0.954(0.876, 1.038) 0.269 Overweight 0.892(0.818,0.973) 0.010 Obese 0.936(0.876,1.001) 0.052 Smoke 0.248 Never 0.951(0.890,1.016) 0.133 Former 0.822(0.742,0.910) < .001 Now 0.954(0.876,1.038) 0.272 Alcohol consumption 0.202 Never 0.942(0.829, 1.069) 0.351 Former 0.990(0.926, 1.057) 0.757 Mild 0.903(0.837,0.974) 0.009 Moderate 0.775(0.665, 0.902) 0.001 Heavy 0.960(0.859,1.074) 0.476 DM 0.013 No 0.916(0.868,0.967) 0.002 Yes 0.975(0.906,1.049) 0.498 Hypertension < .001 No 0.858(0.798,0.922) < .001 Yes 0.991(0.941,1.044) 0.736 CVD 0.105 No 0.929(0.883,0.977) 0.005 Yes 0.945(0.863,1.035) 0.223 Abbreviations: CVD: cardiovascular diseases; FTU: functional teeth unit; PD: Parkinson’s disease. 3. Discussion In the present study, the relationship between masticatory function and the risk of PD was unveiled. These findings suggest that the maintenance of masticatory function is beneficial to PD prevalence and progression. Poor mastication may be an alert of PD incidence and progression, and good oral hygiene, routine oral healthcare and the restoration of missing teeth and caries may be preventable for PD incidence and progression. This study aligns with previous research, indicating that oral health may influence both the prevalence and severity of PD. Regarding the effects of PD on oral health, PD patients showed less interdental hygiene, higher plaque index, higher risk of drooling, hyposialia, dysphagia and chewing difficulty 23 . All evaluated periodontal parameters deteriorated with the severity of PD, the prevalence of periodontal description was high even in the early stages of PD 24 . Then, the frequency of untreated dental caries and tooth loss was significantly higher than those without PD 25 . Also, patients with PD complained about xerostomia, which was underestimated by themselves compared with healthy 26 . PD patients had poor oral health status and decreased oral health care, the PD duration and severity were correlated with chewing problems 27 . Advanced PD stage was associated with poor periodontal health, and motor impairment was associated with increased number of untreated caries, poor oral hygiene and periodontal status, difficulties of chewing and swallowing were common in those with more decayed teeth 28 . However, these conditions of poor oral health are mostly preventable 29 . Regarding the masticatory dysfunction of PD patients. The progression of motor dysfunction in patients with PD had an effect on the chewing speed, which may be correlated with the nutritional decline 30 . PD patients had objective and subjective poor orofacial function including limitation of jaw mobility and function and mastication 31 . Those with PD had impaired masticatory function during the levodopa on-period and the mastication was worse in off-period 13 , 32 . After odontological treatment, the jaw opening, chewing time and hygiene were significantly improved in those PD participants, suggesting that simple measures like dental hygiene instruction, training of jaw opening, lip and chewing exercise could delay the PD progression 33 . Standardized exercise of jaw and orofacial muscles with individualized oral hygiene programme also resulted in improved orofacial function and OHRQoL 34 . Then, in those with PD stage 2 to 4 without prandial dysphagia, gum chewing may increase swallow frequency and decrease latency of swallowing 35 . Moreover, after the insertion of removable prostheses, the masticatory efficiency (ME) of PD patients was improved, though the was similar but the ME in PD was less than the control 36 . Then, there was a weak association between periodontitis and PD from the National Health Insurance Service of South Korea, this relationship was prominent when PD combining with metabolic syndrome 37 . Individuals without PID who underwent the dental scaling over five consecutive years had a lower risk of developing PD 38 . These evidence were aligned with the findings that tooth loss was a predictor of new-onset PD 18 when considering that periodontal status and tooth counts are closely correlated with mastication. Mechanisms under in the association between masticatory function and PD remained unclear, but the potential hypotheses may be accounted by nutritional status, orofacial function, neuroinflammation and oral microbiome 39 . First, masticatory function is closely related with food and nutrient intake, leading to decrease of diet quantity and quality, subsequently to the undernutrition 40 . Mastication measured is correlated with nutritional status 41 including plasma albumin levels, BMI in the females 42 and calf circumference in the elderly 43 . Meantime, the prevalence of malnutrition and nutritional disorders were 8.89% and 42.3% 44 . Serum albumin was decreased in those with PD and could be an independent risk factor for PD 45 . Then, it was associated with lower risk of severe motor impairment and PD-related death in those with PD 46 . Mastication may correlate with PD by the nutritional status, and this may be attributed to serum albumin levels. Then, continuous local and systemic inflammation is consistently associated with the pathophysiology of PD 47 . PD patients exhibited significant alterations of peripheral and cerebrospinal fluid inflammatory biomarkers 48 . Periodontitis is characterized by systemic inflammation, which could induce the neuroinflammation through the disruption of blood-brain barrier 49 , thus inhibiting the clearance of pathogenic substances and enhancing immune cell infiltration in periodontitis mice 50 . Then, by gentle mastication, the diseased periodontium could release bacterial pro-inflammatory biomarkers into bloodstream, which was correlated with the periodontitis severity 51 . Hence, periodontal status may be linked to Parkinson's disease (PD) through systemic inflammation induced by periodontal pathogens, while masticatory function could exacerbate neuroinflammation. Lastly, oral microbiome may play a vital role in the PD pathology. In patients with PD, higher abundance of pathogenic oral bacteria were found, revealing that oral dysbiosis is implicated in the onset and progression of PD 52 . PD may modify the subgingival microbiome and local inflammation expression 53 , 54 . Then, the dysphagia measured by swallowing disturbance questionnaire (SDQ) was negatively correlated with the oral bacterial counts (OBC) while positive with the disease duration and PD scale, those with lower SDQ showed higher OBC, and OBC was correlated with levodopa daily dose 55 . Patients with PD exhibited significant different soft tissue β diversity to the controls, which may be partially attributed to dysphagia, drooling, and salivary pH, and the abundance of opportunistic pathogens were detected 56 . Hence, oral microbiome dysbiosis plays an integral role in PD pathology. This is the first study that investigates the relationship between FTU and PD in a large nationally representative sample. Then, several sensitivity analyses and PSM further substantiate the findings. Moreover, mastication measurements by using FTU are easy and quick. Despite the strengths, several limitations should be acknowledged. First, the cross-sectional design precludes the ability to establish a causal relationship between FTU and PD due to the poor oral health may be after the PD. Second, although potential confounders were relatively comprehensively adjusted for, unmeasured factors effects on these relationships could not be completely ruled out. Third, PD was identified based on self-reported medication questionnaires, which may introduce recall bias. Additionally, FTU was measured solely by the presence of teeth rather than occlusion. The diagnosis of PD should consider both clinical symptoms and disease severity, and an objective assessment of masticatory function requires further quantification. This study addresses this gap of mastication function measured by FTU and its effect on PD, encouraging more standardized and innovative methods to re-examine the relationship of mastication and multiple neurodegenerative disorders. Future integration of dental professionals, included preventive oral health plans, oral hygiene education and oral emergency reaction, could improve the QoL and delay the progression of PD 57 . Moreover, studies involving diverse regional populations, with prospective designs, large sample sizes, and a focus on the mechanisms linking oral health and PD, are essential to validate the relationship and postulated hypotheses between FTU and PD in this study. 4. Conclusion This study demonstrates an inverse association between masticatory function and the risk of PD in a nationally representative US population. The findings underscore the potential of FTU as a practical tool for the prevention and management assessment of PD, with possible applicability to other neurodegenerative diseases. These results suggest that preserving masticatory function may benefit neurological health. 5. Methods 5.1 Study population and design Conducted by the National Center for Health Statistics (NCHS) of the Centers for Disease Control and Prevention (CDC), NHANES is an ongoing multistage program that evaluates the general health and nutritional status of participants in the United States. The Ethics Review Committee of the NCHS revised and approved the protocol, ensuring all participants provided their written informed consent. This study is adhered to the Strengthening the Reporting of Observational studies in Epidemiology (STROBE) guideline 58 . 5.2 The definition of masticatory functions Masticatory function was assessed using functional tooth units (FTUs), defined as pairs of opposing teeth (natural or artificial) in the posterior region, excluding third molars. Each premolar pair was assigned a score of 1, and each molar pair a score of 2, yielding a total FTU score ranging from 1 to 12 59 . Masticatory dysfunction was defined as an FTU score of fewer than 5. For subgroup analyses, participants were categorized into four FTU groups: 0–3, 4–6, 7–9, and 10–12. In addition, the number of remaining teeth and complete dentition (28 teeth, excluding third molars) were also recorded and used as exposure variables. 5.3 The diagnosis of Parkinson’s disease (PD) PD cases were identified based on self-reported use of one or more PD medications in the NHANES database, including carbidopa, levodopa, methyldopa, benztropine, ropinirole, entacapone, and amantadine. Individuals with no reported PD medication use were considered not to have PD 60 . 5.4 The inclusion of covariates Related confounders were adjusted to assess the association between masticatory function and PD. Covariates inclusion was aligned with previous studies 20 , 61 . This study included confounders such as age, sex, race/ethnicity (Mexican American, non-Hispanic White, non-Hispanic Black, other Hispanic and Multi-Racial), education level (High school, college or above, or low high school), marital status (with partner or separation/alone), and poverty income ratio (PIR) (< 1.5, 1.5–3.5, ≥ 3.5), and smoking status (never, former, or current), alcohol consumption (Never, former, mild, moderate, or heavy), and obese status measured by the body mass index (BMI) (< 25, 25–30, ≥ 30). Moreover, hypertension, diabetic mellitus (DM), cardiovascular disease (CVD determined by one or more self-reported coronary heart disease, heart attack, chronic heart failure, angina and stroke), chronic kidney disease (CKD) and hyperlipidemia were also included. Continuous variables included systemic inflammation index (SII), healthy eating index (HEI-score) and the number of remaining teeth. 5.5 Statistical analyses This study included two step analyses with the primary was only included the basic covariates and the secondary included the covariates of CKD, hyperlipidemia, SII and HEI-score. According to the NHANES sampling design, the 20-year composite weights was re-calculated in the two step analyses with the primary used the “WTMEC2YR” and the secondary used “WTDRD1”. In the primary analyses, the baseline characteristics of included participants were stratified into two groups based on the DR status. Continuous variables were expressed as weighted mean ± standard deviation (SD), whereas categorical variables as proportion (%) and counts (n). The comparisons between groups used the Weighted Student’s t-tests and weighted Chi-square tests. Multivariate logistic models were used to calculate the odds ratio (OR) and confidence interval (CI) to assess the impact of FTU and masticatory parameters on DR across three models: Model I (No adjustment), Model II (Adjustment for age, sex, race, poverty, marital status and education level) and Model III (Adjustment for age, sex, race, poverty, marital status, education level, BMI, smoke, alcohol consumption, diabetes, hypertension, CVD). The secondary analyses were conducted using multivariate logistic regression based on Model III, which included additional adjustments for CKD, hyperlipidemia, SII, and HEI score. Restricted cubic spline (RCS) analyses were conducted to determine the presence non-linear relationship between FTU and PD. Subgroup analyses were also performed to examine the stability of the association between FTU and PD across different groups. All analyses accounted for the survey design and weight using R (version 4.3.3). A P -value less than 0.05 was considered statistically significant. Declarations Ethics approval and consent to participate The studies involving human participants were approved by the Ethics Review Board of the National Center for Health Statistics. They were conducted in accordance with local regulations and institutional guidelines. All participants provided their written informed consent. Consent for publication Not applicable. Declaration of competing interest The authors have no conflicts of interest to disclose. Funding This study did not receive any funding or financial support. All work for this article was fully self-funded by the authors, and no acknowledgments are necessary. Author Contribution Ziyang Zheng: Conceptualization, Methodology, Writing–review & editing, Data curation, Formal analysis; Jiaqi Wu: Conceptualization, Investigation, Software, Writing-original draft. Acknowledgement The authors appreciate the NHANES open policy and the provided data as well as all participants and staffs in this study. Data Availability The findings of this study are supported by data from the NHANES (National Health and Nutrition Examination Survey). The dataset is publicly available and can be accessed directly at the following link: [https://wwwn.cdc.gov/nchs/nhanes/](https:/wwwn.cdc.gov/nchs/nhanes) . References Hayes MT. Parkinson’s disease and parkinsonism. Am J Med . 2019;132(7):802–807. doi: 10.1016/j.amjmed.2019.03.001 Tanner CM, Ostrem JL. Parkinson’s disease. Ropper AH, ed. N Engl J Med . 2024;391(5):442–452. doi: 10.1056/NEJMra2401857 Zhu J, Cui Y, Zhang J, et al. Temporal trends in the prevalence of Parkinson’s disease from 1980 to 2023: a systematic review and meta-analysis. Lancet Healthy Longev . 2024;5(7):e464-e479. doi: 10.1016/S2666-7568(24)00094-1 Pereira GM, Teixeira-Dos-Santos D, Soares NM, et al. 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Serum albumin, cognitive function, motor impairment, and survival prognosis in parkinson disease. Medicine (Baltimore) . 2022;101(37):e30324. doi: 10.1097/MD.0000000000030324 Collins LM, Toulouse A, Connor TJ, Nolan YM. Contributions of central and systemic inflammation to the pathophysiology of Parkinson’s disease. Neuropharmacology . 2012;62(7):2154–2168. doi: 10.1016/j.neuropharm.2012.01.028 Qu Y, Li J, Qin Q, et al. A systematic review and meta-analysis of inflammatory biomarkers in parkinson’s disease. npj Parkinson’s Dis . 2023;9(1):18. doi: 10.1038/s41531-023-00449-5 Furutama D, Matsuda S, Yamawaki Y, et al. IL-6 induced by periodontal inflammation causes neuroinflammation and disrupts the blood-brain barrier. Brain Sci . 2020;10(10):679. doi: 10.3390/brainsci10100679 Jiang Y, Xu L, Zhao X, et al. Porphyromonas gingivalis-induced periodontitis promotes neuroinflammation and neuronal loss associated with dysfunction of the brain barrier. 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Parkinsons Dis . 2021;2021:5571556. doi: 10.1155/2021/5571556 Rozas NS, Tribble GD, Jeter CB. Oral Factors That Impact the Oral Microbiota in Parkinson’s Disease. Microorganisms . 2021;9(8):1616. doi: 10.3390/microorganisms9081616 Rozas NS, Sadowsky JM, Jones DJ, Jeter CB. Incorporating oral health into interprofessional care teams for patients with parkinson’s disease. Park Relat Disord . 2017;43:9–14. Accessed August 18, 2025. https://www.sciencedirect.com/science/article/pii/S1353802017302596 von Elm E, Altman DG, Egger M, et al. The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement: guidelines for reporting observational studies. Lancet (lond Engl) . 2007;370(9596):1453–1457. doi: 10.1016/S0140-6736(07)61602-X Ueno M, Yanagisawa T, Shinada K, Ohara S, Kawaguchi Y. Masticatory ability and functional tooth units in Japanese adults. J Oral Rehabil . 2008;35(5):337–344. doi: 10.1111/j.1365-2842.2008.01847.x Lyra P, Botelho J, Machado V, et al. Self-reported periodontitis and C-reactive protein in parkinson’s disease: a cross-sectional study of two american cohorts. npj Parkinson’s Dis . 2022;8(1):40. doi: 10.1038/s41531-022-00302-1 Zhou X, Zhao J, Liu Y, et al. Association between serum potassium and parkinson’s disease in the US (NHANES 2005–2020). Front Neurosci . 2024;18:1387266. Accessed August 20, 2025. https://www.frontiersin.org/articles/ 10.3389/fnins.2024.1387266/full Additional Declarations No competing interests reported. Supplementary Files Supplementarytables.docx Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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11:53:58","extension":"html","order_by":9,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":188256,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-7634776/v1/7a715aabd97ecce1b6600c3b.html"},{"id":94760066,"identity":"68dca3c5-a75f-433b-9f26-da68a2a7ff93","added_by":"auto","created_at":"2025-10-30 11:54:03","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":419813,"visible":true,"origin":"","legend":"\u003cp\u003eThe flowchart of this study.\u003c/p\u003e\n\u003cp\u003eAbbreviations: FTU: functional teeth unit; PD: Parkinson’s disease.\u003c/p\u003e","description":"","filename":"Onlinefloatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-7634776/v1/1e3e6ae86964d62e7d5b7130.png"},{"id":94760043,"identity":"bfcbc75c-6753-4dfc-81d1-d0c18c00e307","added_by":"auto","created_at":"2025-10-30 11:53:57","extension":"jpeg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":189589,"visible":true,"origin":"","legend":"\u003cp\u003eRCS plot of relationship between FTU and PD.\u003c/p\u003e\n\u003cp\u003eAbbreviations: FTU: functional teeth unit; PD: Parkinson’s disease.\u003c/p\u003e","description":"","filename":"floatimage2.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7634776/v1/06ac02a27afa1a3e42e1e523.jpeg"},{"id":96452762,"identity":"5e521d4b-2d2f-46f0-a5b2-bf1ee4aaeccf","added_by":"auto","created_at":"2025-11-21 09:43:03","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1436980,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7634776/v1/c1ff7bc0-f5a3-4e88-8b47-bf81d0b3690e.pdf"},{"id":94760028,"identity":"26d9b57b-624d-49d0-898d-a5874b9a03e7","added_by":"auto","created_at":"2025-10-30 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Introduction","content":"\u003cp\u003eCharacterized by degeneration of the substantia nigra pars compacta and by accumulation of α-synuclein in Lewy bodies, Parkinson\u0026rsquo;s disease (PD), is the second common but complex progressive neurodegenerative disease \u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u003c/sup\u003e. Motor symptoms include tremor and bradykinesia, and nonmotor motor impairments include disorder of mood, sleep, sensation, cognition and autonomic function, both of which are preceding the motor signs\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e. The global prevalence of PD is in growth with 1.51 cases per 1000, and those countries with high sociodemographic levels were prominent\u003csup\u003e\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u003c/sup\u003e, and those in lower to upper-middle-income countries were more pronounced\u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e. The age-standardized disability-adjusted life-year was observed largest in PD\u003csup\u003e5\u003c/sup\u003e. In 2050, the prevalence was projected to at 267 per 100 000, and aging was projected to be the primary contributor\u003csup\u003e\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eRisk factors for PD include positive association with the history of anxiety or depression, pesticide exposure, head injury, rural living, β blockers, farming occupation, and well-water drinking while negative with coffee drinking, hypertension, nonsteroidal anti-inflammatory drugs, calcium channel blockers, and alcohol\u003csup\u003e\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u003c/sup\u003e. Patients with PD commonly experienced chewing difficulties, denture discomfort, loss of natural teeth, poor oral hygiene, and swallowing problems\u003csup\u003e\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u003c/sup\u003e. The self-assessed oral health-related quality of life (OHRQoL) was impaired by the oral symptoms including xerostomia, drooling and dysphagia in those with PD, however, they reported adequate dental health care\u003csup\u003e\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u003c/sup\u003e. Moreover, motor aspects of experiences of daily living of PD related variable were correlated with the OHRQoL, and oral health related variables were also related including the oral environment ailment during disease course, being dentate, tooth wear and burning mouth syndrome\u003csup\u003e\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u003c/sup\u003e. Then, PD may be a possible factor in periodontal health breakdown\u003csup\u003e\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u003c/sup\u003e. The masticatory and orofacial function are impaired in those with moderate to advanced PD, and these problems become marked with the progression of PD\u003csup\u003e12\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eNoted, PD was associated with impaired masticatory function, specifically the range of jaw motion, longer duration, slower velocity of masticatory cycle and lower maximum bite force\u003csup\u003e\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u003c/sup\u003e. Conversely, oral health is associated with PD. Patients with temporomandibular disorder was in higher risk of PD development, and vice versa\u003csup\u003e\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u003c/sup\u003e. Those with exposure to dental amalgam fillings were more susceptible to PD compared to those non-exposed\u003csup\u003e\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e\u003c/sup\u003e. Then, paining gums is correlated with increased susceptibility of PD based on UK biobank\u003csup\u003e\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u003c/sup\u003e. Periodontal inflammatory disease (PID) was also associated with PD development\u003csup\u003e\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e\u003c/sup\u003e. Moreover, the number of tooth loss was positively associated with higher risk of new-onset PD development\u003csup\u003e\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eInfluenced by the periodontal status, tooth counts and functional teeth, masticatory function is closely correlated with general health conditions\u003csup\u003e\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u003c/sup\u003e. Considering that masticatory ability is associated with cognition\u003csup\u003e\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e\u003c/sup\u003e and depression\u003csup\u003e\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u003c/sup\u003e, both of which are risk for the PD. With the expanding economic and health burden of neurodegenerative diseases, the multidisciplinary approaches for addressing risk factors verifications and the unmet medical and social need is urgent needed\u003csup\u003e\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e\u003c/sup\u003e. There may be an association between masticatory performance with PD. As this area remains insufficiently explored, further study into the association between masticatory function and the risk of PD in a nationally representative sample is warranted.\u003c/p\u003e\u003cp\u003eHence, this aim of this study examines the association between masticatory function and the risk of PD using data from the NHANES, offering new insights to oral alterations of alert or progression of PD and preservation of ideal mastication for the prevention and management of individuals with PD.\u003c/p\u003e"},{"header":"2. Results","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003e2.1 Basic characteristics of study population\u003c/h2\u003e\u003cp\u003eThe flow chart of participants inclusion is illustrated in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. In the primary analysis, 37,668 participants were included, among whom 334 were diagnosed with PD, yielding a weighted prevalence of 0.8%. After adjusting for additional covariates, the secondary analysis comprised 34,941 participants, of whom 312 were diagnosed with PD, corresponding to a prevalence of 0.83%. Baseline characteristics of participants is presented in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e according to PD status and the baseline by FTU subgroups is presented in Table \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e. The mean FTU values were 5.70 for individuals with PD and 8.31 for those without PD, while the mean number of teeth was 19.09 and 23.13, respectively. Both differences were statistically significant. The baseline of the secondary analysis is presented in Table S2.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eBaseline characteristics according to the presence of PD in the primary analyses.\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"5\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eVariable\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eTotal\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eNon-PD\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003ePD\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e-value\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAge (year)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e47.33(0.21)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e47.25(0.21)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e56.87(1.06)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eTooth number\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e23.10(0.11)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e23.13(0.11)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e19.09(0.75)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFTU\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e8.29(0.06)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e8.31(0.06)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e5.70(0.35)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGender\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.01\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFemale\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e18559(50.49)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e18387(50.42)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e172(59.35)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMale\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e19109(49.51)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e18947(49.58)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e162(40.65)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eRace\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.03\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMexican American\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e6228(7.48)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e6189(7.50)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e39(4.28)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNon-Hispanic Black\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e7738(10.34)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e7686(10.35)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e52(8.72)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNon-Hispanic White\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e17605(70.88)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e17400(70.81)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e205(79.28)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eOther Hispanic\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e2893(5.11)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e2869(5.13)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e24(3.58)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eOther Race\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e3204(6.19)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e3190(6.21)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e14(4.14)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eEducation level\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.21\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBelow high school\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e9473(15.87)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e9370(15.83)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e103(20.17)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eHigh school\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e8733(23.92)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e8663(23.91)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e70(24.92)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAbove high school\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e19462(60.21)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e19301(60.26)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e161(54.91)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePoverty\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eLow income\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e11062(20.11)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e10940(20.05)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e122(27.99)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eModerate income\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e14422(35.71)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e14293(35.68)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e129(39.75)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eHigh income\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e12184(44.17)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e12101(44.27)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e83(32.26)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMarital status\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.01\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMarried/Living with Partner\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e22873(64.53)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e22691(64.57)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e182(59.97)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eWidowed/Divorced/Separated\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e8502(18.62)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e8402(18.55)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e100(27.15)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNever married\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e6293(16.84)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e6241(16.88)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e52(12.88)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBody mass index\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.18\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e11053(30.86)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e10965(30.87)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e88(28.84)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eOverweight\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e12795(33.37)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e12700(33.41)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e95(28.65)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eObese\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e13820(35.78)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e13669(35.72)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e151(42.51)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSmoke\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.32\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNever\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e20036(53.34)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e19877(53.34)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e159(52.70)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFormer\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e9645(25.35)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e9552(25.37)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e93(22.32)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNow\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e7987(21.32)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e7905(21.29)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e82(24.98)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAlcohol consumption\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNever\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e5212(10.93)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e5165(10.92)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e47(13.02)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFormer\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e6639(14.37)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e6539(14.29)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e100(24.90)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMild\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e12795(36.52)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e12678(36.52)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e117(37.19)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eModerate\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e5640(17.22)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e5615(17.29)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e25(9.31)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eHeavy\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e7382(20.95)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e7337(20.99)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e45(15.58)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDiabetes\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNo\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e31841(88.79)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e31594(88.86)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e247(80.43)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eYes\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e5827(11.21)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e5740(11.14)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e87(19.57)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eHypertension\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNo\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e21432(62.47)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e21291(62.60)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e141(46.53)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eYes\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e16236(37.53)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e16043(37.40)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e193(53.47)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCVD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNo\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e33475(91.40)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e33228(91.50)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e247(79.60)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eYes\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e4193(8.60)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e4106(8.50)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e87(20.40)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFunctional dentition\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNo\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e9455(17.70)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e9318(17.56)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e137(34.79)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eYes\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e28213(82.30)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e28016(82.44)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e197(65.21)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMasticatory dysfunction\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNo\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e25655(76.75)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e25497(76.94)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e158(53.95)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eYes\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e12013(23.25)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e11837(23.06)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e176(46.05)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eComplete dentition\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNo\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e25783(60.65)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e25494(60.48)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e289(82.05)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eYes\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e11885(39.35)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e11840(39.52)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e45(17.95)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e\u003ch2\u003e2.2 Associations between masticatory functions with PD\u003c/h2\u003e\u003cp\u003eThe correlation between FTU and PD is detailed in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. In the fully adjusted model, each one-unit increase in FTU was associated with a 7.7% lower prevalence of PD (OR\u0026thinsp;=\u0026thinsp;0.923, 95% CI 0.879\u0026ndash;0.969, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.002), and those having an FTU score of 10\u0026ndash;12 was associated with a 48.2% lower prevalence of PD (OR\u0026thinsp;=\u0026thinsp;0.518, 95% CI 0.298\u0026ndash;0.901, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.020). Higher FTU values were associated with a reduced risk of PD (\u003cem\u003eP\u003c/em\u003e for trend\u0026thinsp;\u0026lt;\u0026thinsp;0.05). As shown in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e, molar FTU (OR\u0026thinsp;=\u0026thinsp;0.884, 95% CI 0.825\u0026ndash;0.948, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001) and tooth counts (OR\u0026thinsp;=\u0026thinsp;0.978, 95% CI 0.956-1.000, P\u0026thinsp;=\u0026thinsp;0.048) were associated with a lower risk of PD, whereas masticatory dysfunction (OR\u0026thinsp;=\u0026thinsp;1.820, 95% CI 1.172\u0026ndash;2.826, P\u0026thinsp;=\u0026thinsp;0.008) and incomplete dentition (OR\u0026thinsp;=\u0026thinsp;2.017, 95% CI 1.312\u0026ndash;3.101, P\u0026thinsp;=\u0026thinsp;0.002) were linked to an increased risk of PD. However, no significant associations were found between premolar FTU and functional dentition with PD.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eAssociation between FTU and PD in the primary analyses.\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"8\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eVariables\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eModel I\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eModel II\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003eModel III\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eContinuous\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eFTU\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eOR[CI]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eOR[CI]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003eOR[CI]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.889(0.864,0.915)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;.001\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.916(0.877,0.957)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;.001\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.923(0.879,0.969)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e\u003cb\u003e0.002\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCategorical\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e0\u0026ndash;3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eReference\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e4\u0026ndash;6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1.161(0.796,1.693)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.435\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1.320(0.887,1.965)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.169\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e1.384(0.930,2.060)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.108\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e7\u0026ndash;9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.380(0.238,0.608)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;.001\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.470(0.286,0.772)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003e0.003\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.511(0.305,0.856)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e\u003cb\u003e0.011\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e10\u0026ndash;12\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.320(0.227,0.452)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;.001\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.472(0.285,0.782)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003e0.004\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.518(0.298,0.901)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e\u003cb\u003e0.020\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e for trend\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;.001\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;.001\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e\u003cb\u003e0.004\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"8\"\u003eAbbreviations: FTU: functional teeth unit; PD: Parkinson\u0026rsquo;s disease.\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd colspan=\"8\"\u003eWeighted multivariable logistic regression analyses were performed with FTU as the main independent variable. Odds ratios (ORs) were calculated to evaluate the association between FTU and PD across Model I (no adjustment), Model II (adjustments of age, race/ethnicity, sex, poverty level, education, and marital status), and Model III (fully adjustments of all covariates).\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eAssociation between masticatory parameters and PD in the primary analyses.\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"7\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eVariables\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eModel I\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eModel II\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eModel III\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eOR[CI]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eOR[CI]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003eOR[CI]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePremolar FTU\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.764(0.706,0.828)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;.001\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.866(0.774,0.967)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003e0.011\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.892(0.794,1.002)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.054\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMolar FTU\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.845(0.809,0.882)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;.001\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.877(0.824,0.933)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;.001\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.884(0.825,0.948)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;.001\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eTooth counts\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.953(0.941,0.966)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;.001\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.972(0.952,0.993)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003e0.009\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.978(0.956,1.000)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e\u003cb\u003e0.048\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMasticatory dysfunction\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2.847(2.120,3.824)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;.001\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.985(1.334,2.954)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;.001\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e1.820(1.172,2.826)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e\u003cb\u003e0.008\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFunctional dentition\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.399(0.297,0.536)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;.001\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.623(0.418,0.931)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003e0.021\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.692(0.453,1.057)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.088\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eComplete dentition\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2.987(2.069,4.311)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;.001\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2.128(1.407,3.218)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;.001\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e2.017(1.312,3.101)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e\u003cb\u003e0.002\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"7\"\u003eAbbreviations: FTU: functional teeth unit; PD: Parkinson\u0026rsquo;s disease.\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd colspan=\"7\"\u003eWeighted multivariable logistic regression analyses were performed with masticatory parameters as the main independent variable. Odds ratios (ORs) were calculated to evaluate the association between masticatory parameters and PD across Model I (no adjustment), Model II (adjustments of age, race/ethnicity, sex, poverty level, education, and marital status), and Model III (fully adjustments of all covariates).\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec5\" class=\"Section2\"\u003e\u003ch2\u003e2.3 Sensitivity analyses\u003c/h2\u003e\u003cp\u003eSensitivity analyses were conducted in the secondary analysis by further adjustments of CKD, hyperlipidemia, SII, and HEI score (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). FTU (OR\u0026thinsp;=\u0026thinsp;0.928, 95% CI 0.875\u0026ndash;0.985, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.015) was associated with lower risk of DR, while masticatory dysfunction (OR\u0026thinsp;=\u0026thinsp;1.759, 95% CI 1.046\u0026ndash;2.957, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.033) and incomplete dentition (OR\u0026thinsp;=\u0026thinsp;2.121, 95% CI 1.311\u0026ndash;3.431, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.002) were with an increased risk of DR. FTU score of 10\u0026ndash;12 was slightly associated with the risk of PD (OR\u0026thinsp;=\u0026thinsp;0.509, 95% CI 0.259\u0026ndash;1.003, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.051). These results further reinforced the robustness of the relationship between mastication and PD.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eSensitivity analyses (Association between masticatory function and PD in the second analyses).\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"5\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colspan=\"3\" nameend=\"c5\" namest=\"c3\"\u003e\u003cp\u003e0\u0026ndash;3/ Reference\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eVariables\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eFTU\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e4\u0026ndash;6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e7\u0026ndash;9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e10\u0026ndash;12\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eOR[CI]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.928(0.875,0.985)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.958(0.583,1.572)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.594(0.302,1.170)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.509(0.259,1.003)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e0.015\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.863\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.131\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.051\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eVariables\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eTooth counts\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eMasticatory dysfunction\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eFunctional dentition\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eComplete dentition\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eOR[CI]\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.979(0.951,1.008)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1.759(1.046,2.957)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.686(0.410,1.146)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e2.121(1.311,3.431)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.151\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e0.033\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.149\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cb\u003e0.002\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"5\"\u003eAbbreviations: FTU: functional teeth unit; PD: Parkinson\u0026rsquo;s disease.\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd colspan=\"5\"\u003eWeighted multivariable logistic regression analyses were performed with masticatory functions as the main independent variable. Odds ratios (ORs) were calculated to evaluate the association between masticatory functions and PD across Model I (no adjustment), Model II (adjustments of age, race/ethnicity, sex, poverty level, education, and marital status), and Model III (fully adjustments of all covariates).\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec6\" class=\"Section2\"\u003e\u003ch2\u003e2.4 RCS and stratified analyses\u003c/h2\u003e\u003cp\u003eNon-linear relationship was detected by RCS analyses. In the relationship between FTU and PD (Figs.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e), a linear relationship between FTU and DR was found (\u003cem\u003eP\u003c/em\u003e for nonlinearity\u0026thinsp;=\u0026thinsp;0.0661). Stratified analyses were conducted to assess the stability of the relationship between FTU and PD across different subgroups (Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e). The results indicated that this relationship remained stable in all subgroups except for age, DM, and hypertension (P for interaction\u0026thinsp;\u0026lt;\u0026thinsp;0.05). Specifically, the association was consistent in individuals aged over 60 (OR\u0026thinsp;=\u0026thinsp;0.934, 95% CI 0.888\u0026ndash;0.981), those without DM (OR\u0026thinsp;=\u0026thinsp;0.916, 95% CI 0.868\u0026ndash;0.967), and those without hypertension (OR\u0026thinsp;=\u0026thinsp;0.858, 95% CI 0.798\u0026ndash;0.922).\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab5\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eStratified analyses of FTU on PD.\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"4\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCharacter\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003e95% CI\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e for interaction\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAge\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003e0.015\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e30\u0026ndash;45\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.870(0.783, 0.967)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e0.010\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e45\u0026ndash;60\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.962(0.889, 1.042)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.339\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u0026gt;\u0026thinsp;60\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.934(0.888,0.981)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e0.007\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGender\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.395\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMale\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.949(0.894,1.007)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.084\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFemale\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.912(0.854,0.975)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e0.007\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eEducation level\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.314\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBelow high school\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.975(0.907,1.049)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.496\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eHigh school\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.899(0.808, 1.001)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.052\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAbove high school\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.921(0.869,0.976)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e0.006\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePoverty\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.62\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eLow income\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.935(0.862,1.015)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.109\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eModerate income\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.909(0.848,0.975)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e0.008\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eHigh income\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.942(0.860, 1.031)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.191\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBody mass index\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.905\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.954(0.876, 1.038)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.269\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eOverweight\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.892(0.818,0.973)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e0.010\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eObese\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.936(0.876,1.001)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.052\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSmoke\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.248\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNever\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.951(0.890,1.016)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.133\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFormer\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.822(0.742,0.910)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;.001\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNow\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.954(0.876,1.038)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.272\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAlcohol consumption\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.202\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNever\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.942(0.829, 1.069)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.351\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFormer\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.990(0.926, 1.057)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.757\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMild\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.903(0.837,0.974)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e0.009\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eModerate\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.775(0.665, 0.902)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e0.001\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eHeavy\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.960(0.859,1.074)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.476\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDM\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003e0.013\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNo\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.916(0.868,0.967)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e0.002\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eYes\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.975(0.906,1.049)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.498\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eHypertension\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;.001\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNo\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.858(0.798,0.922)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;.001\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eYes\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.991(0.941,1.044)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.736\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCVD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.105\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNo\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.929(0.883,0.977)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e0.005\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eYes\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.945(0.863,1.035)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.223\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"4\"\u003eAbbreviations: CVD: cardiovascular diseases; FTU: functional teeth unit; PD: Parkinson\u0026rsquo;s disease.\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e"},{"header":"3. Discussion","content":"\u003cp\u003eIn the present study, the relationship between masticatory function and the risk of PD was unveiled. These findings suggest that the maintenance of masticatory function is beneficial to PD prevalence and progression. Poor mastication may be an alert of PD incidence and progression, and good oral hygiene, routine oral healthcare and the restoration of missing teeth and caries may be preventable for PD incidence and progression.\u003c/p\u003e\u003cp\u003eThis study aligns with previous research, indicating that oral health may influence both the prevalence and severity of PD. Regarding the effects of PD on oral health, PD patients showed less interdental hygiene, higher plaque index, higher risk of drooling, hyposialia, dysphagia and chewing difficulty\u003csup\u003e\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e\u003c/sup\u003e. All evaluated periodontal parameters deteriorated with the severity of PD, the prevalence of periodontal description was high even in the early stages of PD\u003csup\u003e24\u003c/sup\u003e. Then, the frequency of untreated dental caries and tooth loss was significantly higher than those without PD\u003csup\u003e25\u003c/sup\u003e. Also, patients with PD complained about xerostomia, which was underestimated by themselves compared with healthy\u003csup\u003e\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e\u003c/sup\u003e. PD patients had poor oral health status and decreased oral health care, the PD duration and severity were correlated with chewing problems\u003csup\u003e\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e\u003c/sup\u003e. Advanced PD stage was associated with poor periodontal health, and motor impairment was associated with increased number of untreated caries, poor oral hygiene and periodontal status, difficulties of chewing and swallowing were common in those with more decayed teeth\u003csup\u003e\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e\u003c/sup\u003e. However, these conditions of poor oral health are mostly preventable\u003csup\u003e\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eRegarding the masticatory dysfunction of PD patients. The progression of motor dysfunction in patients with PD had an effect on the chewing speed, which may be correlated with the nutritional decline\u003csup\u003e\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e\u003c/sup\u003e. PD patients had objective and subjective poor orofacial function including limitation of jaw mobility and function and mastication\u003csup\u003e\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e\u003c/sup\u003e. Those with PD had impaired masticatory function during the levodopa on-period and the mastication was worse in off-period\u003csup\u003e\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e,\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eAfter odontological treatment, the jaw opening, chewing time and hygiene were significantly improved in those PD participants, suggesting that simple measures like dental hygiene instruction, training of jaw opening, lip and chewing exercise could delay the PD progression\u003csup\u003e\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e\u003c/sup\u003e. Standardized exercise of jaw and orofacial muscles with individualized oral hygiene programme also resulted in improved orofacial function and OHRQoL\u003csup\u003e\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e\u003c/sup\u003e. Then, in those with PD stage 2 to 4 without prandial dysphagia, gum chewing may increase swallow frequency and decrease latency of swallowing\u003csup\u003e\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e\u003c/sup\u003e. Moreover, after the insertion of removable prostheses, the masticatory efficiency (ME) of PD patients was improved, though the was similar but the ME in PD was less than the control\u003csup\u003e\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eThen, there was a weak association between periodontitis and PD from the National Health Insurance Service of South Korea, this relationship was prominent when PD combining with metabolic syndrome\u003csup\u003e\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e\u003c/sup\u003e. Individuals without PID who underwent the dental scaling over five consecutive years had a lower risk of developing PD\u003csup\u003e38\u003c/sup\u003e. These evidence were aligned with the findings that tooth loss was a predictor of new-onset PD\u003csup\u003e18\u003c/sup\u003e when considering that periodontal status and tooth counts are closely correlated with mastication.\u003c/p\u003e\u003cp\u003eMechanisms under in the association between masticatory function and PD remained unclear, but the potential hypotheses may be accounted by nutritional status, orofacial function, neuroinflammation and oral microbiome\u003csup\u003e\u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eFirst, masticatory function is closely related with food and nutrient intake, leading to decrease of diet quantity and quality, subsequently to the undernutrition\u003csup\u003e\u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e40\u003c/span\u003e\u003c/sup\u003e. Mastication measured is correlated with nutritional status\u003csup\u003e\u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e\u003c/sup\u003e including plasma albumin levels, BMI in the females\u003csup\u003e\u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e42\u003c/span\u003e\u003c/sup\u003e and calf circumference in the elderly\u003csup\u003e\u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e43\u003c/span\u003e\u003c/sup\u003e. Meantime, the prevalence of malnutrition and nutritional disorders were 8.89% and 42.3%\u003csup\u003e44\u003c/sup\u003e. Serum albumin was decreased in those with PD and could be an independent risk factor for PD\u003csup\u003e45\u003c/sup\u003e. Then, it was associated with lower risk of severe motor impairment and PD-related death in those with PD\u003csup\u003e46\u003c/sup\u003e. Mastication may correlate with PD by the nutritional status, and this may be attributed to serum albumin levels.\u003c/p\u003e\u003cp\u003eThen, continuous local and systemic inflammation is consistently associated with the pathophysiology of PD\u003csup\u003e47\u003c/sup\u003e. PD patients exhibited significant alterations of peripheral and cerebrospinal fluid inflammatory biomarkers\u003csup\u003e\u003cspan citationid=\"CR48\" class=\"CitationRef\"\u003e48\u003c/span\u003e\u003c/sup\u003e. Periodontitis is characterized by systemic inflammation, which could induce the neuroinflammation through the disruption of blood-brain barrier\u003csup\u003e\u003cspan citationid=\"CR49\" class=\"CitationRef\"\u003e49\u003c/span\u003e\u003c/sup\u003e, thus inhibiting the clearance of pathogenic substances and enhancing immune cell infiltration in periodontitis mice\u003csup\u003e\u003cspan citationid=\"CR50\" class=\"CitationRef\"\u003e50\u003c/span\u003e\u003c/sup\u003e. Then, by gentle mastication, the diseased periodontium could release bacterial pro-inflammatory biomarkers into bloodstream, which was correlated with the periodontitis severity\u003csup\u003e\u003cspan citationid=\"CR51\" class=\"CitationRef\"\u003e51\u003c/span\u003e\u003c/sup\u003e. Hence, periodontal status may be linked to Parkinson's disease (PD) through systemic inflammation induced by periodontal pathogens, while masticatory function could exacerbate neuroinflammation.\u003c/p\u003e\u003cp\u003eLastly, oral microbiome may play a vital role in the PD pathology. In patients with PD, higher abundance of pathogenic oral bacteria were found, revealing that oral dysbiosis is implicated in the onset and progression of PD\u003csup\u003e52\u003c/sup\u003e. PD may modify the subgingival microbiome and local inflammation expression\u003csup\u003e\u003cspan citationid=\"CR53\" class=\"CitationRef\"\u003e53\u003c/span\u003e,\u003cspan citationid=\"CR54\" class=\"CitationRef\"\u003e54\u003c/span\u003e\u003c/sup\u003e. Then, the dysphagia measured by swallowing disturbance questionnaire (SDQ) was negatively correlated with the oral bacterial counts (OBC) while positive with the disease duration and PD scale, those with lower SDQ showed higher OBC, and OBC was correlated with levodopa daily dose\u003csup\u003e\u003cspan citationid=\"CR55\" class=\"CitationRef\"\u003e55\u003c/span\u003e\u003c/sup\u003e. Patients with PD exhibited significant different soft tissue β diversity to the controls, which may be partially attributed to dysphagia, drooling, and salivary pH, and the abundance of opportunistic pathogens were detected\u003csup\u003e\u003cspan citationid=\"CR56\" class=\"CitationRef\"\u003e56\u003c/span\u003e\u003c/sup\u003e. Hence, oral microbiome dysbiosis plays an integral role in PD pathology.\u003c/p\u003e\u003cp\u003eThis is the first study that investigates the relationship between FTU and PD in a large nationally representative sample. Then, several sensitivity analyses and PSM further substantiate the findings. Moreover, mastication measurements by using FTU are easy and quick. Despite the strengths, several limitations should be acknowledged. First, the cross-sectional design precludes the ability to establish a causal relationship between FTU and PD due to the poor oral health may be after the PD. Second, although potential confounders were relatively comprehensively adjusted for, unmeasured factors effects on these relationships could not be completely ruled out. Third, PD was identified based on self-reported medication questionnaires, which may introduce recall bias. Additionally, FTU was measured solely by the presence of teeth rather than occlusion. The diagnosis of PD should consider both clinical symptoms and disease severity, and an objective assessment of masticatory function requires further quantification.\u003c/p\u003e\u003cp\u003eThis study addresses this gap of mastication function measured by FTU and its effect on PD, encouraging more standardized and innovative methods to re-examine the relationship of mastication and multiple neurodegenerative disorders. Future integration of dental professionals, included preventive oral health plans, oral hygiene education and oral emergency reaction, could improve the QoL and delay the progression of PD\u003csup\u003e57\u003c/sup\u003e. Moreover, studies involving diverse regional populations, with prospective designs, large sample sizes, and a focus on the mechanisms linking oral health and PD, are essential to validate the relationship and postulated hypotheses between FTU and PD in this study.\u003c/p\u003e"},{"header":"4. Conclusion","content":"\u003cp\u003eThis study demonstrates an inverse association between masticatory function and the risk of PD in a nationally representative US population. The findings underscore the potential of FTU as a practical tool for the prevention and management assessment of PD, with possible applicability to other neurodegenerative diseases. These results suggest that preserving masticatory function may benefit neurological health.\u003c/p\u003e"},{"header":"5. Methods","content":"\u003cdiv id=\"Sec10\" class=\"Section2\"\u003e\u003ch2\u003e5.1 Study population and design\u003c/h2\u003e\u003cp\u003eConducted by the National Center for Health Statistics (NCHS) of the Centers for Disease Control and Prevention (CDC), NHANES is an ongoing multistage program that evaluates the general health and nutritional status of participants in the United States. The Ethics Review Committee of the NCHS revised and approved the protocol, ensuring all participants provided their written informed consent. This study is adhered to the Strengthening the Reporting of Observational studies in Epidemiology (STROBE) guideline\u003csup\u003e\u003cspan citationid=\"CR58\" class=\"CitationRef\"\u003e58\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\u003ch2\u003e5.2 The definition of masticatory functions\u003c/h2\u003e\u003cp\u003eMasticatory function was assessed using functional tooth units (FTUs), defined as pairs of opposing teeth (natural or artificial) in the posterior region, excluding third molars. Each premolar pair was assigned a score of 1, and each molar pair a score of 2, yielding a total FTU score ranging from 1 to 12\u003csup\u003e59\u003c/sup\u003e. Masticatory dysfunction was defined as an FTU score of fewer than 5. For subgroup analyses, participants were categorized into four FTU groups: 0\u0026ndash;3, 4\u0026ndash;6, 7\u0026ndash;9, and 10\u0026ndash;12. In addition, the number of remaining teeth and complete dentition (28 teeth, excluding third molars) were also recorded and used as exposure variables.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\u003ch2\u003e5.3 The diagnosis of Parkinson\u0026rsquo;s disease (PD)\u003c/h2\u003e\u003cp\u003ePD cases were identified based on self-reported use of one or more PD medications in the NHANES database, including carbidopa, levodopa, methyldopa, benztropine, ropinirole, entacapone, and amantadine. Individuals with no reported PD medication use were considered not to have PD\u003csup\u003e60\u003c/sup\u003e.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec13\" class=\"Section2\"\u003e\u003ch2\u003e5.4 The inclusion of covariates\u003c/h2\u003e\u003cp\u003eRelated confounders were adjusted to assess the association between masticatory function and PD. Covariates inclusion was aligned with previous studies\u003csup\u003e\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e,\u003cspan citationid=\"CR61\" class=\"CitationRef\"\u003e61\u003c/span\u003e\u003c/sup\u003e. This study included confounders such as age, sex, race/ethnicity (Mexican American, non-Hispanic White, non-Hispanic Black, other Hispanic and Multi-Racial), education level (High school, college or above, or low high school), marital status (with partner or separation/alone), and poverty income ratio (PIR) (\u0026lt;\u0026thinsp;1.5, 1.5\u0026ndash;3.5, \u0026ge;\u0026thinsp;3.5), and smoking status (never, former, or current), alcohol consumption (Never, former, mild, moderate, or heavy), and obese status measured by the body mass index (BMI) (\u0026lt;\u0026thinsp;25, 25\u0026ndash;30, \u0026ge;\u0026thinsp;30). Moreover, hypertension, diabetic mellitus (DM), cardiovascular disease (CVD determined by one or more self-reported coronary heart disease, heart attack, chronic heart failure, angina and stroke), chronic kidney disease (CKD) and hyperlipidemia were also included. Continuous variables included systemic inflammation index (SII), healthy eating index (HEI-score) and the number of remaining teeth.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec14\" class=\"Section2\"\u003e\u003ch2\u003e5.5 Statistical analyses\u003c/h2\u003e\u003cp\u003eThis study included two step analyses with the primary was only included the basic covariates and the secondary included the covariates of CKD, hyperlipidemia, SII and HEI-score. According to the NHANES sampling design, the 20-year composite weights was re-calculated in the two step analyses with the primary used the \u0026ldquo;WTMEC2YR\u0026rdquo; and the secondary used \u0026ldquo;WTDRD1\u0026rdquo;. In the primary analyses, the baseline characteristics of included participants were stratified into two groups based on the DR status. Continuous variables were expressed as weighted mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation (SD), whereas categorical variables as proportion (%) and counts (n). The comparisons between groups used the Weighted Student\u0026rsquo;s t-tests and weighted Chi-square tests. Multivariate logistic models were used to calculate the odds ratio (OR) and confidence interval (CI) to assess the impact of FTU and masticatory parameters on DR across three models: Model I (No adjustment), Model II (Adjustment for age, sex, race, poverty, marital status and education level) and Model III (Adjustment for age, sex, race, poverty, marital status, education level, BMI, smoke, alcohol consumption, diabetes, hypertension, CVD). The secondary analyses were conducted using multivariate logistic regression based on Model III, which included additional adjustments for CKD, hyperlipidemia, SII, and HEI score. Restricted cubic spline (RCS) analyses were conducted to determine the presence non-linear relationship between FTU and PD. Subgroup analyses were also performed to examine the stability of the association between FTU and PD across different groups. All analyses accounted for the survey design and weight using R (version 4.3.3). A \u003cem\u003eP\u003c/em\u003e-value less than 0.05 was considered statistically significant.\u003c/p\u003e\u003c/div\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003ch2\u003eEthics approval and consent to participate\u003c/h2\u003e\u003cp\u003eThe studies involving human participants were approved by the Ethics Review Board of the National Center for Health Statistics. They were conducted in accordance with local regulations and institutional guidelines. All participants provided their written informed consent.\u003c/p\u003e\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003cp\u003eNot applicable.\u003c/p\u003e\u003c/p\u003e\u003cp\u003e\u003ch2\u003eDeclaration of competing interest\u003c/h2\u003e\u003cp\u003eThe authors have no conflicts of interest to disclose.\u003c/p\u003e\u003c/p\u003e\u003ch2\u003eFunding\u003c/h2\u003e\u003cp\u003eThis study did not receive any funding or financial support. All work for this article was fully self-funded by the authors, and no acknowledgments are necessary.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eZiyang Zheng: Conceptualization, Methodology, Writing\u0026ndash;review \u0026amp; editing, Data curation, Formal analysis; Jiaqi Wu: Conceptualization, Investigation, Software, Writing-original draft.\u003c/p\u003e\u003ch2\u003eAcknowledgement\u003c/h2\u003e\u003cp\u003eThe authors appreciate the NHANES open policy and the provided data as well as all participants and staffs in this study.\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eThe findings of this study are supported by data from the NHANES (National Health and Nutrition Examination Survey). The dataset is publicly available and can be accessed directly at the following link: [https://wwwn.cdc.gov/nchs/nhanes/](https:/wwwn.cdc.gov/nchs/nhanes) .\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eHayes MT. Parkinson\u0026rsquo;s disease and parkinsonism. \u003cem\u003eAm J Med\u003c/em\u003e. 2019;132(7):802\u0026ndash;807. doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.amjmed.2019.03.001\u003c/span\u003e\u003cspan address=\"10.1016/j.amjmed.2019.03.001\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eTanner CM, Ostrem JL. Parkinson\u0026rsquo;s disease. 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Accessed August 20, 2025. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.frontiersin.org/articles/\u003c/span\u003e\u003cspan address=\"https://www.frontiersin.org/articles/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.3389/fnins.2024.1387266/full\u003c/span\u003e\u003cspan address=\"10.3389/fnins.2024.1387266/full\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Masticatory function, functional tooth unit, Parkinson’s disease, NHANES.","lastPublishedDoi":"10.21203/rs.3.rs-7634776/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7634776/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eMasticatory dysfunction may contribute to systemic diseases, including Parkinson\u0026rsquo;s disease (PD), but evidence from large populations is limited. Using data from 37,668 adults in NHANES 1999\u0026ndash;2018, we assessed mastication with functional tooth units (FTUs), and defined PD by medication use. Logistic regression, restricted cubic spline (RCS), and stratified analyses were applied with adjustment for demographic, socioeconomic, lifestyle, and health covariates, and sensitivity analyses were performed. Among participants, 334 had PD (weighted prevalence 0.8%). Mean FTUs (5.70 vs. 8.31) and tooth counts (19.09 vs. 23.13) were significantly lower in PD than non-PD individuals (P\u0026thinsp;\u0026lt;\u0026thinsp;.001). Each unit increase in FTU was associated with reduced PD risk (OR\u0026thinsp;=\u0026thinsp;0.923, 95% CI 0.879\u0026ndash;0.969), and participants with FTU 10\u0026ndash;12 had 48% lower PD prevalence (OR\u0026thinsp;=\u0026thinsp;0.518, 95% CI 0.298\u0026ndash;0.901). Molar FTU and tooth counts were inversely associated with PD, while masticatory dysfunction and incomplete dentition were linked to higher risk. RCS suggested a linear association, with stronger effects observed in older, non-diabetic, and non-hypertensive individuals (P for interaction\u0026thinsp;\u0026lt;\u0026thinsp;0.05). Sensitivity analyses confirmed the robustness of findings. These results indicate that better mastication, reflected by higher FTUs, is associated with reduced PD risk, highlighting the potential role of oral health maintenance in PD prevention and management.\u003c/p\u003e","manuscriptTitle":"Association between masticatory function and Parkinson’s disease: A population-based study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-10-30 11:53:24","doi":"10.21203/rs.3.rs-7634776/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"09cc4113-b285-40d4-a5ad-5da9d8380683","owner":[],"postedDate":"October 30th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":57122586,"name":"Health sciences/Diseases"},{"id":57122587,"name":"Health sciences/Health care"},{"id":57122588,"name":"Health sciences/Medical research"},{"id":57122589,"name":"Health sciences/Neurology"},{"id":57122590,"name":"Health sciences/Risk factors"}],"tags":[],"updatedAt":"2025-11-15T20:38:11+00:00","versionOfRecord":[],"versionCreatedAt":"2025-10-30 11:53:24","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7634776","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7634776","identity":"rs-7634776","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}