Diagnostic accuracy of isometric knee extension strength as a sarcopenia criteria in community-dwelling older women

Diagnostic accuracy of isometric knee extension strength as a sarcopenia criteria in community-dwelling older women | 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 Research Article Diagnostic accuracy of isometric knee extension strength as a sarcopenia criteria in community-dwelling older women Pilar Pérez-Ros, Joaquín Barrachina-Igual, Ana Pablos, Rosa Fonfria-Vivas, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3860792/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 02 Dec, 2024 Read the published version in BMC Geriatrics → Version 1 posted 12 You are reading this latest preprint version Abstract Background. Muscle strength is one of the most reliable measures used for the identification of sarcopenia. The European Working Group on Sarcopenia in Older People update (EWGSOP2) proposed the use of the Grip Strength and Chair Stand tests, while clarifying that isometric torque methods can be used when performing the Grip Strength test is impossible. The aim is to assess isometric knee extension (IKE) strength as a potential criterion for detecting sarcopenia within the assessment of muscle strength, and to propose a cutoff for diagnosis. Methods. A cross-sectional study was designed and community-dwelling women aged 70 years and over were included. IKE and sarcopenia criteria (EWGSOP2) were assessed. Skeletal muscle mass was assessed by bioelectrical impedance analysis; muscle mass strength by handgrip; and physical performance by the 5 times sit-to-stand test, the Short Physical Performance Battery, and gait speed. The diagnostic accuracy for each sarcopenia criterion was calculated using sensitivity, specificity, positive and negative predictive value, and the area under the curve (AUC). Cutoff points for sarcopenia from IKE were defined with the ROC curve. Results. The sample comprised 94 women with a mean age of 75.9 years (standard deviation 5.6, range 70–92), of whom 25.5% (n = 24) met criteria for sarcopenia—mainly severe sarcopenia (73.8%, n = 17). Correlations were observed between IKE and each individually analyzed sarcopenia criterion except skeletal muscle mass, with AUC values exceeding 0.70 in all cases. The IKE cutoff showing the highest accuracy for the diagnosis of sarcopenia was 12.5 kg or less (AUC 0.76, 95% confidence interval [CI] 0.64–0.88; sensitivity: 65.2%, 95% CI 45.7–84.7; specificity 77.4%, 95% CI 60.3–94.5; positive predictive value 62.5%, 95 CI% 42.7–82.3; negative predictive value 88.8%, 95% CI 75.9–100). Conclusions. IKE could be a suitable tool for measuring muscular strength in sarcopenia when other strength parameters cannot be assessed or in people with walking difficulties. Sarcopenia older women strength isometric knee extension. Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction Sarcopenia is one of the most common age-related musculoskeletal disorders. It is characterized by a reduction in strength and in skeletal muscle mass, which gradually leads to a deterioration in muscle function.[ 1 ] The prevalence of sarcopenia ranges from 10–27% in people aged 60 years or older, and it is higher in men and in people with more comorbidities and dependency.[ 2 ] The association between sarcopenia and different adverse health outcomes, such as increased falls, fractures, respiratory and cardiac diseases, and dependency, along with loss of function and quality of life, have driven efforts to improve detection.[ 3 ] Three criteria are used to diagnose sarcopenia: 1) low muscle strength, 2) low muscle mass, and 3) low physical performance. According to the first European Working Group on Sarcopenia in Older People guidelines (EWGSOP1), the muscle strength parameter was, together with low physical performance, one of two possible confirmatory criteria, while low muscle mass was mandatory. However, in the 2018 update,[ 3 ] muscle strength is now a first-level criterion, while low muscle mass is confirmatory and low physical performance indicates severity. This is because muscle strength decreases three times faster than muscle mass with ageing.[ 4 ] In addition, muscle strength is one of the most reliable measures used by EWGSOP for identifying sarcopenia. However, the recommended tests to measure strength have changed over time. While the EWGSOP1 proposed the use of grip strength, knee flexion/extension strength, and peak expiratory flow;[ 1 ] the EWGSOP2 proposes only the use of grip strength and the chair stand test, while clarifying that isometric torque methods can be used when the grip strength test is not feasible.[ 3 ] Grip strength is a health biomarker in older people;[ 5 ] reduced grip strength has been associated with morbidity and mortality, and it is easy to measure in clinical settings.[ 6 ] Nevertheless, the use of grip strength as the only indicator of overall muscle strength has been criticized, as the association with strength in other body areas is only low to moderate, and this measure has limited sensitivity when monitoring changes in strength and functional performance after resistance training programs—essential interventions for treating sarcopenia. Moreover, some of the most common types of arthritis (osteoarthritis, rheumatoid arthritis, and gout)[ 7 – 10 ] can have a negative impact on grip strength. The other parameter suggested by the EWGSOP2 for assessing muscle strength is the chair stand test, but a common problem with this test is the “ceiling effect”, which occurs when the scores of the test participants are all clustered near the top. In this test, most people complete the test in less than 15 seconds.[ 11 ] In light of these considerations, different authors have suggested complementing the grip strength measurement with a lower limb strength assessment, bearing in mind that the lower limbs are more important than the upper limbs for gait and physical function.[ 1 ] The isometric knee extension (IKE) test may be one such method, as it directly measures the strength of the quadriceps, the lower extremity muscle with the greatest age-related decline in strength (up to 76%). Moreover, it can be measured with isokinetic devices or handheld dynamometers.[ 12 ] While the isokinetic dynamometer is the gold standard for assessing strength, its use is limited due to lack of portability and high costs. A handheld dynamometer is a good alternative, and the IKE test has proven to be a reliable strategy suitable for lower-limb screening in institutionalized older adults. Previous studies have shown a moderate correlation between isokinetic devices and handheld dynamometers for right and left knee extension (r = 0.58–0.75; P < .05). [ 13 ] Based on this finding, the IKE test could represent a sensitive, practical, and affordable approach for evaluating muscle strength during the initial assessment of sarcopenia, and for continuously monitoring this physical capacity during a training program.[ 14 ] Nevertheless, the IKE has not yet been included in algorithms to screen for sarcopenia or assess its severity,[ 3 ] and cutoff values have not been established. This study aims to assess IKE strength as a potential criterion for detecting sarcopenia within the assessment of muscle strength, and to propose a cutoff for diagnosis. Methods This cross-sectional study included older, community-dwelling women in Valencia, Spain. The study was conducted according to the guidelines of the Declaration of Helsinki and approved by the Ethics Committee for Human Research of the University of Valencia (protocol code 1534298 approved 14 January 2021). Following a briefing about the study and its aims, all participants signed informed consent as a precondition for taking part. Participants Women aged 70 years or older who were able to stand independently for 5 minutes for bioelectrical impedance analysis (BIA) were included. Exclusion criteria were: advanced dementia (Global Deterioration Scale score of 7 diagnosed by physician); terminal illness (life expectancy of less than 6 months); implanted pacemaker or desfibrillator; edema or hydration disorders that could affect BIA results; corticosteroid treatment within the previous 30 days;[ 15 ] hearing or visual impairments that could interfere with the study; degenerative muscle diseases or any osteoarticular condition that could condition the performance of the tests, and the presence of any other condition that could entail a risk to the participant. Recruitment took place in primary healthcare centres and social centres for older people between April and December 2021. Assessments took place in dedicated rooms of the University of Valencia Physiotherapy School. In total, 104 older women underwent an assessment; 7 declined to participate, and 3 were excluded for being in poor general health due to acute problems, leaving a final study population of 94 women. Sample size The estimated prevalence of sarcopenia in community-dwelling older people in a Mediterranean geographical area, according to the EWGSOP2 criteria, is 3.2%.[ 16 ] For a margin of error of 5% and a confidence level of 95%, the required sample size is 53 older women (G-Power, Dusseldorf, Germany). Measurements The assessments were performed by two nurses, one physiotherapist, and two physical activity professionals, each with more than 10 years of research experience in studies with older people. Prior to the assessments, all the people involved in the assessments trialled the measurements in 10 women to detect and correct any inter-observer variability. We defined sarcopenia according to EWGSOP2 criteria. This included the Sarc-F questionnaire and measurements of muscle strength, muscle quantity, and physical performance.[ 3 ] The Sarc-F questionnaire comprises five items, eliciting information on strength, the need for assistance in walking, rise from a chair, stair climbing, and falls. Each item is scored from 0 to 2, with total scores of 4 points or more out of a total of 10 points indicating a positive screening result.[ 17 ] The three sarcopenia criteria were measured as specified below. Muscle strength . This criterion was measured as follows. Handgrip strength technique. The Jamar Hydraulic Hand Dynamometer 5030J1 (Loughborough, UK) was used to measure dominant handgrip. We recorded the highest value out of three assessments.[ 18 ] The cutoff was 15 seconds.[ 20 ] This test was performed as part of the Short Physical Performance Battery (SPPB) assessment (detailed below), as it is part of this scale. Maximum isometric knee extension (IKE). A previously calibrated handheld digital dynamometer (model 01165, LaFayette, USA) was used to measure the isometric strength of the dominant leg.[ 21 ] A hip flexion angle of 110° and a knee flexion angle of 60° from the anatomical zero (180°) were maintained.[ 22 ] A pad was placed on the shin 4–5 cm above the tibial malleolus to prevent excessive pain. The best of 5 attempts was analyzed. The handheld dynamometer showed a good degree of internal consistency, with a Cronbach’s alpha of 0.762 and a test-retest reliability (ICC) of 0.96.[ 13 ] Muscle mass . Weight and body weight muscle mass were collected using a previously calibrated BC-418 MA BIA device (Tanita 2016, America). Height was measured with a previously calibrated stadiometer, and body mass index (BMI) was calculated. The skeletal muscle mass index (SMMI) was calculated as muscle mass/height (kg/m 2 ), where low muscle mass was defined as less than 5.5 kg/m 2 . The following criteria were checked prior to the assessment: participants should not engage in physical exercise in the twelve hours prior to the assessment; had not eaten or drunk any alcohol or large quantities of water for 2–3 h; had an empty bladder; and were not wearing any metal items. Physical performance . This variable was assessed by two tests: Walking speed was assessed as follows: the participant walked at her usual pace for a distance of 4 m along a corridor, using a technical aid if needed, from a standing start and without eliminating acceleration and deceleration phases. This test was performed as part of the SPPB assessment (detailed below), but it was performed twice, and the shortest time was recorded, with a cutoff value of less than 0.8 m/s.[ 1 ] SPPB, according to the instructions of Guralnik et al.[ 11 ] It includes three tests, each scored from 0 to 4: a balance test, a walking test, and a repeated chair stand test (5TSTS). In the balance test, the participants were asked to stand with their feet together, in the semi-tandem and tandem positions, and the time they needed to walk 4 m was measured. The cutoff is 8 points or fewer out of a total possible score of 12. Following these assessments, participants were classified according to the EWGSOP2 algorithm.[ 3 ] Specifically, a Sarc-F score of 4 points or more represented a positive screening result, and these participants were classified as having (1) probable sarcopenia in the presence of low muscle strength alone (grip strength 15 s); (2) confirmed sarcopenia when low quantity muscle was also detected (SMMI < 5.5 kg/m2); or (3) severe sarcopenia, when low physical performance was added (gait speed < 0.8 m/s; SPPB ≤ 8 points) (Fig. 1 ). Statistical analysis All data entered into the database were verified by an independent second person. Descriptive statistics were expressed as mean and standard deviation (SD) for normally distributed continuous variables and relative frequencies for categorical variables. Correlations between IKE and the different EWGSOP2 sarcopenia criteria were analyzed separately and in clusters (positive screen, muscle mass strength, and physical performance). The receiver operating characteristics (ROC) curve was used to determine the cutoff value and sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the IKE, each sarcopenia criterion, and sarcopenia criteria clusters. A P value of less than .05 was considered statistically significant. The statistical analysis was carried out with the SPSS Version 26.0 for Windows (IBM Corp., Armonk, NY, USA) and Jamovi 2.2.5 statistical packages. Results The study included 94 women with a mean age of 75.9 years (SD 5.6, range 70–92). Of these, 25.5% (n = 24) were classified as having probable sarcopenia based on the Sarc-F score alone (≥ 4 points). Following the assessment of additional strength and physical performance criteria, 24 participants (25.5%) met criteria for sarcopenia, of whom just 13 (54.2%) had obtined a positive screening result. Of the 24 women with sarcopenia, 73.8% (n = 17) were classified as having severe sarcopenia. Mean age was similar in women with (77.8 years SD 6.37) and without (75.2 years SD 5.2) sarcopenia (Table 1 ). For its part, mean muscle strength, as assessed by IKE, was 15.1 kg (SD 5.2) in the sample as a whole, with a significant difference between women with and without sarcopenia (11.73 kg SD 4.8 vs 16.33 kg SD 4.8 vs; mean difference [MD] − 4.06, 95% confidence interval [CI] − 6.97, − 2.37; P < .001). Table 1 Sarcopenia screening results in the measures for EWGSOP2 sarcopenia criteria: muscle strength, muscle mass and physical performance Total (N = 94) No sarcopenia (n = 70) Sarcopenia (n = 24) P value Screening result Sarc-F points, mean (SD) 2.27 (2.13) 1.85 (1.9) 3.5 (2.34) .001 u Sarc-F ≥ 4 points, n (%) 24 (25.5) 11 (45.8) 13 (19.1) .010 χ2 Skeletal muscle strength Grip strength kg, mean (SD) 19.57 (5.07) 20.62 (4.67) 16.5 (5.01) < .001 u Grip strength < 16 kg, n (%) 19 (20.2) 9 (12.9) 10 (41.7) .002 χ2 5TSTS, seconds, mean (SD) 17.06 (11.48) 15.03 (9.09) 23 (15.36) 15 seconds, n (%) 42 (44.7) 20 (28.6) 22 (91.7) < .001 χ2 IKE*, kg, mean (SD) 15.08 (5.2) 16.33 (4.80) 11.73 (4.80) < .001 t Skeletal muscle mass SMMI predicted by (BIA), kg/m 2 , mean (SD) 5.84 (1.20) 6.19 (1.15) 4.86 (0.71) < .001 t SMMI < 5.5 kg/m 2 , n (%) 24 (25.5) 0 (0) 24 (25.5) < .001 χ2 Physical performance Gait speed seconds, mean (SD) 0.82 (0.25) 0.85 (0.24) 0.75 (0.22) .068 t Gait speed ≤ 0.8m/s, n (%) 44 (46.8) 29 (41.4) 15 (34.1) .074 SPPB points, mean (SD) 9.01 (2.66) 9.49 (2.47) 7.50 (2.65) .001 u SPPB ≤ 8 points, n (%) 36 (38.3) 22 (31.4) 14 (58.3) .019 χ2: Chi square test; t: t-Test; U: Mann-Whitney U test IKE: Maximum isometric knee extension; SMMI: skeletal muscle mass index; SPPB: Short physical performance battery; 5TSTS: 5-times sit-to-stand; * Possible sarcopenia criteria Correlations between IKE and Sarc-F, grip strength, 5TSTS and SPPB were over 0.4, while there was no correlation with SMMI (Fig. 2 and Table 2 ). Table 2 Correlation matrix for EWGSOP2 sarcopenia criteria IKE Sarc-F SMMI Grip Strength 5TSTS Gait Speed SPPB Sarc-F Spearman (Rho) −0.487 — P value < .001 — SMMI R (Pearson) −0.008 — P value .270 — Spearman (Rho) — −0.005 — P value — .535 — Grip Strength Spearman (Rho) 0.452 0.512 0.005 — P value < .001 < .001 .649 — 5TSTS R (Pearson) — 0.622 — — — P value — < .001 — — — Spearman (Rho) −0.408 — 0.048 −0.501 — P value < .001 — 0.762 < .001 — Gait Speed R (Pearson) 0.462 — −0.177 — — — P value < .001 — .088 — — — Spearman (Rho) −0.607 — 0.430 −0.533 — P value < .001 — < .001 < .001 — SPPB Spearman (Rho) 0.499 −0.652 −0.091 0.542 0.757 0.713 — P value < .001 < .001 .419 < .001 < .001 < .001 — IKE: Isometric Knee Extension Strength SMMI: skeletal muscle mass index; SPPB: Short physical performance battery; 5TSTS: 5-times sit-to-stand The ROC curves were analyzed for each EWGSOP2 criterion (Sarc-F, grip strength, 5TSTS, SPPB, gait speed, and SMMI), with the highest curve observed for SMMI (AUC 0.85). Between the two low strength criteria, the highest curve was obtained for the 5TSTS (area under the ROC curve [AUC] 0.78), and between the two low physical performance criteria, it was the SPPB (AUC = 0.72) (Table 3 ). Table 3 Accuracy of IKE and each EWGSOP2 sarcopenia criterion, alone and in clusters Variable AUC (95%CI) Sensitivity (95%CI) Specificity (95%CI) PPV (95%CI) NPV (95%CI) IKE ≤ 12.5 kg 0.76 (0.64–0.88) 65.2 (45.7–84.7) 77.4 (60.3–94.5) 62.5 (42.7–82.3) 88.8 (75.9–100) Positive screen and single sarcopenia criterion Sarc-F ≥ 4 points 0.72 (0.60–0.83) 45.8 (25.9–65.7) 80.9 (65.2–96.6) 45.8 (25.9–65.8) 80.9 (65.2–96.6) SMMI 15 seconds 0.78 (0.68–0.89) 91.7 (80.7–100) 71.4 (53.3–89.5) 52.4 (32.4–72.4) 96.2 (88.5–100) GRIP S < 16 kg 0.74 (0.62–0.86) 41.7 (22.0-61.4) 87.1 (73.7–100) 52.6 (32.7–72.6) 81.3 (65.7–96.9) SPPB ≤ 8 points 0.72 (0.61–0.83) 58.3 (38.6–78.0) 68.6 (50.0-87.2) 38.9 (19.4–58.4) 82.8 (68.0-97.9) GAIT S ≤ 0.8 m/s 0.62 (0.50–0.75) 62.5 (43.1–81.9) 58.6 (38.9–78.3) 34.1 (15.1–53.1) 82.0 (66.6–97.4) Sarcopenia criteria (SSMI + one criterion from skeletal muscle strength) SMMI + GRIP S 0.92 (0.86–0.97) 41.7 (22.0-61.4) 100 (100–100) 100 (100–100) 83.3 (68.1–98.5) SMMI + 5TSTS 0.99 (0.97-1.00) 91.7 (80.66–100) 100 (100–100) 100 (100–100) 97.2 (90.5–100) SMMI + IKE* 0.94 (0.89–0.99) 65.2 (46.1–84.3) 98.6 (93.8–100) 93.8 (83.9–100) 89.5 (77.2–100) Severe sarcopenia criteria (SSMI + one criteria from skeletal muscle strength + one physical performance criteria) SMMI + GRIP S + SPPB 0.98 (0.96-1.00) 82.4 (64.3–100) 100 (100–100) 100 (100–100) 96.3 (87.2–100) SMMI + GRIP S + GAIT S 0.96 (0.92-1.00) 82.4 (64.3–100) 100 (100–100) 100 (100–100) 96.3 (87.2–100) SMMI + 5TSTS + SPPB 0.98 (0.95-1.00) 35.3 (12.5–57.9) 100 (100–100) 100 (100–100) 87.5 (71.8–100) SMMI + 5TSTS + GAIT S 0.99 (0.97-1.00) 47.1 (23.4–70.8) 100 (100–100) 100 (100–100) 89.5 (75.0-100) SMMI + IKE* +SPPB 0.98 (0.95-1.00) 62.5 (39.5–85.5) 100 (100–100) 100 (100–100) 92.8 (80.5–100) SMMI + IKE* + GAIT S 0.99 (0.97-1.00) 64.7 (42.0-87.4) 100 (100–100) 100 (100–100) 92.8 (80.5–100) AUC: area under the curve; GAIT S: Gait speed; GRIP S: Grip strength; IKE: maximum isometric knee extension; PPV: positive predictive value; NPV: negative predictive value; SMMI: skeletal muscle mass index; SPPB: Short Physical Performance Battery; 5TSTS: 5-times sit-to-stand; * Possible sarcopenia criteria The IKE is a measure of low strength within the cluster of sarcopenic criteria. Its AUC value was higher than that for grip strength and lower than that for the 5TSTS. The cutoff point showing the highest sensitivity and specificity for diagnosing sarcopenia was 12.5 kg or less, with an accuracy higher than grip strength (Table 3 ; Fig. 3 and Fig. 4 ). Of the total sample, 34.1% (n = 29) met this IKE criterion: 62.5% (n = 15) of the sarcopenia group, and 20% (n = 14) of the non-sarcopenia group ( P < .001). We then analyzed the AUC of the two recommended sarcopenia strength criteria cluster (grip strength and 5TSTS) and the IKE together (Table 3 ). Discussion The present study proposes IKE cutoff points to diagnose sarcopenia in community-dwelling older women. Using 12.5 kg or lower as a cutoff, we assessed whether the IKE is an appropriate tool for measuring strength in women with sarcopenia, in both clinical practice and in research. The EWGSOP2 recommends using grip strength and 5TSTS as the strength tests for diagnosing sarcopenia but clarifies that isometric torque methods can be used when grip strength is not possible,[ 3 ] and it could even be a suitable screening tool for sarcopenia in people who have difficulty in walking.[ 23 ] Both grip strength and IKE appear to be very sensitive for detecting functionally relevant muscle weakness in older adults. Grip strength is probably most appropriate for monitoring the efficacy of treatments in sedentary populations. However, exercise interventions should be monitored with appropriate regional measures.[ 24 ] In addition, in patients affected by common types of arthritis, grip strength may not be strongly correlated with overall muscle function. Given that these conditions have a relatively high prevalence in the older population, it is of interest to have data that enable the selection of the most appropriate measurements according to the characteristics of the women.[ 25 ] Although to our knowledge, there are no published studies proposing a cutoff for IKE as a possible criterion for sarcopenia, research on the topic is increasing. For example, one study in Thailand studied the reduction in IKE over time in older adults and correlated its values with sarcopenia criteria,[ 23 ] while other authors have used different assessments of knee strength.[ 24 , 26 ] These studies also obtained AUCs of over 0.70, confirming that the quantification of lower limb strength could be a possible criterion for sarcopenia. The sensitivity of grip strength based on the data obtained in our study was 23% less sensitive than IKE. These results are consistent with other studies supporting the suitability of IKE for assessing lower limb strength.[ 27 ] At their onset, functional limitations may be caused by a considerable decrease in the strength of the lower limbs, which is greater than the drop in handgrip strength. Indeed, the estimated reduction in quadriceps strength linked to ageing is 48%, compared to 23% for grip strength.[ 28 ] This reflects the differential age-related loss in strength according to muscle group. When using handgrip strength to assess potential strength loss, we may be underestimating the early loss of strength that actually occurs in the quadriceps.[ 28 ] The importance of assessing performance using IKE has been reported and could be particularly useful in those at high risk of functional decline.[ 27 ] The IKE has been shown to have the highest predictive value against grip strength in assisted living facilities;[ 26 ] however, people in these settings are often approaching or in the early stages of functional limitations. The use of IKE should be considered at the initial stages of sarcopenia, where early detection is essential,[ 29 ] and it is indicated if the person is unable to perform a dynamic squat test(to obtain a general indication of dynamic posture), [ 14 ] which is necessary for tests like the 5TSTS. Given the direct involvement of the knee extensor muscles for actions such as walking or getting up from a chair, its correlation with functional performance in tests such as the 6 m and Time Up and Go (TUG) should not be surprising.[ 14 ] We observed significant correlations between IKE and performance tests (SPPB and gait speed). Buendía-Romero et al. [ 14 ] reported a similar relationship with the TUG and 6-m gait speed tests. Taken together, the data confirm the close relationship between IKE and functional performance. The diagnostic accuracy of the IKE relative to other sarcopenia criteria, whether individually or in clusters, was high in our sample, yielding better values than grip strength as a criterion for low strength in both sarcopenia and severe sarcopenia. The criterion of low muscle strength is associated with higher mortality and worse health outcomes,[ 30 ] so detecting older people at risk is critical for implementing early prevention measures. Assessing IKE with an isokinetic dynamometer is more expensive than using a handheld device (e.g. JAMAR, Smedley). However, its high accuracy [ 14 ] makes it a useful option in cases where the assessment of other low-strength criteria is difficult. It shows better accuracy than grip strength, both as an isolated criterion or in combination with other measures; it can be used in people with walking difficulties; and it is relatively quick to perform, taking only about 5 min/participant. Limitations Our study is not without its limitations. The first is that the analysis was conducted only in women in a community setting. The sarcopenia criteria used were those in the EWGSOP2, so the results using other sarcopenia criteria could be different. Drugs that can affect muscle function, such as statins or psychotropic medication, were also not analyzed. Even though the results obtained are a step forward, there is a need for further studies to identify the best diagnostic tools in both sexes as well as in different settings, and to assess the impact of associated comorbidity and the use of drugs, especially those that could have undesirable adverse effects, such as an increase in muscle weakness. Conclusions The IKE could be a suitable measure of strength in both clinical practice and research settings in patients with sarcopenia, particularly where other strength parameters cannot be assessed or in people with walking difficulties. The cutoff of ≤ 12.5 kg has acceptable diagnostic accuracy for older women in the community setting. Further studies in different sexes and settings are needed. Abbreviations AUC area under the curve EWGSOP1 European Working Group on Sarcopenia in Older People guidelines 1 EWGSOP2 European Working Group on Sarcopenia in Older People guidelines 2 IKE Isometric knee extension PPV Positive predictive value ROC Receiver operating characteristics SPPB Short Physical Performance Battery SMMI Skeletal muscle mass index 5TSTS The 5 times sit-to-stand Declarations ethics approval and consent to participate The study was conducted according to the guidelines of the Declaration of Helsinki and approved by the Ethics Committee for Human Research of the University of Valencia (protocol code 1534298 approved 14 January 2021). Following a briefing about the study and its aims, all participants signed informed consent as a precondition for taking part. Consent for publication Not applicable Availability of data and materials The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request. Competing interests The authors declare that they have no competing interests Funding This work was supported by Conselleria de Innovación, Universidades, Ciencia y Sociedad digital, Valencia, Spain [Grant number GV/2020/071]. Sponsor has no role in the design, methods, subject recruitment, data collections, analysis and preparation of paper. Authors’ contributions Study concept and design: OC, FMMA; Acquisition of data: PPR, JBI, AP, RFV, FMM; Analysis and interpretation of data: PPR, JBI, AP, RFV, FMM; Drafting of the manuscript: PPR, JBI, AP, RFV, FMM; Critical revision of the manuscript for important intellectual content: OC, FMMA Acknowledgements We are grateful to all of the participants, as well as the primary healthcare centers and social centers that participated in the recruitment. References Cruz-Jentoft AJ, Baeyens JP, Bauer JM, Boirie Y, Cederholm T, Landi F, et al. 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Guralnik JM, Simonsick EM, Ferrucci L, Glynn RJ, Berkman LF, Blazer DG, et al. A short physical performance battery assessing lower extremity function: association with self-reported disability and prediction of mortality and nursing home admission. J Gerontol. 1994;49:M85–94. Andrews AW, Thomas MW, Bohannon RW. Normative values for isometric muscle force measurements obtained with hand-held dynamometers. Phys Ther. 1996;76:248–59. Arnold CM, Warkentin KD, Chilibeck PD, Magnus CRA. The reliability and validity of handheld dynamometry for the measurement of lower-extremity muscle strength in older adults. J Strength Cond Res. 2010;24:815–24. Buendía-Romero Á, Hernández-Belmonte A, Martínez-Cava A, García-Conesa S, Franco-López F, Conesa-Ros E, et al. Isometric knee extension test: A practical, repeatable, and suitable tool for lower-limb screening among institutionalized older adults. Exp Gerontol. 2021;155:111575. Salamone IM, Quattrocelli M, Barefield DY, Page PG, Tahtah I, Hadhazy M, et al. Intermittent glucocorticoid treatment enhances skeletal muscle performance through sexually dimorphic mechanisms. J Clin Invest. 2022;132:e149828. Costanzo L, De Vincentis A, Di Iorio A, arnol S, Ferrucci L, Antonelli Incalzi R, et al. Impact of low muscle mass and low muscle strength according to EWGSOP2 and EWGSOP1 in community-dwelling older people. J Gerontol Ser A. 2020;75:1324–30. Malmstrom TK, Miller DK, Simonsick EM, Ferrucci L, Morley JE. SARC-F: a symptom score to predict persons with sarcopenia at risk for poor functional outcomes. J Cachexia Sarcopenia Muscle. 2016;7:28–36. Roberts HC, Denison HJ, Martin HJ, Patel HP, Syddall H, Cooper C, et al. A review of the measurement of grip strength in clinical and epidemiological studies: towards a standardised approach. Age Ageing. 2011;40:423–9. Dodds RM, Syddall HE, Cooper R, Benzeval M, Deary IJ, Dennison EM, et al. Grip strength across the life course: normative data from twelve British studies. PLoS ONE. 2014;9:e113637. Cesari M, Kritchevsky SB, Newman AB, Simonsick EM, Harris TB, Penninx BW, et al. Added value of physical performance measures in predicting adverse health-related events: results from the health, aging and body composition study. J Am Geriatr Soc. 2009;57:251–9. Bohannon RW. Hand-held dynamometry: A practicable alternative for obtaining objective measures of muscle strength. Isokinet Exerc Sci. 2012;20:301–15. Francis P, Toomey C, Mc Cormack W, Lyons M, Jakeman P. Measurement of maximal isometric torque and muscle quality of the knee extensors and flexors in healthy 50- to 70-year-old women. Clin Physiol Funct Imaging. 2017;37:448–55. Assantachai P, Muangpaisan W, Intalapaporn S, Sitthichai K, Udompunturak S. Cut-off points of quadriceps strength, declines and relationships of sarcopenia-related variables among Thai community-dwelling older adults. Geriatr Gerontol Int. 2014;14(Suppl 1):61–8. Abdalla PP, Dos Santos Carvalho A, Dos Santos AP, Venturini ACR, Alves TC, Mota J, et al. Cut-off points of knee extension strength allometrically adjusted to identify sarcopenia risk in older adults: A cross-sectional study. Arch Gerontol Geriatr. 2020;89:104100. Carvalho do Nascimento PR, Bilodeau M, Poitras S. How do we define and measure sarcopenia? A meta-analysis of observational studies. Age Ageing. 2021;50:1906–13. Lauretani F, Russo CR, Bandinelli S, Bartali B, Cavazzini C, Di Iorio A, et al. Age-associated changes in skeletal muscles and their effect on mobility: an operational diagnosis of sarcopenia. J Appl Physiol. 2003;95:1851–60. Martien S, Delecluse C, Boen F, Seghers J, Pelssers J, Van Hoecke A-S, et al. Is knee extension strength a better predictor of functional performance than handgrip strength among older adults in three different settings? Arch Gerontol Geriatr. 2015;60:252–8. Samuel D, Wilson K, Martin HJ, Allen R, Sayer AA, Stokes M. Age-associated changes in hand grip and quadriceps muscle strength ratios in healthy adults. Aging Clin Exp Res. 2012;24:245–50. Evans W. Functional and metabolic consequences of sarcopenia. J Nutr. 1997;127(5 Suppl):998S–1003S. Spexoto MCB, Ramírez PC, de Oliveira Máximo R, Steptoe A, de Oliveira C, Alexandre TdaS. European Working Group on Sarcopenia in Older People 2010 (EWGSOP1) and 2019 (EWGSOP2) criteria or slowness: which is the best predictor of mortality risk in older adults? Age Ageing. 2022;51:afac164. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 02 Dec, 2024 Read the published version in BMC Geriatrics → Version 1 posted Editorial decision: Revision requested 20 Oct, 2024 Reviews received at journal 18 Oct, 2024 Reviewers agreed at journal 04 Oct, 2024 Reviews received at journal 21 Sep, 2024 Reviewers agreed at journal 16 Sep, 2024 Reviewers agreed at journal 07 May, 2024 Reviewers agreed at journal 02 May, 2024 Reviewers invited by journal 25 Apr, 2024 Editor assigned by journal 25 Apr, 2024 Editor invited by journal 19 Jan, 2024 Submission checks completed at journal 19 Jan, 2024 First submitted to journal 13 Jan, 2024 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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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-3860792","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":267975969,"identity":"4f8b5cd1-d92c-4283-8a9d-8eab810aa88c","order_by":0,"name":"Pilar Pérez-Ros","email":"","orcid":"","institution":"Universitat de València","correspondingAuthor":false,"prefix":"","firstName":"Pilar","middleName":"","lastName":"Pérez-Ros","suffix":""},{"id":267975970,"identity":"a2b49ebc-d89d-4f28-b7d4-baf5f513cbad","order_by":1,"name":"Joaquín Barrachina-Igual","email":"","orcid":"","institution":"Universidad Católica de Valencia San Vicente Mártir","correspondingAuthor":false,"prefix":"","firstName":"Joaquín","middleName":"","lastName":"Barrachina-Igual","suffix":""},{"id":267975971,"identity":"594fa94b-a1e3-4e5c-a44f-62f1cd971eb6","order_by":2,"name":"Ana Pablos","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAzklEQVRIiWNgGAWjYPCCAzIMDMwHSNPCw8DAlkCyFh4D4tTyz25+wFxQc4eHn//MN4mfbQxy8g0EtEjcOWbAPOPYMx7JGbnbJHvbGIwNDhCy5kaCATMP22Eegxu826QZzjAkbiCkQ/5G+gdmnn9ALefPPANpqZ9PyGEGN3IMmHnbgFoO5LBJM1QwJDAQcpjhjZyCwzP7QH5JM7bsqZAw3EBIi9yN9I2PC77dkePnP/zwxg8DG3mCIQYCh5HYEkSoBwJm4pSNglEwCkbBiAUA4gY9yzHmTFQAAAAASUVORK5CYII=","orcid":"","institution":"Universidad Católica de Valencia San Vicente Mártir","correspondingAuthor":true,"prefix":"","firstName":"Ana","middleName":"","lastName":"Pablos","suffix":""},{"id":267975972,"identity":"c4a2fb5d-3537-49e2-9112-7b7712cca5ff","order_by":3,"name":"Rosa Fonfria-Vivas","email":"","orcid":"","institution":"Universitat de València","correspondingAuthor":false,"prefix":"","firstName":"Rosa","middleName":"","lastName":"Fonfria-Vivas","suffix":""},{"id":267975973,"identity":"d1267337-87c2-4d5e-b132-8a3557435b05","order_by":4,"name":"Omar Cauli","email":"","orcid":"","institution":"Universitat de València","correspondingAuthor":false,"prefix":"","firstName":"Omar","middleName":"","lastName":"Cauli","suffix":""},{"id":267975974,"identity":"829f1c98-ca67-44c5-aab7-073ab33665ed","order_by":5,"name":"Francisco M Martínez-Arnau","email":"","orcid":"","institution":"Universitat de València","correspondingAuthor":false,"prefix":"","firstName":"Francisco","middleName":"M","lastName":"Martínez-Arnau","suffix":""}],"badges":[],"createdAt":"2024-01-13 17:14:13","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-3860792/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-3860792/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s12877-024-05569-y","type":"published","date":"2024-12-02T15:57:53+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":49980865,"identity":"bf39be2f-a09f-45b4-b9fd-0b87af425cfa","added_by":"auto","created_at":"2024-01-22 15:36:43","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":35946,"visible":true,"origin":"","legend":"\u003cp\u003eSarcopenia screening and diagnostic criteria using EWGSOP2 algorithm.\u003c/p\u003e\n\u003cp\u003eNote\u003cstrong\u003e:\u003c/strong\u003e ASM: appendicular skeletal muscle mass; EWGSOP2: European Working Group on Sarcopenia in Older People; SMMI: skeletal muscle mass index; SPPB: Short Physical Performance Battery.\u003c/p\u003e","description":"","filename":"OnlineFigure1.png","url":"https://assets-eu.researchsquare.com/files/rs-3860792/v1/7cfa9bcf914874948550e4f3.png"},{"id":49981392,"identity":"f7ad2518-8d33-411f-9b94-0a1d7a519bb6","added_by":"auto","created_at":"2024-01-22 15:44:43","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":53750,"visible":true,"origin":"","legend":"\u003cp\u003eCorrelations between Isometric Knee Extension and each EWGSOP2 sarcopenia criteria.\u003c/p\u003e\n\u003cp\u003eNote\u003cstrong\u003e:\u003c/strong\u003e GSpeed: gait speed; GStrength: grip strength; IKE: Isometric Knee Extension Strength; SMMI: skeletal muscle mass index; SPPB: Short Physical Performance Battery; 5TSTS: 5-times sit-to-stand, r= Pearson correlation; ρ= Spearman correlation; ***: significant at \u003cem\u003eP \u003c/em\u003e\u0026lt; .001\u003c/p\u003e","description":"","filename":"OnlineFigure2.png","url":"https://assets-eu.researchsquare.com/files/rs-3860792/v1/97be59664d30e126b92d8f28.png"},{"id":49980864,"identity":"97dc663b-b5d2-48bf-80ee-0e6a41196302","added_by":"auto","created_at":"2024-01-22 15:36:43","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":100178,"visible":true,"origin":"","legend":"\u003cp\u003eROC curve for strength sarcopenia criteria.\u003c/p\u003e\n\u003cp\u003eNote\u003cstrong\u003e:\u003c/strong\u003e 5TSTS: 5-times sit-to-stand; IKE: isometric knee strength\u003c/p\u003e","description":"","filename":"OnlineFigure3.png","url":"https://assets-eu.researchsquare.com/files/rs-3860792/v1/ecddf6b3bea19e240856b2b2.png"},{"id":49980862,"identity":"306a1ba5-55d3-4a4b-8e26-408843792d44","added_by":"auto","created_at":"2024-01-22 15:36:43","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":44752,"visible":true,"origin":"","legend":"\u003cp\u003ea) ROC curve and b) cutoff for Isometric Knee Extension according to EWGSOP2 sarcopenia diagnosis.\u003c/p\u003e","description":"","filename":"OnlineFigure4.png","url":"https://assets-eu.researchsquare.com/files/rs-3860792/v1/65ba922eff2bae2b12634a1b.png"},{"id":70964762,"identity":"1ffacfdd-b07f-4180-b8c4-df4f050e458e","added_by":"auto","created_at":"2024-12-09 16:15:31","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":915102,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3860792/v1/89d15237-10e8-4d9b-b46e-3883893bdcd6.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Diagnostic accuracy of isometric knee extension strength as a sarcopenia criteria in community-dwelling older women","fulltext":[{"header":"Introduction","content":"\u003cp\u003eSarcopenia is one of the most common age-related musculoskeletal disorders. It is characterized by a reduction in strength and in skeletal muscle mass, which gradually leads to a deterioration in muscle function.[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e] The prevalence of sarcopenia ranges from 10\u0026ndash;27% in people aged 60 years or older, and it is higher in men and in people with more comorbidities and dependency.[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e] The association between sarcopenia and different adverse health outcomes, such as increased falls, fractures, respiratory and cardiac diseases, and dependency, along with loss of function and quality of life, have driven efforts to improve detection.[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e] Three criteria are used to diagnose sarcopenia: 1) low muscle strength, 2) low muscle mass, and 3) low physical performance. According to the first European Working Group on Sarcopenia in Older People guidelines (EWGSOP1), the muscle strength parameter was, together with low physical performance, one of two possible confirmatory criteria, while low muscle mass was mandatory. However, in the 2018 update,[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e] muscle strength is now a first-level criterion, while low muscle mass is confirmatory and low physical performance indicates severity. This is because muscle strength decreases three times faster than muscle mass with ageing.[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e] In addition, muscle strength is one of the most reliable measures used by EWGSOP for identifying sarcopenia. However, the recommended tests to measure strength have changed over time. While the EWGSOP1 proposed the use of grip strength, knee flexion/extension strength, and peak expiratory flow;[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e] the EWGSOP2 proposes only the use of grip strength and the chair stand test, while clarifying that isometric torque methods can be used when the grip strength test is not feasible.[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eGrip strength is a health biomarker in older people;[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e] reduced grip strength has been associated with morbidity and mortality, and it is easy to measure in clinical settings.[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e] Nevertheless, the use of grip strength as the only indicator of overall muscle strength has been criticized, as the association with strength in other body areas is only low to moderate, and this measure has limited sensitivity when monitoring changes in strength and functional performance after resistance training programs\u0026mdash;essential interventions for treating sarcopenia. Moreover, some of the most common types of arthritis (osteoarthritis, rheumatoid arthritis, and gout)[\u003cspan additionalcitationids=\"CR8 CR9\" citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e] can have a negative impact on grip strength. The other parameter suggested by the EWGSOP2 for assessing muscle strength is the chair stand test, but a common problem with this test is the \u0026ldquo;ceiling effect\u0026rdquo;, which occurs when the scores of the test participants are all clustered near the top. In this test, most people complete the test in less than 15 seconds.[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eIn light of these considerations, different authors have suggested complementing the grip strength measurement with a lower limb strength assessment, bearing in mind that the lower limbs are more important than the upper limbs for gait and physical function.[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e] The isometric knee extension (IKE) test may be one such method, as it directly measures the strength of the quadriceps, the lower extremity muscle with the greatest age-related decline in strength (up to 76%). Moreover, it can be measured with isokinetic devices or handheld dynamometers.[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e] While the isokinetic dynamometer is the gold standard for assessing strength, its use is limited due to lack of portability and high costs. A handheld dynamometer is a good alternative, and the IKE test has proven to be a reliable strategy suitable for lower-limb screening in institutionalized older adults. Previous studies have shown a moderate correlation between isokinetic devices and handheld dynamometers for right and left knee extension (r\u0026thinsp;=\u0026thinsp;0.58\u0026ndash;0.75; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;.05). [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e] Based on this finding, the IKE test could represent a sensitive, practical, and affordable approach for evaluating muscle strength during the initial assessment of sarcopenia, and for continuously monitoring this physical capacity during a training program.[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e] Nevertheless, the IKE has not yet been included in algorithms to screen for sarcopenia or assess its severity,[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e] and cutoff values have not been established.\u003c/p\u003e \u003cp\u003eThis study aims to assess IKE strength as a potential criterion for detecting sarcopenia within the assessment of muscle strength, and to propose a cutoff for diagnosis.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003eThis cross-sectional study included older, community-dwelling women in Valencia, Spain. The study was conducted according to the guidelines of the Declaration of Helsinki and approved by the Ethics Committee for Human Research of the University of Valencia (protocol code 1534298 approved 14 January 2021). Following a briefing about the study and its aims, all participants signed informed consent as a precondition for taking part.\u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eParticipants\u003c/h2\u003e \u003cp\u003eWomen aged 70 years or older who were able to stand independently for 5 minutes for bioelectrical impedance analysis (BIA) were included. Exclusion criteria were: advanced dementia (Global Deterioration Scale score of 7 diagnosed by physician); terminal illness (life expectancy of less than 6 months); implanted pacemaker or desfibrillator; edema or hydration disorders that could affect BIA results; corticosteroid treatment within the previous 30 days;[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e] hearing or visual impairments that could interfere with the study; degenerative muscle diseases or any osteoarticular condition that could condition the performance of the tests, and the presence of any other condition that could entail a risk to the participant.\u003c/p\u003e \u003cp\u003eRecruitment took place in primary healthcare centres and social centres for older people between April and December 2021. Assessments took place in dedicated rooms of the University of Valencia Physiotherapy School. In total, 104 older women underwent an assessment; 7 declined to participate, and 3 were excluded for being in poor general health due to acute problems, leaving a final study population of 94 women.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003eSample size\u003c/h2\u003e \u003cp\u003eThe estimated prevalence of sarcopenia in community-dwelling older people in a Mediterranean geographical area, according to the EWGSOP2 criteria, is 3.2%.[\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e] For a margin of error of 5% and a confidence level of 95%, the required sample size is 53 older women (G-Power, Dusseldorf, Germany).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eMeasurements\u003c/h2\u003e \u003cp\u003eThe assessments were performed by two nurses, one physiotherapist, and two physical activity professionals, each with more than 10 years of research experience in studies with older people. Prior to the assessments, all the people involved in the assessments trialled the measurements in 10 women to detect and correct any inter-observer variability.\u003c/p\u003e \u003cp\u003eWe defined sarcopenia according to EWGSOP2 criteria. This included the Sarc-F questionnaire and measurements of muscle strength, muscle quantity, and physical performance.[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e] The Sarc-F questionnaire comprises five items, eliciting information on strength, the need for assistance in walking, rise from a chair, stair climbing, and falls. Each item is scored from 0 to 2, with total scores of 4 points or more out of a total of 10 points indicating a positive screening result.[\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eThe three sarcopenia criteria were measured as specified below.\u003c/p\u003e \u003cp\u003e \u003cem\u003eMuscle strength\u003c/em\u003e. This criterion was measured as follows.\u003c/p\u003e \u003cp\u003e \u003cul\u003e \u003cli\u003e \u003cp\u003eHandgrip strength technique. The Jamar Hydraulic Hand Dynamometer 5030J1 (Loughborough, UK) was used to measure dominant handgrip. We recorded the highest value out of three assessments.[\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e] The cutoff was \u0026lt;\u0026thinsp;16 kg.[\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003eThe 5 times sit-to-stand (5TSTS) test, in which the participant stood up and sat down on a chair 5 times as quickly as possible, and the total time spent was recorded. The cutoff was \u0026gt;\u0026thinsp;15 seconds.[\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e] This test was performed as part of the Short Physical Performance Battery (SPPB) assessment (detailed below), as it is part of this scale.\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003eMaximum isometric knee extension (IKE). A previously calibrated handheld digital dynamometer (model 01165, LaFayette, USA) was used to measure the isometric strength of the dominant leg.[\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e] A hip flexion angle of 110\u0026deg; and a knee flexion angle of 60\u0026deg; from the anatomical zero (180\u0026deg;) were maintained.[\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e] A pad was placed on the shin 4\u0026ndash;5 cm above the tibial malleolus to prevent excessive pain. The best of 5 attempts was analyzed. The handheld dynamometer showed a good degree of internal consistency, with a Cronbach\u0026rsquo;s alpha of 0.762 and a test-retest reliability (ICC) of 0.96.[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]\u003c/p\u003e \u003c/li\u003e \u003c/ul\u003e \u003c/p\u003e \u003cp\u003e \u003cem\u003eMuscle mass\u003c/em\u003e. Weight and body weight muscle mass were collected using a previously calibrated BC-418 MA BIA device (Tanita 2016, America). Height was measured with a previously calibrated stadiometer, and body mass index (BMI) was calculated. The skeletal muscle mass index (SMMI) was calculated as muscle mass/height (kg/m\u003csup\u003e2\u003c/sup\u003e), where low muscle mass was defined as less than 5.5 kg/m\u003csup\u003e2\u003c/sup\u003e. The following criteria were checked prior to the assessment: participants should not engage in physical exercise in the twelve hours prior to the assessment; had not eaten or drunk any alcohol or large quantities of water for 2\u0026ndash;3 h; had an empty bladder; and were not wearing any metal items.\u003c/p\u003e \u003cp\u003e \u003cem\u003ePhysical performance\u003c/em\u003e. This variable was assessed by two tests:\u003c/p\u003e \u003cp\u003e \u003cul\u003e \u003cli\u003e \u003cp\u003eWalking speed was assessed as follows: the participant walked at her usual pace for a distance of 4 m along a corridor, using a technical aid if needed, from a standing start and without eliminating acceleration and deceleration phases. This test was performed as part of the SPPB assessment (detailed below), but it was performed twice, and the shortest time was recorded, with a cutoff value of less than 0.8 m/s.[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003eSPPB, according to the instructions of Guralnik et al.[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e] It includes three tests, each scored from 0 to 4: a balance test, a walking test, and a repeated chair stand test (5TSTS). In the balance test, the participants were asked to stand with their feet together, in the semi-tandem and tandem positions, and the time they needed to walk 4 m was measured. The cutoff is 8 points or fewer out of a total possible score of 12.\u003c/p\u003e \u003c/li\u003e \u003c/ul\u003e \u003c/p\u003e \u003cp\u003eFollowing these assessments, participants were classified according to the EWGSOP2 algorithm.[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e] Specifically, a Sarc-F score of 4 points or more represented a positive screening result, and these participants were classified as having (1) probable sarcopenia in the presence of low muscle strength alone (grip strength\u0026thinsp;\u0026lt;\u0026thinsp;16 kg or 5TSTS\u0026thinsp;\u0026gt;\u0026thinsp;15 s); (2) confirmed sarcopenia when low quantity muscle was also detected (SMMI\u0026thinsp;\u0026lt;\u0026thinsp;5.5 kg/m2); or (3) severe sarcopenia, when low physical performance was added (gait speed\u0026thinsp;\u0026lt;\u0026thinsp;0.8 m/s; SPPB\u0026thinsp;\u0026le;\u0026thinsp;8 points) (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eAll data entered into the database were verified by an independent second person. Descriptive statistics were expressed as mean and standard deviation (SD) for normally distributed continuous variables and relative frequencies for categorical variables.\u003c/p\u003e \u003cp\u003eCorrelations between IKE and the different EWGSOP2 sarcopenia criteria were analyzed separately and in clusters (positive screen, muscle mass strength, and physical performance). The receiver operating characteristics (ROC) curve was used to determine the cutoff value and sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the IKE, each sarcopenia criterion, and sarcopenia criteria clusters. A \u003cem\u003eP\u003c/em\u003e value of less than .05 was considered statistically significant. The statistical analysis was carried out with the SPSS Version 26.0 for Windows (IBM Corp., Armonk, NY, USA) and Jamovi 2.2.5 statistical packages.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eThe study included 94 women with a mean age of 75.9 years (SD 5.6, range 70\u0026ndash;92). Of these, 25.5% (n\u0026thinsp;=\u0026thinsp;24) were classified as having probable sarcopenia based on the Sarc-F score alone (\u0026ge;\u0026thinsp;4 points). Following the assessment of additional strength and physical performance criteria, 24 participants (25.5%) met criteria for sarcopenia, of whom just 13 (54.2%) had obtined a positive screening result. Of the 24 women with sarcopenia, 73.8% (n\u0026thinsp;=\u0026thinsp;17) were classified as having severe sarcopenia.\u003c/p\u003e \u003cp\u003eMean age was similar in women with (77.8 years SD 6.37) and without (75.2 years SD 5.2) sarcopenia (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). For its part, mean muscle strength, as assessed by IKE, was 15.1 kg (SD 5.2) in the sample as a whole, with a significant difference between women with and without sarcopenia (11.73 kg SD 4.8 vs 16.33 kg SD 4.8 vs; mean difference [MD]\u0026thinsp;\u0026minus;\u0026thinsp;4.06, 95% confidence interval [CI]\u0026thinsp;\u0026minus;\u0026thinsp;6.97, \u0026minus;\u0026thinsp;2.37; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;.001).\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\u003eSarcopenia screening results in the measures for EWGSOP2 sarcopenia criteria: muscle strength, muscle mass and physical performance\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\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 \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003cp\u003e(N\u0026thinsp;=\u0026thinsp;94)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eNo sarcopenia\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;70)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eSarcopenia\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;24)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eScreening result\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSarc-F points, mean (SD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.27 (2.13)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.85 (1.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e3.5 (2.34)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e.001\u003csup\u003eu\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSarc-F\u0026thinsp;\u0026ge;\u0026thinsp;4 points, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e24 (25.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e11 (45.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e13 (19.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e.010 \u003csup\u003eχ2\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"4\" rowspan=\"5\"\u003e \u003cp\u003eSkeletal muscle strength\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eGrip strength kg, mean (SD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e19.57 (5.07)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e20.62 (4.67)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e16.5 (5.01)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt; .001\u003csup\u003eu\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eGrip strength\u0026thinsp;\u0026lt;\u0026thinsp;16 kg, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e19 (20.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e9 (12.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e10 (41.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e.002\u003csup\u003eχ2\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5TSTS, seconds, mean (SD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e17.06 (11.48)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e15.03 (9.09)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e23 (15.36)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt; .001\u003csup\u003eu\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5TSTS\u0026thinsp;\u0026gt;\u0026thinsp;15 seconds, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e42 (44.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e20 (28.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e22 (91.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt; .001\u003csup\u003eχ2\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eIKE*, kg, mean (SD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e15.08 (5.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e16.33 (4.80)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e11.73 (4.80)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt; .001\u003csup\u003et\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eSkeletal muscle mass\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSMMI predicted by (BIA), kg/m\u003csup\u003e2\u003c/sup\u003e, mean (SD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5.84 (1.20)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e6.19 (1.15)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e4.86 (0.71)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt; .001\u003csup\u003et\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSMMI\u0026thinsp;\u0026lt;\u0026thinsp;5.5 kg/m\u003csup\u003e2\u003c/sup\u003e, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e24 (25.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0 (0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e24 (25.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt; .001\u003csup\u003eχ2\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"3\" rowspan=\"4\"\u003e \u003cp\u003ePhysical performance\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eGait speed seconds, mean (SD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.82 (0.25)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.85 (0.24)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.75 (0.22)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e.068\u003csup\u003et\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eGait speed\u0026thinsp;\u0026le;\u0026thinsp;0.8m/s, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e44 (46.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e29 (41.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e15 (34.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e.074\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSPPB points, mean (SD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9.01 (2.66)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e9.49 (2.47)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e7.50 (2.65)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e.001\u003csup\u003eu\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSPPB\u0026thinsp;\u0026le;\u0026thinsp;8 points, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e36 (38.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e22 (31.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e14 (58.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e.019\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e \u003cp\u003eχ2: Chi square test; t: t-Test; U: Mann-Whitney U test\u003c/p\u003e \u003cp\u003eIKE: Maximum isometric knee extension; SMMI: skeletal muscle mass index; SPPB: Short physical performance battery; 5TSTS: 5-times sit-to-stand; * Possible sarcopenia criteria\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eCorrelations between IKE and Sarc-F, grip strength, 5TSTS and SPPB were over 0.4, while there was no correlation with SMMI (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e and Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\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\u003eCorrelation matrix for EWGSOP2 sarcopenia criteria\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"9\"\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 \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\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\" colname=\"c3\"\u003e \u003cp\u003eIKE\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eSarc-F\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eSMMI\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eGrip Strength\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003e5TSTS\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eGait Speed\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003eSPPB\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eSarc-F\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSpearman (Rho)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026minus;0.487\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \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 \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \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 \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"3\" rowspan=\"4\"\u003e \u003cp\u003eSMMI\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eR (Pearson)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026minus;0.008\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \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 \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e.270\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \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 \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSpearman (Rho)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026minus;0.005\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \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 \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e.535\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \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 \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eGrip Strength\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSpearman (Rho)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.452\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.512\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.005\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.649\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"3\" rowspan=\"4\"\u003e \u003cp\u003e5TSTS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eR (Pearson)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.622\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSpearman (Rho)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026minus;0.408\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.048\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026minus;0.501\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.762\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"3\" rowspan=\"4\"\u003e \u003cp\u003eGait Speed\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eR (Pearson)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.462\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026minus;0.177\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.088\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSpearman (Rho)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026minus;0.607\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.430\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u0026minus;0.533\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eSPPB\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSpearman (Rho)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.499\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026minus;0.652\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u0026minus;0.091\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.542\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.757\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.713\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e.419\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u0026mdash;\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"9\" nameend=\"c9\" namest=\"c1\"\u003e \u003cp\u003eIKE: Isometric Knee Extension Strength SMMI: skeletal muscle mass index; SPPB: Short physical performance battery; 5TSTS: 5-times sit-to-stand\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe ROC curves were analyzed for each EWGSOP2 criterion (Sarc-F, grip strength, 5TSTS, SPPB, gait speed, and SMMI), with the highest curve observed for SMMI (AUC 0.85). Between the two low strength criteria, the highest curve was obtained for the 5TSTS (area under the ROC curve [AUC] 0.78), and between the two low physical performance criteria, it was the SPPB (AUC\u0026thinsp;=\u0026thinsp;0.72) (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\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\u003eAccuracy of IKE and each EWGSOP2 sarcopenia criterion, alone and in clusters\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"12\"\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 \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c12\" colnum=\"12\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c3\" namest=\"c1\"\u003e \u003cp\u003eVariable\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eAUC (95%CI)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eSensitivity (95%CI)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003eSpecificity (95%CI)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c10\" namest=\"c8\"\u003e \u003cp\u003ePPV (95%CI)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c11\"\u003e \u003cp\u003eNPV (95%CI)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"1\" nameend=\"c12\" namest=\"c12\"\u003e\u0026nbsp;\u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIKE\u0026thinsp;\u0026le;\u0026thinsp;12.5 kg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003e0.76 (0.64\u0026ndash;0.88)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e65.2 (45.7\u0026ndash;84.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c8\" namest=\"c7\"\u003e \u003cp\u003e77.4 (60.3\u0026ndash;94.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c10\" namest=\"c9\"\u003e \u003cp\u003e62.5 (42.7\u0026ndash;82.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e88.8 (75.9\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c12\" namest=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"11\" nameend=\"c11\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003ePositive screen and single sarcopenia criterion\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c12\" namest=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSarc-F\u0026thinsp;\u0026ge;\u0026thinsp;4 points\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003e0.72 (0.60\u0026ndash;0.83)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e45.8 (25.9\u0026ndash;65.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c9\" namest=\"c7\"\u003e \u003cp\u003e80.9 (65.2\u0026ndash;96.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e45.8 (25.9\u0026ndash;65.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e80.9 (65.2\u0026ndash;96.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c12\" namest=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSMMI\u0026thinsp;\u0026lt;\u0026thinsp;5.5 kg/m\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003e0.85 (0.78\u0026ndash;0.93)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e100 (100\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c9\" namest=\"c7\"\u003e \u003cp\u003e71.4 (53.3\u0026ndash;89.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e54.5 (36.6\u0026ndash;74.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e100 (100\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c12\" namest=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e5TSTS\u0026thinsp;\u0026gt;\u0026thinsp;15 seconds\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003e0.78 (0.68\u0026ndash;0.89)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e91.7 (80.7\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c9\" namest=\"c7\"\u003e \u003cp\u003e71.4 (53.3\u0026ndash;89.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e52.4 (32.4\u0026ndash;72.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e96.2 (88.5\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c12\" namest=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGRIP S\u0026thinsp;\u0026lt;\u0026thinsp;16 kg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003e0.74 (0.62\u0026ndash;0.86)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e41.7 (22.0-61.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c9\" namest=\"c7\"\u003e \u003cp\u003e87.1 (73.7\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e52.6 (32.7\u0026ndash;72.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e81.3 (65.7\u0026ndash;96.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c12\" namest=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSPPB\u0026thinsp;\u0026le;\u0026thinsp;8 points\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003e0.72 (0.61\u0026ndash;0.83)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e58.3 (38.6\u0026ndash;78.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c9\" namest=\"c7\"\u003e \u003cp\u003e68.6 (50.0-87.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e38.9 (19.4\u0026ndash;58.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e82.8 (68.0-97.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c12\" namest=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGAIT S\u0026thinsp;\u0026le;\u0026thinsp;0.8 m/s\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003e0.62 (0.50\u0026ndash;0.75)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e62.5 (43.1\u0026ndash;81.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c9\" namest=\"c7\"\u003e \u003cp\u003e58.6 (38.9\u0026ndash;78.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e34.1 (15.1\u0026ndash;53.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e82.0 (66.6\u0026ndash;97.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c12\" namest=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"11\" nameend=\"c11\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eSarcopenia criteria (SSMI\u0026thinsp;+\u0026thinsp;one criterion from skeletal muscle strength)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c12\" namest=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSMMI\u0026thinsp;+\u0026thinsp;GRIP S\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003e0.92 (0.86\u0026ndash;0.97)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e41.7 (22.0-61.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c9\" namest=\"c7\"\u003e \u003cp\u003e100 (100\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e100 (100\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e83.3 (68.1\u0026ndash;98.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c12\" namest=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSMMI\u0026thinsp;+\u0026thinsp;5TSTS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003e0.99 (0.97-1.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e91.7 (80.66\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c9\" namest=\"c7\"\u003e \u003cp\u003e100 (100\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e100 (100\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e97.2 (90.5\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c12\" namest=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSMMI\u0026thinsp;+\u0026thinsp;\u003cem\u003eIKE*\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003e0.94 (0.89\u0026ndash;0.99)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e65.2 (46.1\u0026ndash;84.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c9\" namest=\"c7\"\u003e \u003cp\u003e98.6 (93.8\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e93.8 (83.9\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e89.5 (77.2\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c12\" namest=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"11\" nameend=\"c11\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eSevere sarcopenia criteria (SSMI\u0026thinsp;+\u0026thinsp;one criteria from skeletal muscle strength\u0026thinsp;+\u0026thinsp;one physical performance criteria)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c12\" namest=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eSMMI\u0026thinsp;+\u0026thinsp;GRIP S\u0026thinsp;+\u0026thinsp;SPPB\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e0.98 (0.96-1.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e82.4 (64.3\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c9\" namest=\"c7\"\u003e \u003cp\u003e100 (100\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e100 (100\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e96.3 (87.2\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c12\" namest=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eSMMI\u0026thinsp;+\u0026thinsp;GRIP S\u0026thinsp;+\u0026thinsp;GAIT S\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e0.96 (0.92-1.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e82.4 (64.3\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c9\" namest=\"c7\"\u003e \u003cp\u003e100 (100\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e100 (100\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e96.3 (87.2\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c12\" namest=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eSMMI\u0026thinsp;+\u0026thinsp;5TSTS\u0026thinsp;+\u0026thinsp;SPPB\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e0.98 (0.95-1.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e35.3 (12.5\u0026ndash;57.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c9\" namest=\"c7\"\u003e \u003cp\u003e100 (100\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e100 (100\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e87.5 (71.8\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c12\" namest=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eSMMI\u0026thinsp;+\u0026thinsp;5TSTS\u0026thinsp;+\u0026thinsp;GAIT S\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e0.99 (0.97-1.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e47.1 (23.4\u0026ndash;70.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c9\" namest=\"c7\"\u003e \u003cp\u003e100 (100\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e100 (100\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e89.5 (75.0-100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c12\" namest=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eSMMI\u0026thinsp;+\u0026thinsp;\u003cem\u003eIKE*\u003c/em\u003e +SPPB\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e0.98 (0.95-1.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e62.5 (39.5\u0026ndash;85.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c9\" namest=\"c7\"\u003e \u003cp\u003e100 (100\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e100 (100\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e92.8 (80.5\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c12\" namest=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eSMMI\u0026thinsp;\u003cem\u003e+\u0026thinsp;IKE*\u003c/em\u003e + GAIT S\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e0.99 (0.97-1.00)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e64.7 (42.0-87.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c9\" namest=\"c7\"\u003e \u003cp\u003e100 (100\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e100 (100\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e92.8 (80.5\u0026ndash;100)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c12\" namest=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"12\" nameend=\"c12\" namest=\"c1\"\u003e \u003cp\u003eAUC: area under the curve; GAIT S: Gait speed; GRIP S: Grip strength; IKE: maximum isometric knee extension; PPV: positive predictive value; NPV: negative predictive value; SMMI: skeletal muscle mass index; SPPB: Short Physical Performance Battery; 5TSTS: 5-times sit-to-stand; * Possible sarcopenia criteria\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe IKE is a measure of low strength within the cluster of sarcopenic criteria. Its AUC value was higher than that for grip strength and lower than that for the 5TSTS. The cutoff point showing the highest sensitivity and specificity for diagnosing sarcopenia was 12.5 kg or less, with an accuracy higher than grip strength (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e; Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e and Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). Of the total sample, 34.1% (n\u0026thinsp;=\u0026thinsp;29) met this IKE criterion: 62.5% (n\u0026thinsp;=\u0026thinsp;15) of the sarcopenia group, and 20% (n\u0026thinsp;=\u0026thinsp;14) of the non-sarcopenia group (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;.001).\u003c/p\u003e \u003cp\u003eWe then analyzed the AUC of the two recommended sarcopenia strength criteria cluster (grip strength and 5TSTS) and the IKE together (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe present study proposes IKE cutoff points to diagnose sarcopenia in community-dwelling older women. Using 12.5 kg or lower as a cutoff, we assessed whether the IKE is an appropriate tool for measuring strength in women with sarcopenia, in both clinical practice and in research.\u003c/p\u003e \u003cp\u003eThe EWGSOP2 recommends using grip strength and 5TSTS as the strength tests for diagnosing sarcopenia but clarifies that isometric torque methods can be used when grip strength is not possible,[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e] and it could even be a suitable screening tool for sarcopenia in people who have difficulty in walking.[\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e] Both grip strength and IKE appear to be very sensitive for detecting functionally relevant muscle weakness in older adults. Grip strength is probably most appropriate for monitoring the efficacy of treatments in sedentary populations. However, exercise interventions should be monitored with appropriate regional measures.[\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e] In addition, in patients affected by common types of arthritis, grip strength may not be strongly correlated with overall muscle function. Given that these conditions have a relatively high prevalence in the older population, it is of interest to have data that enable the selection of the most appropriate measurements according to the characteristics of the women.[\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eAlthough to our knowledge, there are no published studies proposing a cutoff for IKE as a possible criterion for sarcopenia, research on the topic is increasing. For example, one study in Thailand studied the reduction in IKE over time in older adults and correlated its values with sarcopenia criteria,[\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e] while other authors have used different assessments of knee strength.[\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e, \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e] These studies also obtained AUCs of over 0.70, confirming that the quantification of lower limb strength could be a possible criterion for sarcopenia.\u003c/p\u003e \u003cp\u003eThe sensitivity of grip strength based on the data obtained in our study was 23% less sensitive than IKE. These results are consistent with other studies supporting the suitability of IKE for assessing lower limb strength.[\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e] At their onset, functional limitations may be caused by a considerable decrease in the strength of the lower limbs, which is greater than the drop in handgrip strength. Indeed, the estimated reduction in quadriceps strength linked to ageing is 48%, compared to 23% for grip strength.[\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e] This reflects the differential age-related loss in strength according to muscle group. When using handgrip strength to assess potential strength loss, we may be underestimating the early loss of strength that actually occurs in the quadriceps.[\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eThe importance of assessing performance using IKE has been reported and could be particularly useful in those at high risk of functional decline.[\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e] The IKE has been shown to have the highest predictive value against grip strength in assisted living facilities;[\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e] however, people in these settings are often approaching or in the early stages of functional limitations. The use of IKE should be considered at the initial stages of sarcopenia, where early detection is essential,[\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e] and it is indicated if the person is unable to perform a dynamic squat test(to obtain a general indication of dynamic posture), [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e] which is necessary for tests like the 5TSTS. Given the direct involvement of the knee extensor muscles for actions such as walking or getting up from a chair, its correlation with functional performance in tests such as the 6 m and Time Up and Go (TUG) should not be surprising.[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]\u003c/p\u003e \u003cp\u003eWe observed significant correlations between IKE and performance tests (SPPB and gait speed). Buend\u0026iacute;a-Romero et al. [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e] reported a similar relationship with the TUG and 6-m gait speed tests. Taken together, the data confirm the close relationship between IKE and functional performance.\u003c/p\u003e \u003cp\u003eThe diagnostic accuracy of the IKE relative to other sarcopenia criteria, whether individually or in clusters, was high in our sample, yielding better values than grip strength as a criterion for low strength in both sarcopenia and severe sarcopenia. The criterion of low muscle strength is associated with higher mortality and worse health outcomes,[\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e] so detecting older people at risk is critical for implementing early prevention measures. Assessing IKE with an isokinetic dynamometer is more expensive than using a handheld device (e.g. JAMAR, Smedley). However, its high accuracy [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e] makes it a useful option in cases where the assessment of other low-strength criteria is difficult. It shows better accuracy than grip strength, both as an isolated criterion or in combination with other measures; it can be used in people with walking difficulties; and it is relatively quick to perform, taking only about 5 min/participant.\u003c/p\u003e\n\u003ch3\u003eLimitations\u003c/h3\u003e\n\u003cp\u003eOur study is not without its limitations. The first is that the analysis was conducted only in women in a community setting. The sarcopenia criteria used were those in the EWGSOP2, so the results using other sarcopenia criteria could be different. Drugs that can affect muscle function, such as statins or psychotropic medication, were also not analyzed.\u003c/p\u003e \u003cp\u003eEven though the results obtained are a step forward, there is a need for further studies to identify the best diagnostic tools in both sexes as well as in different settings, and to assess the impact of associated comorbidity and the use of drugs, especially those that could have undesirable adverse effects, such as an increase in muscle weakness.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eThe IKE could be a suitable measure of strength in both clinical practice and research settings in patients with sarcopenia, particularly where other strength parameters cannot be assessed or in people with walking difficulties. The cutoff of \u0026le;\u0026thinsp;12.5 kg has acceptable diagnostic accuracy for older women in the community setting. Further studies in different sexes and settings are needed.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cdiv class=\"DefinitionList\"\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eAUC\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003earea under the curve\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eEWGSOP1\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003e European Working Group on Sarcopenia in Older People guidelines 1\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eEWGSOP2\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003e European Working Group on Sarcopenia in Older People guidelines 2\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eIKE\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eIsometric knee extension\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003ePPV\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003ePositive predictive value\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eROC\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eReceiver operating characteristics\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eSPPB\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eShort Physical Performance Battery\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003eSMMI\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eSkeletal muscle mass index\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv class=\"DefinitionListEntry\"\u003e \u003cdiv class=\"Term\"\u003e5TSTS\u003c/div\u003e \u003cdiv class=\"Description\"\u003e \u003cp\u003eThe 5 times sit-to-stand\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003c/div\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eethics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe study was conducted according to the guidelines of the Declaration of Helsinki and approved by the Ethics Committee for Human Research of the University of Valencia (protocol code 1534298 \u0026nbsp;approved 14 January 2021). Following a briefing about the study and its aims, all participants signed informed consent as a precondition for taking part.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis work was supported by Conselleria de Innovaci\u0026oacute;n, Universidades, Ciencia y Sociedad digital, Valencia, Spain [Grant number GV/2020/071].\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eSponsor has no role in the design, methods, subject recruitment, data collections, analysis and preparation of paper.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026rsquo; contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eStudy concept and design: OC, FMMA; Acquisition of data: PPR, JBI, AP, RFV, FMM; Analysis and interpretation of data: PPR, JBI, AP, RFV, FMM; Drafting of the manuscript: PPR, JBI, AP, RFV, FMM; Critical revision of the manuscript for important intellectual content: OC, FMMA\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe are grateful to all of the participants, as well as the primary healthcare centers and social centers that participated in the recruitment.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eCruz-Jentoft AJ, Baeyens JP, Bauer JM, Boirie Y, Cederholm T, Landi F, et al. Sarcopenia: European consensus on definition and diagnosis: Report of the European Working Group on Sarcopenia in Older People. Age Ageing. 2010;39:412\u0026ndash;23.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePetermann-Rocha F, Balntzi V, Gray SR, Lara J, Ho FK, Pell JP, et al. Global prevalence of sarcopenia and severe sarcopenia: a systematic review and meta-analysis. J Cachexia Sarcopenia Muscle. 2022;13:86\u0026ndash;99.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCruz-Jentoft AJ, Bahat G, Bauer J, Boirie Y, Bruy\u0026egrave;re O, Cederholm T, et al. Sarcopenia: revised European consensus on definition and diagnosis. Age Ageing. 2019;48:16\u0026ndash;31.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCruz-Jentoft AJ, Sayer AA, Sarcopenia. Lancet Lond Engl. 2019;393:2636\u0026ndash;46.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNacul LC, Mudie K, Kingdon CC, Clark TG, Lacerda EM. Hand grip strength as a clinical biomarker for ME/CFS and disease severity. Front Neurol. 2018;9.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNorman K, Stob\u0026auml;us N, Smoliner C, Zocher D, Scheufele R, Valentini L, et al. Determinants of hand grip strength, knee extension strength and functional status in cancer patients. Clin Nutr Edinb Scotl. 2010;29:586\u0026ndash;91.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBagis S, Sahin G, Yapici Y, Cimen OB, Erdogan C. The effect of hand osteoarthritis on grip and pinch strength and hand function in postmenopausal women. Clin Rheumatol. 2003;22:420\u0026ndash;4.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDedeoğlu M, Gafuroğlu \u0026Uuml;, Yilmaz \u0026Ouml;, Bodur H. The relationship between hand hrip and pinch strengths and disease activity, articular damage, pain, and disability in patients with rheumatoid arthritis. Arch Rheumatol. 2013;28:069\u0026ndash;77.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHuang C, Niu K, Kobayashi Y, Guan L, Momma H, Cui Y, et al. An inverted J-shaped association of serum uric acid with muscle strength among Japanese adult men: a cross-sectional study. BMC Musculoskelet Disord. 2013;14:258.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKemmler W, Teschler M, Goisser S, Bebenek M, von Stengel S, Bollheimer LC, et al. Prevalence of sarcopenia in Germany and the corresponding effect of osteoarthritis in females 70 years and older living in the community: results of the FORMoSA study. Clin Interv Aging. 2015;10:1565\u0026ndash;73.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGuralnik JM, Simonsick EM, Ferrucci L, Glynn RJ, Berkman LF, Blazer DG, et al. A short physical performance battery assessing lower extremity function: association with self-reported disability and prediction of mortality and nursing home admission. J Gerontol. 1994;49:M85\u0026ndash;94.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAndrews AW, Thomas MW, Bohannon RW. Normative values for isometric muscle force measurements obtained with hand-held dynamometers. Phys Ther. 1996;76:248\u0026ndash;59.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eArnold CM, Warkentin KD, Chilibeck PD, Magnus CRA. The reliability and validity of handheld dynamometry for the measurement of lower-extremity muscle strength in older adults. J Strength Cond Res. 2010;24:815\u0026ndash;24.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBuend\u0026iacute;a-Romero \u0026Aacute;, Hern\u0026aacute;ndez-Belmonte A, Mart\u0026iacute;nez-Cava A, Garc\u0026iacute;a-Conesa S, Franco-L\u0026oacute;pez F, Conesa-Ros E, et al. Isometric knee extension test: A practical, repeatable, and suitable tool for lower-limb screening among institutionalized older adults. Exp Gerontol. 2021;155:111575.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSalamone IM, Quattrocelli M, Barefield DY, Page PG, Tahtah I, Hadhazy M, et al. Intermittent glucocorticoid treatment enhances skeletal muscle performance through sexually dimorphic mechanisms. J Clin Invest. 2022;132:e149828.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCostanzo L, De Vincentis A, Di Iorio A, arnol S, Ferrucci L, Antonelli Incalzi R, et al. Impact of low muscle mass and low muscle strength according to EWGSOP2 and EWGSOP1 in community-dwelling older people. J Gerontol Ser A. 2020;75:1324\u0026ndash;30.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMalmstrom TK, Miller DK, Simonsick EM, Ferrucci L, Morley JE. SARC-F: a symptom score to predict persons with sarcopenia at risk for poor functional outcomes. J Cachexia Sarcopenia Muscle. 2016;7:28\u0026ndash;36.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRoberts HC, Denison HJ, Martin HJ, Patel HP, Syddall H, Cooper C, et al. A review of the measurement of grip strength in clinical and epidemiological studies: towards a standardised approach. Age Ageing. 2011;40:423\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDodds RM, Syddall HE, Cooper R, Benzeval M, Deary IJ, Dennison EM, et al. Grip strength across the life course: normative data from twelve British studies. PLoS ONE. 2014;9:e113637.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCesari M, Kritchevsky SB, Newman AB, Simonsick EM, Harris TB, Penninx BW, et al. Added value of physical performance measures in predicting adverse health-related events: results from the health, aging and body composition study. J Am Geriatr Soc. 2009;57:251\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBohannon RW. Hand-held dynamometry: A practicable alternative for obtaining objective measures of muscle strength. Isokinet Exerc Sci. 2012;20:301\u0026ndash;15.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFrancis P, Toomey C, Mc Cormack W, Lyons M, Jakeman P. Measurement of maximal isometric torque and muscle quality of the knee extensors and flexors in healthy 50- to 70-year-old women. Clin Physiol Funct Imaging. 2017;37:448\u0026ndash;55.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAssantachai P, Muangpaisan W, Intalapaporn S, Sitthichai K, Udompunturak S. Cut-off points of quadriceps strength, declines and relationships of sarcopenia-related variables among Thai community-dwelling older adults. Geriatr Gerontol Int. 2014;14(Suppl 1):61\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAbdalla PP, Dos Santos Carvalho A, Dos Santos AP, Venturini ACR, Alves TC, Mota J, et al. Cut-off points of knee extension strength allometrically adjusted to identify sarcopenia risk in older adults: A cross-sectional study. Arch Gerontol Geriatr. 2020;89:104100.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCarvalho do Nascimento PR, Bilodeau M, Poitras S. How do we define and measure sarcopenia? A meta-analysis of observational studies. Age Ageing. 2021;50:1906\u0026ndash;13.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLauretani F, Russo CR, Bandinelli S, Bartali B, Cavazzini C, Di Iorio A, et al. Age-associated changes in skeletal muscles and their effect on mobility: an operational diagnosis of sarcopenia. J Appl Physiol. 2003;95:1851\u0026ndash;60.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMartien S, Delecluse C, Boen F, Seghers J, Pelssers J, Van Hoecke A-S, et al. Is knee extension strength a better predictor of functional performance than handgrip strength among older adults in three different settings? Arch Gerontol Geriatr. 2015;60:252\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSamuel D, Wilson K, Martin HJ, Allen R, Sayer AA, Stokes M. Age-associated changes in hand grip and quadriceps muscle strength ratios in healthy adults. Aging Clin Exp Res. 2012;24:245\u0026ndash;50.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eEvans W. Functional and metabolic consequences of sarcopenia. J Nutr. 1997;127(5 Suppl):998S\u0026ndash;1003S.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSpexoto MCB, Ram\u0026iacute;rez PC, de Oliveira M\u0026aacute;ximo R, Steptoe A, de Oliveira C, Alexandre TdaS. European Working Group on Sarcopenia in Older People 2010 (EWGSOP1) and 2019 (EWGSOP2) criteria or slowness: which is the best predictor of mortality risk in older adults? Age Ageing. 2022;51:afac164.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-geriatrics","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bgtc","sideBox":"Learn more about [BMC Geriatrics](http://bmcgeriatr.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bgtc/default.aspx","title":"BMC Geriatrics","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Sarcopenia, older, women, strength, isometric knee extension.","lastPublishedDoi":"10.21203/rs.3.rs-3860792/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3860792/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e \u003cb\u003eBackground.\u003c/b\u003e Muscle strength is one of the most reliable measures used for the identification of sarcopenia. The European Working Group on Sarcopenia in Older People update (EWGSOP2) proposed the use of the Grip Strength and Chair Stand tests, while clarifying that isometric torque methods can be used when performing the Grip Strength test is impossible.\u003c/p\u003e \u003cp\u003eThe aim is to assess isometric knee extension (IKE) strength as a potential criterion for detecting sarcopenia within the assessment of muscle strength, and to propose a cutoff for diagnosis.\u003c/p\u003e \u003cp\u003e \u003cb\u003eMethods.\u003c/b\u003e A cross-sectional study was designed and community-dwelling women aged 70 years and over were included. IKE and sarcopenia criteria (EWGSOP2) were assessed. Skeletal muscle mass was assessed by bioelectrical impedance analysis; muscle mass strength by handgrip; and physical performance by the 5 times sit-to-stand test, the Short Physical Performance Battery, and gait speed. The diagnostic accuracy for each sarcopenia criterion was calculated using sensitivity, specificity, positive and negative predictive value, and the area under the curve (AUC). Cutoff points for sarcopenia from IKE were defined with the ROC curve.\u003c/p\u003e \u003cp\u003e \u003cb\u003eResults.\u003c/b\u003e The sample comprised 94 women with a mean age of 75.9 years (standard deviation 5.6, range 70\u0026ndash;92), of whom 25.5% (n\u0026thinsp;=\u0026thinsp;24) met criteria for sarcopenia\u0026mdash;mainly severe sarcopenia (73.8%, n\u0026thinsp;=\u0026thinsp;17). Correlations were observed between IKE and each individually analyzed sarcopenia criterion except skeletal muscle mass, with AUC values exceeding 0.70 in all cases. The IKE cutoff showing the highest accuracy for the diagnosis of sarcopenia was 12.5 kg or less (AUC 0.76, 95% confidence interval [CI] 0.64\u0026ndash;0.88; sensitivity: 65.2%, 95% CI 45.7\u0026ndash;84.7; specificity 77.4%, 95% CI 60.3\u0026ndash;94.5; positive predictive value 62.5%, 95 CI% 42.7\u0026ndash;82.3; negative predictive value 88.8%, 95% CI 75.9\u0026ndash;100).\u003c/p\u003e \u003cp\u003e \u003cb\u003eConclusions.\u003c/b\u003e IKE could be a suitable tool for measuring muscular strength in sarcopenia when other strength parameters cannot be assessed or in people with walking difficulties.\u003c/p\u003e","manuscriptTitle":"Diagnostic accuracy of isometric knee extension strength as a sarcopenia criteria in community-dwelling older women","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-01-22 15:36:38","doi":"10.21203/rs.3.rs-3860792/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-10-20T21:10:43+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-10-18T21:53:26+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"91941788413505906326219592487649386636","date":"2024-10-04T15:01:52+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-09-21T11:38:32+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"65679613866799249854675247883057171021","date":"2024-09-16T17:47:08+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"08d7ebe4-2bcc-4f85-9aa0-07708ca25f76","date":"2024-05-07T07:00:32+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"88820529-6666-4088-8bf5-8873b08a885d","date":"2024-05-02T07:35:55+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-04-25T16:40:54+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-04-25T05:56:55+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2024-01-19T05:11:52+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-01-19T05:10:05+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Geriatrics","date":"2024-01-13T17:10:55+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-geriatrics","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bgtc","sideBox":"Learn more about [BMC Geriatrics](http://bmcgeriatr.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bgtc/default.aspx","title":"BMC Geriatrics","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"f2ef82ff-c68d-4273-889b-961e4747ead1","owner":[],"postedDate":"January 22nd, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2024-12-09T16:04:35+00:00","versionOfRecord":{"articleIdentity":"rs-3860792","link":"https://doi.org/10.1186/s12877-024-05569-y","journal":{"identity":"bmc-geriatrics","isVorOnly":false,"title":"BMC Geriatrics"},"publishedOn":"2024-12-02 15:57:53","publishedOnDateReadable":"December 2nd, 2024"},"versionCreatedAt":"2024-01-22 15:36:38","video":"","vorDoi":"10.1186/s12877-024-05569-y","vorDoiUrl":"https://doi.org/10.1186/s12877-024-05569-y","workflowStages":[]},"version":"v1","identity":"rs-3860792","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3860792","identity":"rs-3860792","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}