The Problem of Pain in Lupus: Epidemiological Profiles of Patients Attending Multidisciplinary Pain Clinics.

This was a descriptive, cross-sectional study of electronic health records (EHR) derived from the Stanford Medicine Research Data Repository (STARR) ( Callahan et al., 2023 ). We retrospectively queried EHR to identify adult (≥18 years) patients who had: 1) Established care (defined here as at least two visits between 1998 and 2023) at outpatient rheumatology clinics (including a joint immunology-dermatology clinic) at a single academic medical center in Northern California; 2) two or more SLE ICD-9 and ICD-10 codes (ICD-9 code of 710.0 and ICD-10 codes under M32, excluding M32.0 for drug-induced SLE); and 3) received an SLE ICD-9 or ICD-10 code after October 29, 2013, the earliest date of diagnosis for a patient to enter the pain clinics. Our case definition of SLE has been validated and used extensively ( Arkema et al., 2016 ). We obtained sex, age, race, ethnicity, insurance status, marital status, and body mass index (BMI) variables from the EHR. Race and ethnicity were determined based on selecting from a fixed set of categories, as was marital status. Insurance status was characterized as public, private, or other. The Area Deprivation Index (ADI) uses 17 socioeconomic indicators (such as poverty, housing-quality, and employment measures) across census tract, zip code, and county levels and captures socioeconomic health outcome disparities( Kind & Buckingham, 2018 ). Each 9-digit zip code is associated with a raw ADI score that is then ranked against other zip codes. For this analysis, we used state-wide decile rankings and grouped them into strata of two deciles such that strata 1 was made up of the highest two deciles (1st and 2nd) up to strata 5, which was made up of the lowest deciles (9th and 10th). Mental health diagnoses, pain codes, COPCs and comorbidities were determined based on ICD-9 and ICD-10 codes extracted from the EHR. The Functional Comorbidity Index (FCI) code was derived from Sears and Rundell 2020 ( Sears & Rundell, 2020 ). We calculated descriptive statistics (means, standard deviations, ranges, frequencies, and percentages) for relevant variables. We compared those who had at least one visit to the pain clinics against those who did not have any visits to the pain clinics. We conducted between-group comparisons for continuous variables such as age, BMI, and total count of comorbidities using t-tests. For categorical variables, we used chi-square tests or Fischer’s exact test if data were sparse.

A majority of the sample (n=1319), 90.8% were female, and the mean age was 48.8 years ± 19.8 ( Table 1 ). Half the patients were White (49.8%), 22.7% were Asian, and 4.6% were Black. Approximately 20% were Hispanic or Latino. Almost half (49.1%) were married or had a life partner; 40% were single. Most patients reported having private insurance (57.3%), and 35% received public insurance. Most patients were from the highest socioeconomic levels in California, as 59.4% of the study sample resided in the state’s two most socioeconomically advantaged deciles. Approximately 44% of the sample had a mental health condition. Most patients (60.8%) had COPCs. The most prevalent COPC was chronic low back pain (36.6%), followed closely by fibromyalgia (30.7%). We identified among them the sample of patients who were seen at least once, and thus received medical evaluation with possible follow-up, at the tertiary pain management centers (n=77, 5.8%). There was a comparable proportion of female patients seen at the pain clinics (94.8%, n=77) compared with those not seen at the pain clinics (90.6%, n=1242). Pain clinic patients were older, mean age of 54.1 vs. 48.4 years in non-pain clinic patients). A larger percentage of pain clinic patients were on public insurance: 50.7% vs. 34.2% in non-pain clinic patients. Pain clinic patients had a higher mean BMI, 28.0 vs. 26.1 in non-pain clinic patients. The two populations were also similar concerning the distribution of marital status and socioeconomic status as measured by ADI. Patients referred to pain clinics were less likely to be Asian (14.3% vs 23.2% among non-pain clinic attendees). Pain clinic patients had nearly double (76.7%) the proportion of mental health conditions compared with non-pain clinic patients (42.4%). Pain clinic patients had a statistically significant higher prevalence of each COPC than non-pain clinic patients. Patients with SLE seen at pain clinics had statistically significant higher prevalences of almost all comorbidities (FCI score mean of 6.0, compared to an FCI mean of 2.9 in patients with SLE who weren’t seen in pain clinics), excluding osteoporosis, congestive heart failure/heart disease, and peripheral vascular disease. All 18 comorbidities measured by the FCI were more frequently seen in pain clinic patients compared to non-pain clinic patients.

In the United States, there are more than 200,000 people living with systemic lupus erythematosus (SLE), a chronic inflammatory rheumatic disease with multi-organ involvement that disproportionately affects females and racial minorities (Lupus, 2022). Living with a chronic disease such as SLE confers multiple challenges. Pain is a frequent self-reported symptom in SLE and is often one of the first symptoms of the disease ( Chan et al., 2008 ). Pain takes many forms in SLE: musculoskeletal, headache, abdominal pain, pleuritis, secondary fibromyalgia and Raynaud’s phenomenon ( Pisetsky et al., 2021 ). Despite treatment advances, pain remains the most prominent, unaddressed patient complaint in SLE ( Falasinnu et al., 2021 ). More than half of patients with SLE have a concomitant diagnosis of chronic overlapping pain conditions (COPC) ( Falasinnu et al., 2022 ), thus compounding their disease burden and its impact. Thus, comprehensive pain care from pain clinics may better address the multifactorial nature of pain ( May et al., 2018 ). Our aim is to describe the sociodemographic and clinical characteristics of chronic pain patients with SLE presenting to tertiary pain clinics, with a focus on biopsychosocial and socioeconomic characteristics. Such insight is important for healthcare professionals, including pain management nurses, in tailoring effective interventions and personalized care strategies. Findings will contribute to the understanding of SLE-related pain and will also inform clinical practice, guiding healthcare providers in delivering more precise and patient-centered pain management strategies for individuals living with the complex interplay of SLE and chronic pain.

Understanding the epidemiology of patients with SLE who attend pain clinics can contribute to improving patient care, refining treatment strategies, optimizing resource allocation, and guiding future research and policy directions. We observed key differences in patients with SLE who were referred to tertiary pain clinics compared to those who were not. Those evaluated at the pain clinics tended to be older, were more likely to be on public health insurance, and had a lower proportion of Asian patients and a higher proportion of Black patients, compared to non-pain clinic patients. Almost all pain clinic patients had a COPC and were more likely to have depression, anxiety, mood, or substance/alcohol use disorders. In addition, pain clinic patients had higher prevalences of comorbidities. These findings suggest that patients referred to the pain clinic are a more complex subset of individuals and that their care should include managing concurrent debilitating conditions. This is consistent with other studies of chronic pain in SLE and in other disease states where individuals with concomitant diagnoses have higher rates of anxiety and depression disorders and more comorbidities ( Mailis-Gagnon et al., 2007 ; Waldheim et al., 2013 ). This work adds to this body of knowledge by characterizing the population of patients with SLE at multidisciplinary pain clinics, highlighting their distinct clinical profiles and management needs. Patients living with pain and depression have worse outcomes and higher healthcare costs than do patients with only one or the other condition ( Rayner et al., 2016 ; Wu et al., 2022 ). Thus, understanding the specific needs and care complexities of pain patients with SLE with psychiatric comorbidities is essential to providing targeted care to this vulnerable patient population, e.g., social worker evaluations in addition to pain clinic evaluations ( Carstensen et al., 2012 ). Some limitations to our study were that the study population was conducted at a single tertiary care hospital system and is disproportionately composed of high socioeconomic classes, limiting the generalizability of our findings to the general population with SLE. There may be limitations in using race/ethnicity from EHR including potential inaccuracies due to reliance on patient self-reporting or healthcare provider categorization, which may not fully capture the complexity and nuances of individual racial and ethnic identities. Our study has notable strengths. This is the first descriptive study on patients with SLE who were treated at pain clinics compared with those who were not. We were able to capture both demographic and diagnostic data. Altogether, we present an extensive picture of the patient population with SLE and chronic pain. Our study highlights the complexity of pain in patients with SLE and underscores the need for multidisciplinary pain management in rheumatic disease. Clinical care should aggressively leverage resources to help manage the complex comorbidities in this patient population.

Recognizing the patterns and frequencies of pain presentations among patients with SLE can help to refine therapeutic strategies and improve patient outcomes. Pain clinics and other medical institutions can benefit from such data to allocate resources more effectively, ensuring that patients with SLE receive the necessary attention and support.

The treatment of SLE is complex, and pain management is a critical aspect of patient care. These findings have profound implications for nursing education, practice, and research in the field of pain management. This research offers an opportunity to enhance the curriculum in nursing schools by incorporating a deeper understanding of the unique pain experiences and epidemiological characteristics of patients with SLE. By integrating this knowledge, nursing students can better prepare for providing empathetic and tailored care to patients with SLE seeking pain management. In addition, this research could guide the development of patient-centered care plans that address the distinct needs of this population. Clinicians could adapt the insights gained from this research to refine their assessment techniques, intervention strategies, and patient education initiatives, ultimately improving the overall care experience for lupus patients dealing with chronic pain. Future studies can build upon the epidemiological profiles identified in this research to delve deeper into the mechanisms underlying SLE-related pain and explore innovative interventions. Additionally, the findings underscore the importance of interdisciplinary collaboration in pain management, encouraging researchers to collaborate across specialties to develop holistic approaches that address both the disease-specific aspects of SLE and the unique pain challenges it presents.