Predictive correlates of arthritis and joint damage in systemic lupus erythematosus: a multinational prospective cohort study

Abstract Objectives To determine the prevalence and predictive correlates of arthritis and joint damage in systemic lupus erythematosus (SLE) patients in the Asia-Pacific Lupus Collaboration (APLC) cohort, and to determine their impact on health-related quality of life (HRQoL). Methods SLE patient data (2013–2020) were collected from the prospective multinational APLC cohort. We defined arthritis according to the SLE Disease Assessment Index (SLEDAI-2K) definition of persistent arthritis as arthritis in ≥2 consecutive visits, and joint damage according to the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI) definition (deforming or erosive arthritis). HRQoL was measured by Short Form Survey (SF36). Descriptive statistics, univariable and multivariable Cox hazard models, and Kaplan–Meier analyses were performed. Results During median 2.5 (1.0–5.1) years of follow-up, 803/4106 (19.6%) patients had arthritis at least once, and 18/3383 (0.53%) accrued joint damage. Patients with arthritis were more likely to be female, Caucasian, current smokers at enrolment, and less like to have tertiary education; they also had higher overall disease activity, and lower physical and mental HRQoL. Kaplan–Meier analysis demonstrated that joint damage was more likely in patients with arthritis. Persistent arthritis and longer follow-up were risk factors for joint damage accrual; being from high-income countries was protective. Patients with joint damage also had worse physical HRQoL. Conclusion Arthritis in the APLC cohort was infrequent compared with other cohorts and was associated with smoking, higher overall disease activity, and damage accrual across multiple domains. Presence of arthritis significantly impacted physical and mental HRQoL. Joint damage was strongly predicted by persistent arthritis.