Life Events, Caregiving, and Risk of Autoimmune Rheumatic Diseases in the Women's Health Initiative Observational Study.

Objective: Growing evidence suggests psychosocial stressors may increase risk of developing autoimmune disease. We examined stressful life events and caregiving in relation to incident rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) in the Women's Health Initiative Observational Study cohort.

Methods: The sample of postmenopausal women included 211 incident RA or SLE cases reported within 3 years after enrollment, confirmed by use of disease-modifying antirheumatic drugs (i.e., probable RA/SLE), and 76,648 noncases. Baseline questionnaires asked about life events in the past year, caregiving, and social support. We used Cox regression models to calculate hazard ratios (HR) and 95% confidence intervals (95% CIs), adjusting for age, race/ethnicity, occupational class, education, pack-years of smoking and BMI.

Results: Incident RA/SLE was associated with reporting 3 or more life events (e.g., age-adjusted HR 1.70 [95% CI 1.14, 2.53]; P for trend = 0.0026). Elevated HRs were noted for physical (HR 2.48 [95% CI 1.02, 6.04]) and verbal (HR 1.34 [0.89, 2.02]) abuse (P for trend = 0.0614), 2 or more interpersonal events (HR 1.23 [95% CI 0.87, 1.73]; P for trend = 0.2403), financial stress (HR 1.22 [95% CI 0.90, 1.64]), and caregiving 3 or more days per week (HR 1.25 [95% CI 0.87, 1.81]; P for trend = 0.2571). Results were similar, excluding women with baseline symptoms of depression or moderate-to-severe joint pain in the absence of diagnosed arthritis.

Conclusion: Our findings support the idea that diverse stressors may increase risk of developing probable RA or SLE in postmenopausal women, supporting the need for further studies in autoimmune rheumatic diseases, including childhood adverse events, life event trajectories, and modifying psychosocial and socioeconomic factors.