Self-reported stress and rheumatoid arthritis in older European adults

Abstract Background Stress can increase the risk of development of various autoimmune diseases, including rheumatoid arthritis (RA). The rising prevalence of RA highlights the need to understand its predictors. We investigated the relationship between self-perceived stress and RA occurrence, overall and across sexes, given that females report higher stress and RA prevalence. Methods Longitudinal sample (n = 36,295; 56% female; mean age 66 years) was created using the Survey of Health, Ageing, and Retirement in Europe. Self-reported stress period and its timing were assessed in wave 7, forming the variable “proportion of life in stress”. Occurrence of RA was tracked over 4 years, in waves 8 & 9. Mixed-effects logistic regression models linked life stress proportion to RA occurrence (overall and stratified by sex). Among those who reported stress, we modeled the interaction between the proportion of life in stress and its start: early (<31y), mid (31-55y), and later (>55y) life. We adjusted for baseline sex, marital status, education, childhood socioeconomic status, and time-varying age, chronic conditions and body mass index, including respondent and country random intercepts. Results Females reported a higher proportion of life in stress than males (mean 7.4y (SD 12.7y) vs 5.6y (11.1y)). For both sexes, each 10% increase of life in stress was associated with a 7% higher odds of RA occurrence (OR 1.07; 95% CI 1.03,1.11). The highest magnitude of the stress-RA association was observed in females experiencing late-life stress (OR 1.21; 95% CI: 1.01,1.46) and in males experiencing mid-life stress (OR 1.17; 95% CI: 1.01,1.37) when compared to early-life stress. Conclusions Among older Europeans, a higher proportion of life in stress was associated with increased odds of developing RA. However, the critical period of stress differed by sex. These findings underscore the importance of considering both the amount and timing of stress in RA risk assessment. Key messages • Longer proportion of life in stress was tied to an increased RA occurrence in older European adults, followed for 4 years. • Stress-RA link did not vary by sex but critical stress periods differed by sex.