Prevalence and Risk Factors of Substance Use Disorder in Rheumatoid Arthritis.

Objective: In this study, we aimed to determine the lifetime prevalence of substance use disorder (SUD) in a Canadian rheumatoid arthritis (RA) cohort and factors associated with SUD in RA.

Methods: Participants with RA (N = 154) were recruited via rheumatology clinics as part of a larger cohort study of psychiatric comorbidity in immune-mediated inflammatory diseases. SUD is defined as the uncontrolled use of a substance despite the harmful consequences of its use. To identify lifetime SUD, the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition was administered to participants. Participants' sociodemographic and RA clinical characteristics were also assessed. We examined factors associated with lifetime SUD using unadjusted and adjusted logistic regression modeling.

Results: Twenty-three (14.9%) of 154 participants with RA met the criteria for a lifetime diagnosis of SUD. The majority of the participants were women, were White, had postsecondary education, and were on a disease-modifying antirheumatic drug. Factors associated with increased odds of SUD were male sex (adjusted odds ratio [aOR]: 3.63, 95% confidence interval [CI]: 1.03-12.73), younger age (aOR: 0.94, 95% CI: 0.90-0.98), and ever smoking (aOR: 6.44, 95% CI: 1.53-27.07).

Conclusion: We found that approximately 1 in 7 individuals with RA had a lifetime diagnosis of SUD, highlighting the importance of identifying and treating SUD in those with RA. In particular, the following factors were associated with higher odds of SUD: male sex, younger age, and smoking behaviors.