Comparative effectiveness of biologics in patients with rheumatoid arthritis stratified by body mass index and sex: a cohort study in SCQM

BackgroundObesity is associated with lower treatment response in patients with rheumatoid arthritis (RA). Among obese patients, abatacept was suggested as a preferable option to tumour necrosis factor alpha (TNF) inhibitors. Sex and gender differences in RA were described. ObjectivesTo assess the comparative effectiveness of etanercept, infliximab, and abatacept, compared to adalimumab, in patients with RA stratified by body mass index (BMI) and sex. MethodsObservational cohort study in the Swiss Clinical Quality Management in Rheumatic Diseases (SCQM) registry (1997-2019). RA patients were classified in BMI-based cohorts: obese, overweight, and normal weight. Each BMI cohort was studied overall and stratified by sex. The study outcome was remission within 12-months, defined as a disease activity score (DAS28) <2.6. Missingness was addressed using confounder-adjusted response rate with attrition correction (CARRAC). Logistic regression compared the effectiveness of etanercept, infliximab, and abatacept versus adalimumab. ResultsThe study included 443 obese, 829 overweight, and 1243 normal weight RA patients. Across the BMI cohorts, there were no significant differences in the odds of remission at [&le;]12-months for the study drugs compared to adalimumab. However, among females, an inverse effect for infliximab was found, whereby overweight patients had higher odds of remission, while obese patients had lower odds of remission, compared to the respective adalimumab users. ConclusionsDespite the previous hypothesis, treatment with abatacept showed similar odds of remission compared to adalimumab in all BMI cohorts. Conversely, compared to adalimumab, infliximab performed better in overweight female patients but worse in female patients with obesity. However, further validation is needed.