Few data exist on the association between increased BMI and response to conventional synthetic disease-modifying anti-rheumatic drugs (csDMARDs) in rheumatoid arthritis (RA).We aimed to explore the association between increased (overweight or obese) BMI on csDMARD-prescribing, methotrexate-dose and disease activity over 12-months.Participants in an international RA database were stratified into early (<1year post-diagnosis) and established RA. EULAR response, DAS28 remission and treatments were recorded at baseline, 6-months and 12-months. Increased BMI was explored in early and established RA, as predictors of good EULAR response, DAS28 remission, number of csDMARDs and methotrexate-dose, using logistic and linear regression.Data from 1313 patients, 44.3% with early RA, were examined. In early RA, increased BMI was not significantly associated with remission. In established RA, obese patients on monotherapy were significantly less likely to achieve good EULAR response or DAS28 remission at 6 months and more likely to be treated with combination csDMARDs, compared with normal BMI. In patients taking methotrexate, overweight and obese patients with early and established RA were exposed to higher methotrexate doses (mono- and combination-therapy), with a mean dose of 20mg/week, compared to 15mg/week in those of normal BMI.We observed, compared to patients with normal BMI, overweight and obese individuals experienced more intensive csDMARD exposures. Similar response rates were observed in early RA but increased BMI was associated with reduced response in established RA. Optimisation of targeted RA treatment remains important, particularly in those with increased BMI where response in established disease may be attenuated.
Mrinalini Dey, Sizheng S Zhao, Robert J Moots, Sytske Anne Bergstra, Robert B Landewe, Nicola J Goodson