Smoking, but not use of complementary and alternative medicine predicts residual functional disability in patients with inflammatory arthritis on biologic disease-modifying anti-rheumatic drugs: Results from the Singapore National Biologics Register.

CAM use was not associated with high mHAQ at 6 months. Smoking was an independent predictor of residual functional disability at 6 months, even after adjusting for age, comorbidity and baseline mHAQ. Greater emphasis on smoking cessation may improve long-term functional outcomes in IA patients on bDMARDs.