High body mass index linked to poor response in infliximab

Rheumatoid arthritis (RA) patients with a high body mass index (BMI) respond less well to infliximab (Remicade, Centocor Inc.), according to a new study published in Arthritis & Rheumatism.

Even when researchers adjusted for disease activity and anti-citrullinated protein antibody status, patients with a high BMI exhibited a “diminished clinical response to infliximab treatment,” the study’s authors reported.

Ruth Klaasen, MD, from the University of Amsterdam in the Netherlands, and other researchers assessed the Disease Activity Score in 28 joints (DAS28) in 89 patients with active RA. The researchers found a positive correlation between BMI and DAS28 at baseline. After correcting for baseline DAS28 with an analysis of covariance, the researchers found a significant negative association between BMI and the absolute decrease in DAS28 (P=.001) after 16 weeks, when adjusted for anti-citrullinated protein antibodies.

“Although the infliximab dosage is based on body weight, RA patients with a high BMI responded less well to infliximab. This finding suggests that adipose tissue could play a role in the pathophysiology of RA,” the researchers wrote.