Higher BMI Associated With Reduced Likelihood of Minimal Disease Activity in Psoriatic Arthritis

Higher BMI Associated With Reduced PsA Disease Control

• A longitudinal cohort study included 1291 patients with psoriatic arthritis (mean age, 44.7 years; 56% male; mean BMI, 28.8 kg/m²) from the Gladman Krembil PsA Program.
• Higher BMI was independently associated with lower odds of minimal disease activity (MDA; OR, 0.97; 95% CI, 0.94-0.99) and negatively associated with all MDA components except swollen joint count.
• The association was strongest with TNF inhibitors excluding infliximab (OR, 0.94; 95% CI, 0.92-0.97); no significant association occurred with IL-17, IL-12/23, IL-23, or Janus kinase inhibitors.

Higher body mass index (BMI) was independently associated with lower odds of achieving minimal disease activity (MDA) in patients with psoriatic arthritis (PsA), with the strongest effect observed among patients treated with tumor necrosis factor-α inhibitors (TNFi), according to findings from a longitudinal cohort study.

Investigators analyzed data from 1291 patients enrolled in the Gladman Krembil PsA Program who had longitudinal BMI measurements available during follow-up. Associations between BMI and MDA were evaluated using generalized estimating equations and linear mixed models, with analyses adjusted for demographic and clinical factors, including treatment class, smoking, fibromyalgia, radiographic damage, and anxiety or depression.

The cohort had a mean age of 44.7 years, 56% of participants were male, and the mean BMI was 28.8 kg/m².

In multivariable analyses, increasing BMI was independently associated with a lower likelihood of achieving MDA (odds ratio [OR], 0.97; 95% CI, 0.94-0.99). Female sex, older age, smoking, fibromyalgia, and radiographic damage were also independently associated with reduced odds of reaching MDA.

Higher BMI was negatively associated with nearly every component of MDA, with the exception of swollen joint count, suggesting that excess body weight primarily influenced subjective measures of disease activity.

Subgroup analyses demonstrated that BMI had the greatest impact among patients receiving TNFi therapy. Higher BMI at treatment initiation was associated with significantly lower odds of achieving MDA in patients treated with TNFi, excluding infliximab (OR, 0.94; 95% CI, 0.92-0.97). Similar findings were observed when BMI was assessed longitudinally. In contrast, no significant association was identified among patients treated with IL-17, IL-12/23, or IL-23 inhibitors or Janus kinase inhibitors.

The authors concluded that “high BMI decreases the odds for MDA in PsA, mainly affecting subjective disease measures.” They further noted that “this effect is most pronounced in patients treated with TNFi (except infliximab).”

Reference
Mehta P, Yang M, Kharouf F, et al. Body mass index and achievement of minimal disease activity in psoriatic arthritis across different classes of advanced therapy. Rheumatology (Oxford). 2026;65(7):keag303. doi:10.1093/rheumatology/keag303