TUMOR necrosis factor inhibitor (TNFi) therapy in patients with psoriatic arthritis (PsA) does not appear to accelerate weight gain beyond expected age-related trends, according to findings from a retrospective cohort study.
Evaluating Weight Changes Before and After TNF Inhibition
Researchers analyzed 234 adults with PsA who had at least two recorded weight measurements before and after starting TNFi treatment. The cohort had a mean age of 41.8 years, and most participants were male. Over an average follow-up period of nearly 8 years, mean body weight increased modestly from 83.8 kg before treatment to 86.4 kg during therapy, a difference that was not statistically significant.
The rate of weight gain also slowed slightly following TNFi initiation. Before treatment, patients gained an average of 0.52 kg per year compared with 0.28 kg after treatment, suggesting a mild reduction in the pace of weight gain. These findings remained consistent after adjusting for age, sex, and disease duration.
Interpreting the Findings in Clinical Context
These results contrast with earlier observations suggesting TNF inhibition contributes to increased body weight in psoriatic disease. By adjusting for natural weight gain that occurs with age, this study offers a more refined perspective on treatment effects. The findings support that TNFi therapy may help stabilize metabolic trends rather than exacerbate them, which could be particularly relevant for patients already managing obesity or metabolic syndrome.
Implications for Managing Psoriatic Arthritis and Weight
While prior studies have reported weight gain with TNF inhibitors in psoriatic disease, this analysis accounted for natural changes in weight over time. The results indicate that TNFi therapy itself is unlikely to be the main driver of weight increase in PsA.
Investigators noted that trends in weight change may vary between etanercept and monoclonal antibody TNFi agents, though further research is needed to clarify these differences. Clinicians may consider these findings reassuring when discussing long-term metabolic effects of TNFi treatment with patients managing PsA.
Reference: Kharouf F et al. Changes in weight associated with tumor necrosis factor inhibition in psoriatic arthritis: results from a retrospective cohort study. Clin Rheumatol. 2025; doi: 10.1007/s10067-025-07649-9.
