Impact of Obesity on Response Rate for Biological Agents in Rheumatoid Arthritis: A Systematic Review and Meta-Analysis of Cohort Studies

Background: Existing evidence suggests that obesity has an impact on the onset and development of rheumatoid arthritis (RA) and may also affect the response of patients to different treatments. However, findings from previous studies are controversial. This study aims to obtain evidence-based medical information on the influence of obesity on the response rate of biological agents in patients with RA through a systematic review and meta-analysis. Methods: A search was performed on Pubmed, Medline, Web of Science, Scopus, and Cochrane Library from their inception to June 2023. Studies that met the inclusion criteria were enrolled. A meta-analysis was used to evaluate remission, response, good European League Against Rheumatism (EULAR) response, moderate EULAR response, retention rate, and clinical disease activity index (CDAI). Subgroup analysis was carried out to identify sources of heterogeneity and sensitivity analysis was performed. Results: A total of 15 articles met the inclusion criteria and four biological disease-modifying antirheumatic drugs (bDMARDs) were included. The meta-analysis showed that the odds of reaching good EULAR response or achieving CDAI were lower in obese than in non-obese patients treated with bDMARDs. Subgroup analysis revealed significant differences between the two groups. Remission, good EULAR response and retention rate were lower in the obese group than in non-obese patients treated with tumor necrosis factor inhibitors (TNFi). However, there was no significant difference between patients receiving abatacept and tocilizumab treatment. Sensitivity analysis and publication bias confirmed that the results were highly reliable and stable. Conclusions: Obesity affects the clinical response rate of RA patients receiving TNF inhibitors (TNFi), but it does not have an adverse effect on abatacept and tocilizumab. This suggests that when choosing biological agents for RA patients, the impact of obesity should be considered. Further research is needed to validate these findings.