Association of glucose-lowering agents with readmission risk in patients with rheumatoid arthritis and comorbid type...

This study evaluated the clinical value of a "immuno-metabolic co-management" strategy by investigating the association between glucose-lowering agents (metformin, insulin, and acarbose) and readmission risk in patients with rheumatoid arthritis (RA) and comorbid type 2 diabetes mellitus (T2DM). This study included up to 10 years of longitudinal follow-up data from 616 patients with RA and comorbid T2DM. A shared Gamma frailty model was utilized to analyze unplanned readmission. Furthermore, inverse probability of treatment weighting (IPTW) was employed to control for confounding, followed by validation. Subgroup interaction tests and sensitivity analyses were conducted to evaluate model robustness. In the weighted multivariable analysis, metformin and insulin use were significantly associated with a lower risk of readmission (metformin: HR = 0.56, 95%CI: 0.46-0.70, P < 0.001; insulin:HR = 0.65, 95%CI: 0.52-0.81, P < 0.001), respectively, whereas acarbose showed no statistically significant correlation with the readmission risk (HR = 0.97, P = 0.790). Subgroup interaction analyses indicated that the observed associations were largely consistent across clinical strata. Notably, the inverse association with metformin was more pronounced among patients receiving concomitant glucocorticoids (P for interaction = 0.003). These primary findings remained robust in multiple sensitivity analyses. In conclusion, metformin and insulin are associated with a lower risk of unplanned readmission in patients with RA and comorbid T2DM. These findings highlight the potential clinical relevance of "immuno-metabolic co-management", although future prospective studies are needed to validate these observations.