Association Between Glycemic Control and Disease Activity in Rheumatoid Arthritis: A Cross-Sectional Study

Rheumatoid arthritis (RA) is a chronic inflammatory disease that may coexist with diabetes mellitus (DM), complicating management and affecting patient outcomes. Previous studies suggest a link between poor glycemic control and increased inflammation in RA, but data specifically examining this association in patients on tumor necrosis factor inhibitors (TNFi) is limited. This study aimed to investigate the relationship between glycemic control and RA disease activity in patients receiving TNFi. Specifically, we evaluated whether elevated HbA1c levels (≥7%) are associated with higher RA disease activity as measured by the Clinical Disease Activity Index (CDAI) and Disease Activity Score-28 with ESR (DAS28-ESR). A cross-sectional study was conducted on 200 RA patients, divided into equal groups of diabetic and non-diabetic individuals. Diabetic patients were further categorized into well-controlled (HbA1c <7%) and poorly controlled (HbA1c ≥7%) groups. Data were analyzed using Kruskal-Wallis and Mann-Whitney U tests to assess differences in disease activity scores across groups. Spearman’s correlation was used to explore the relationship between HbA1c levels and RA activity. Patients with poor glycemic control showed significantly higher CDAI and DAS28-ESR scores than those with well-controlled diabetes and non-diabetics (p < 0.001). HbA1c levels correlated positively with RA disease activity scores (CDAI: r = 0.27, p= 0.0009, DAS28-ESR: r = 0.29, p= 0.0003), indicating that higher HbA1c levels were associated with increased RA activity. Our findings highlight the potential role of glycemic control in managing RA disease activity. Maintaining HbA1c levels below 7% may help mitigate RA severity, particularly in patients undergoing TNFi therapy, supporting the need for integrated care approaches for RA patients with diabetes.