The impact of diabetes mellitus on treatment and outcomes of rheumatoid arthritis at 5-year follow-up: results from a multi-ethnic Asian cohort

OBJECTIVES: We evaluated the impact of type 2 diabetes mellitus (T2DM) on RA treatment and outcomes in a longitudinal RA cohort. METHODS: We analysed data collected in the period 2001–2013 involving 583 RA patients, including demographics, diabetes diagnosis, clinical features, treatment, ACR functional class, HAQ, and quality-of-life measurement using the Short‐Form 36. RESULTS: Seventy-seven (13.2%) of the RA patients had T2DM. DAS28 was not different in patients with T2DM at 5 years post-RA diagnosis. Fewer T2DM patients received MTX than those without T2DM (51% vs 80%, P < 0.001). Using univariate analysis, T2DM patients were more likely to experience poorer outcomes in terms of ACR functional status (P = 0.009), joint surgery (P = 0.007), knee arthroplasty (P < 0.001) and hospital admissions (P = 0.006). Multivariate regression analyses showed more knee arthroplasty (P = 0.047) in patients with T2DM. CONCLUSION: Fewer patients with T2DM received MTX compared with those without T2DM. Patients with RA and T2DM were at higher risk of knee arthroplasty than RA patients without T2DM.