Diabetes-Related Complications and Costs in Medicare Beneficiaries with Comorbid Rheumatoid Arthritis and Diabetes Treated with Abatacept Versus Other Targeted DMARDs

INTRODUCTION: Targeted DMARD (tDMARD) use in patients with rheumatoid arthritis (RA) and type 2 diabetes mellitus (T2DM) may increase whole-body insulin sensitivity. Evidence comparing the T2DM-related clinical and economic impact of abatacept versus other tDMARDs is limited. This study compared differences in T2DM-related healthcare resource utilization (HCRU) and costs in patients with RA and T2DM. METHODS: This retrospective study used 100% Medicare Fee-for-Service claims (parts A/B/D) to identify patients ≥ 65 age, diagnosed with RA and T2DM, and were either TNFi-experienced (switched from a TNFi to another tDMARD) or tDMARD-naïve, initiating their first tDMARD (abatacept, TNFi, or non-TNFi) between 2010 and 2017. Abatacept users were propensity-score (PS) matched to TNFi and other non-TNFi users separately on baseline demographics, comorbidities, medications, T2DM-related HCRU, and costs. Post-index follow-up: until discontinuation of index treatment, disenrollment, death, or end of study period, whichever occurred first. T2DM-related complications and HCRU were assessed. Costs were normalized to per-patient-per-month (PPPM) and inflated to 2019 US$. RESULTS: The TNFi-experienced group included 2169 abatacept/TNFi and 2118 abatacept/other non-TNFi PS-matched pairs; the tDMARD-naïve group included 2667 abatacept/TNFi and 2247 abatacept/other non-TNFi PS-matched pairs. For TNFi-experienced patients, T2DM-related complication rates for inpatient settings PPPM trended lower for abatacept than TNFi (21 vs. 24, p = 0.046) and other non-TNFi groups (21 vs. 26; p < 0.0001). T2DM-related total costs PPPM for TNFi-experienced patients demonstrated lower trends for abatacept than TNFi ($489 vs. $594, p = 0.016) and other non-TNFi users ($493 vs. $606, p = 0.012). CONCLUSIONS: Medicare beneficiaries with RA and T2DM who switch to/initiate abatacept as their first tDMARD have directionally lower rates and costs of T2DM-related complications compared with patients switching to/initiating other tDMARDs. Abatacept treatment may help reduce clinical and economic burdens associated with T2DM in patients with RA. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40744-022-00453-w.