Background Both SLE and diabetes mellitus (DM) patients have elevated risks of atherosclerotic cardiovascular disease. Risk of heart failure (HF), an end-stage of cardiovascular disease and a leading cause of hospitalization in the U.S., is also elevated among DM patients, but has not been well studied in SLE. We investigated rates and risks of HF hospitalization among SLE patients compared to age- and sex-matched DM and general Medicaid patients.

Methods We used Medicaid Analytic eXtract (MAX) data, containing billing claims for Medicaid patients from the 29 most populated US states 2007–2010. We identified SLE and DM patients, ages 18–65, using ≥3 ICD-9 codes for SLE or DM, each separated by ≥30 days. Index date was 3rd diagnosis code. We matched each SLE patient at index date to 2 DM patients and 4 general Medicaid patients without SLE or DM, by age at index date and sex. Baseline period was 6 months of continuous Medicaid enrollment prior to index date for all patients. Subjects were followed until death, disenrollment or end of follow-up. We used ICD-9 codes to identify HF hospital discharge diagnosis and calculated rates of first HF hospitalization event per 1000 person-years for each cohort. Cox proportional hazard models, accounting for competing risk of death, estimated hazard ratios (HR) for first HF hospitalization events. In a secondary analysis, we excluded those with baseline HF.

Results 40,212 SLE patients were matched to 80,424 DM and 1 60 848 general patients. In all cohorts, 92% were female, and mean age was 40.3 (±12.1) years. Mean follow-up was 1.8 (±1.1) years for SLE, 1.8 (±1.1) years for DM, and 1.6 (±1.2) years for general patients. Baseline CVD was present in 18% of SLE, 13% of DM and 1% of non-SLE, non-DM cohorts, and baseline HF in 6% of SLE, 5% of DM and <1% of non-SLE/non-DM patients. HF hospitalization rates per 1,000-person years were similar in SLE and DM, both higher than the general population (table 1). Adjusted HRs for first HF hospitalizations were higher among DM and SLE patients compared to non-SLE, non-DM patients. When patients with baseline HF were excluded, HRs for first HF hospitalizations were similar in SLE and DM.

Conclusion SLE and DM patients had significantly higher rates of HF hospitalization than age- and sex-matched general Medicaid patients. The risk of HF hospitalization was >2 x higher among both SLE and DM patients, with important implications for improving care for SLE.

Acknowledgements This study was funded by NIH K24 AR066109 and R01 AR057327.