Cardiovascular disease (CVD) risk is elevated in patients with systemic lupus erythematosus (SLE) and diabetes mellitus (DM), but whether risk of CVD in patients with SLE is as high as in those with DM is unknown. The present study was undertaken to compare CVD risks between patients with SLE and DM and general population US Medicaid recipients.
In a cohort study, we identified age- and sex-matched adults (1:2:4) with SLE or DM and those from the general population using Medicaid Analytic eXtract, 2007-2010. We collected data on baseline sociodemographic factors, comorbidities, and medications. We used Cox regression models to calculate hazard ratios (HRs) of hospitalized nonfatal CVD events (combined myocardial infarction [MI] and stroke) and MI and stroke separately, accounting for competing risk of death and adjusting for covariates. We compared risks in age-stratified models.
We identified 40,212 SLE patients, 80,424 DM patients, and 160,848 general population patients; 92.5% were female, and the mean ± SD age was 40.3 ± 12.1 years. Nonfatal CVD incidence rate per 1,000 person-years was 8.99 for patients with SLE, 7.07 for those with DM, and 2.36 for the general population. Nonfatal CVD risk was higher in SLE compared to DM (HR 1.27 [95% confidence interval (95% CI) 1.15-1.40]), driven by excess risk at ages 18-39 years (HR 2.22 [95% CI 1.81-2.71]). Patients with SLE had higher risk of CVD compared to the general population (HR 2.67 [95% CI 2.38-2.99]).
SLE patients had a 27% higher risk of nonfatal CVD events compared to age- and sex-matched patients with DM and more than twice the risk of the Medicaid general population. The highest relative risk occurred at ages 18-39 years. These high risks merit aggressive evaluation for modifiable factors and research to identify prevention strategies.