Risk of Myocardial Infarction and Stroke in Newly Diagnosed Systemic Lupus Erythematosus: A General Population-Based Study

Abstract

Objective: To estimate the future risk and time trends of newly diagnosed myocardial infarction (MI), ischemic stroke, or both (cardiovascular disease [CVD]) in individuals with systemic lupus erythematosus (SLE).

Methods: Using a population-based database that includes all residents of British Columbia, Canada, we conducted a matched cohort study of all patients with incident SLE and up to 10 age-, sex-, and entry time-matched individuals from the general population. We compared incidence rates (IRs) of MI, ischemic stroke, or CVD (i.e., MI or ischemic stroke) between the 2 groups according to SLE disease duration. We calculated hazard ratios (HRs), adjusting for confounders.

Results: Among 4,863 individuals with SLE (86% female, mean age 48.9 years), the IRs of MI, stroke, and CVD were 6.4, 4.4, and 9.9 events per 1,000 person-years, respectively, versus 2.8, 2.3, and 4.7 events per 1,000 person-years in the comparison cohort. Compared with non-SLE individuals, the fully adjusted multivariable HRs among SLE patients were 2.61 (95% confidence interval [95% CI] 2.12-3.20) for MI, 2.14 (95% CI 1.64-2.79) for stroke, and 2.28 (95% CI 1.90-2.73) for CVD. The age-, sex-, and entry time-matched HRs for MI, stroke, and CVD were highest during the first year after SLE diagnosis: 5.63 (95% CI 4.02-7.87), 6.47 (95% CI 4.42-9.47), and 6.28 (95% CI 4.83-8.17), respectively.

Conclusion: Patients with SLE have an increased risk of cardiovascular events, particularly during the first year after diagnosis. Increased vigilance in monitoring for these potentially fatal outcomes and their modifiable risk factors is recommended in this patient population.