In patients with multiple sclerosis (MS), the risk of acute myocardial infarction (AMI) is elevated but may not be accounted for by traditional vascular risk factors, a new study found. Researchers conducted a retrospective matched cohort study using population-based administrative data in 2 Canadian provinces. Incident MS cases were identified and for each case, up to 5 controls without MS were matched on age, sex, and region. The incidence of AMI between cohorts was compared using incidence rate ratios (IRRs). Among the findings:
- 14,565 persons with MS and 72,825 matched controls were identified.
- The crude incidence of AMI per 100,000 population was 146.2 in the MS population vs 128.8 in the matched population.
- After age standardization, the incidence of AMI was higher in the MS population vs the matched population (IRR 1.18).
- After adjustment, the hazard of AMI was 60% higher in the MS population vs the matched population (hazard ratio 1.63).
Marrie RA, Garland A, Schaffer SA. Traditional risk factors may not explain increased incidence of myocardial infarction in MS. [Published online ahead of print March 6, 2019]. Neurology. doi: 10.1212/WNL.0000000000007251.