Cardiovascular events and Multiple Sclerosis

The incidence rate of many cardiovascular events is more than doubled in patients with multiple sclerosis (MS), compared with matched controls without MS, new research shows.

The risk of a major adverse cardiac event (MACE) ― that is, a first myocardial infarction, stroke, or cardiac arrest ― is approximately twofold higher. Venous thromboembolism and peripheral vascular disease also occur at notably increased rates.

Vascular comorbidities are more prevalent in patients with MS than in the general population, but few studies have reported on the incidence of cardiovascular disease after MS diagnosis. To describe rates of incident cardiovascular disease after MS diagnosis and compare them with rates in a matched population without MS, the researchers analyzed data from a U.S. Department of Defense database.

The study included a cohort of 6,406 patients with MS diagnosed and treated during Jan. 2004―Aug. 2017 who had at least one prescription for an MS disease-modifying treatment.

A cohort of 66,281 patients without MS were matched to the patients with MS 10:1 based on age, sex, geographic region, and cohort entry date. The researchers excluded patients with a history of cardiovascular disease or select comorbidities such as dyslipidemia, atrial fibrillation, or a disorder related to peripheral vascular disease. They also excluded patients with a history of treated hypertension or treated type 2 diabetes, defined as diagnosis and treatment within 90 days of each other.

Researchers considered a patient to have a cardiovascular disease outcome ― including MI, stroke, cardiac arrest, heart failure, angina or unspecified ischemic heart disease, transient ischemic attack or unspecified cerebrovascular disease, venous thromboembolism, peripheral vascular disease, pericardial disease, bradycardia or heart block, or arrhythmia other than atrial fibrillation or atrial flutter ― if the disease was recorded five or more times.

The researchers followed patients from cohort entry until study outcome (separate for each outcome), loss of eligibility, death, or end of data collection.

The incidence rates of all cardiovascular disease types, with the exception of bradycardia or heart block, were higher for patients with MS, compared with non-MS patients, the researchers reported.

The incidence rates of venous thromboembolism was more than 2 times higher among patients with MS than among non-MS patients (38.4 vs. 15.1 per 10,000 person-years; IRR, 2.54), as was the risk of peripheral vascular disease (14.9 vs. 6.0 per 10,000 person-years; IRR, 2.49). The relative risk of peripheral vascular disease was higher in women than men, and the risk in patients with MS increased after age 40 years.