To identify differences in cerebrovascular risk factors and treatment patterns among stroke patients with and without a known history of multiple sclerosis (MS).

Patients with MS are susceptible to true cerebrovascular ischemic events with an estimated 1 in 10 MS patient deaths attributed to stroke.  However, identification of stroke in such a population may be limited by diagnostic bias towards MS related symptoms. Medical and neurological comorbidities among MS patients are common and known to hasten disability progression necessitating the study of stroke among patients with MS.

We performed a retrospective cohort study using a multi-center institutional stroke registry spanning 2009-2016 for inpatient encounters. To compare study variables, chi-square and Student’s t-test were used.

Among 7,333 patients with ischemic stroke, 22 (0.3%) had a history of MS. The MS group had a greater percentage of women (77% vs. 47%, p=.02) and a younger median age (62.5 vs. 70.0 years, p<0.005) compared to patients without MS. Of the cerebrovascular risk factors investigated, patients with MS had a lower rate of diabetes (18% vs 41%, p=0.03) and atrial fibrillation (0% vs 16%, p=0.04), with similar patterns in hypertension, hyperlipidemia, coronary artery disease, and prior ischemic events. We found no significant difference between symptom onset to hospital arrival time within 4.5 hours (18.2% vs. 29%, p=0.1) or rate of treatment with tissue plasminogen activator (4.8% vs 8.1%, p=0.3).

In a single institutional study, stroke patients with a history of MS were younger and less likely to have typical vascular risk factors as compared to other stroke patients. Though we did not detect any differences in hospital arrival or acute ischemic stroke treatment rates among the two groups, larger studies capturing more MS patients are needed to explore diagnostic delay among MS patients with ischemic stroke as well as the impact on patient outcomes.