No abstract

Background: Prevalence of vitamin D insufficiency is high in western countries and low vitamin D has been associated with neurovascular injury. To better understand how vitamin D status affects cerebral ischemic susceptibility we assess whether low serum 25-hydroxyvitamin D (25[OH]D), a marker of vitamin D status, is predictive of the ischemic infarct volume and whether it relates to a worse outcome. Methods: We retrospectively analyzed prospective consecutive acute ischemic stroke patients that were evaluated from January 2013 to January 2014 at a tertiary referral center. All patients (n=96) had MRI-proven acute ischemic stroke. Multivariable linear and logistic regression analyses were used to test whether vitamin D represents an independent predictors of infarct volume and poor 90-day outcome (modified Rankin Scale score of >2). Results: There was a significant inverse correlation between infarct volume and serum 25(OH)D concentration in patients with lacunar (r=-.438; p=0.025) as well as non-lacunar (r=-.399; p=0.001) infarcts. Patients with ≥30 ng/mL had smaller infarct volumes than those with <30 ng/mL (Figure). The association of 25(OH)D with ischemic infarct volume was independent of other known predictors of the infarct extent (p<0.001). After adjustment, lower vitamin D (trichotomized as ≥30 vs 29-20 vs <20 ng/mL) was associated with a poor 90-day outcome (OR 9.46, 95%-CI 1.90-47.11, p=0.006). Conclusion: Low vitamin D independently predicts larger infarct volumes and a poor outcome following ischemic stroke. Though causality remains to be proven, our results highlight the need to further explore vitamin D as a promising biomarker for cerebral ischemic vulnerability and potential target for stroke prevention.