Background and Purpose-Left-sided strokes are reported to be more common than right-sided strokes, but it is unknown whether they occur more often or are simply recognized more easily by clinicians. In a large unselected community-dwelling population, we examined the frequency of clinical left-and right-sided strokes and transient ischemic attacks (TIAs) and compared it with the frequency of left-and right-sided infarcts on MRI.Methods-This study was conducted within the population-based Rotterdam Study. Between 1990 and 2012, 13 894 participants were followed up for first-ever stroke and TIA. MRI scans were performed within a random subgroup of 5081 persons and were rated for the presence of supratentorial cortical and lacunar infarcts. We compared frequencies of left-and right-sided strokes, TIAs, or MRI infarcts using binomial and Fisher exact tests.Results-After a mean follow-up of 9.6 (±6.0) years, 1252 patients had a stroke, of which 704 were ischemic, and 799 participants had a TIA. Within the subgroup with MRI, we identified 673 infarcts. Ischemic strokes were more frequently left-sided (57.7%; 95% confidence interval, 53.7-61.6) than right-sided, similar to TIAs (57.8% left-sided; 53.4-62.3). In contrast, we found no left-right difference in distribution of infarcts on MRI (51.9% left-sided; 48.1-55.6).Conclusions-Clinical ischemic strokes and TIAs are more frequently left-sided than right-sided, whereas this difference is not present for infarcts on MRI. This suggests that left-sided strokes and TIAs are more easily recognized. Consequently, there should be more attention for symptoms of right-sided strokes and TIAs.

epidemiology, magnetic resonance imaging, stroke,
Department of Radiology

Portegies, M.L.P, Selwaness, M, Hofman, A, Koudstaal, P.J, Vernooij, M.W, & Ikram, M.A. (2015). Left-sided strokes are more often recognized than right-sided strokes: The rotterdam study. Stroke, 46(1), 252–254. doi:10.1161/STROKEAHA.114.007385