Editors' note: WMH and long-term outcomes in ischemic stroke: A systematic review and meta-analysis

Abstract

Cerebral microvascular ischemic disease is a leading cause of dementia in the adult population. In their meta-analysis of data from more than 70,000 patients with ischemic stroke, Dr. Georgakis and colleagues examined the association between severity of white matter disease on baseline CT or MRI with 4 outcome measures—all-cause dementia, long-term functional impairment, recurrent stroke, or death due to any cause. Using an elegant mixed-effects regression model, adjusting for multiple hypothesis testing, the investigators observed a significant increased risk of each of these outcome measures among patients with moderate to severe white matter disease when compared with patients with mild to no white matter disease. In response, Dr. Gupta reminds the reader that white matter disease is etiologically heterogeneous and does not always indicate microvascular ischemia—it may be migraine or medication-related—and therefore may not universally portend an increased risk of vascular dementia or other morbidity. The investigators acknowledge this limitation of their meta-analysis; however, the relationship between (nonspecific) white matter disease and clinical outcomes remains robust. Whether the effect may be more strongly driven by patients with microvascular white matter disease and is attenuated by patients with toxic or nonvascular white matter disease remains to be clarified. Cerebral microvascular ischemic disease is a leading cause of dementia in the adult population. In their meta-analysis of data from more than 70,000 patients with ischemic stroke, Dr. Georgakis and colleagues examined the association between severity of white matter disease on baseline CT or MRI with 4 outcome measures—all-cause dementia, long-term functional impairment, recurrent stroke, or death due to any cause.