MRI Predictors of Cognitive Function After Lacunar Infarction

BACKGROUND: Poststroke cognitive impairment is associated with disability and decreased quality of life. We assessed whether individual or collective magnetic resonance imaging (MRI) biomarkers can aid in predicting cognitive impairment after lacunar infarction (LACI). METHODS: We conducted a retrospective analysis of data from the American Stroke Association Bugher Small Vessel Study, which included 134 patients within 2 years of an acute LACI, enrolled between 2007 and 2012 at 4 North Carolina hospitals. MRI brain measures at the time of the stroke included as follows: 1, total number of LACIs (index LACI and nonindex radiographic lacunes); 2, size of the largest lacune; 3, ventricular size; 4, cerebral atrophy; 5, radiographic locations (supratentorial, infratentorial, or both); and 6, white matter disease (WMD) extent. WMD extent, cerebral atrophy, and ventricular size were graded using the CHS (Cardiovascular Health Study) scores. The primary outcomes were as follows: 1, total score on Short-Form Montreal Cognitive Assessment to assess global cognition; and 2, time to complete TRAIL Making Test Part B (TMT-B) to evaluate executive function. Regression analyses were used to assess the association between the 6 MRI measures and cognitive function adjusting for demographic and clinical variables. RESULTS: One hundred thirty-four participants completed Short-Form Montreal Cognitive Assessment testing and 100 completed TMT-B at a mean of 76.5 (SD, 172.7) days from the index LACI. There were no associations between MRI characteristics and Short-Form Montreal Cognitive Assessment. On univariable analyses, cerebral atrophy (β=35 [95% CI, 14.17–55.83]; P =0.0010), ventricular size (β=40.1 [95% CI, 22.24–57.96]; P <0.0001), and WMD extent (β=55.25 [95% CI, 38.52–71.98]; P <0.0001) were each associated with TMT-B time. Extent of WMD was the only MRI measure associated with TMT-B time (β=37.74 [95% CI, 19.04–56.44]; P <0.0001). In adjusted models after performing variable selection, the extent of WMD remained the only MRI measure associated with TMT-B time. CONCLUSIONS: Among the assessed MRI measures, only the extent of WMD was independently associated with executive function after LACI.