Cerebral Small Vessel Disease Burden in Acute Ischemic Stroke and the Role of Physical Activity: Cross-Sectional Study.

BACKGROUND: Cerebral small vessel disease (cSVD) is a major cause of stroke and cognitive decline. While classical cardiovascular risk factors are well-established contributors to overall cSVD burden, the effect of physical activity (PA) is not fully understood. This study aims to investigate the association between PA and cSVD in patients with acute ischemic stroke (AIS). METHODS: This is a post hoc analysis of data from two randomized stroke trials. cSVD burden was quantified on acute admission magnetic resonance imaging (MRI) markers (microbleeds, lacunes, white matter hyperintensities, and atrophy) with scores ranging 0-4. Pre-stroke PA was assessed by admission questionnaire and categorized into quartiles (first quartile is lowest PA level). Association of PA and cSVD burden was analyzed using ordinal logistic regression. RESULTS: A total of 762 patients with AIS were included. The median (IQR) age was 71 (62, 79), and 279 (37 %) were females. Patients with a cSVD score of 0 constitutes 26%, 38%, 43%, and 57%, through the first to fourth PA quartile. Analyses adjusting for age and sex of higher cSVD score showed the odds ratios of 0.64 (confidence intervals: 0.44-0.93) in the second PA quartile, 0.79 (0.53-1.16) in the third, and 0.51 (0.33-0.76) in the fourth quartile compared to the first and lowest quartile. Multivariable analysis showed 0.63 (0.43-0.93) in second, 0.86 (0.57-1.29) in third, and 0.56 (0.36-0.87) in fourth quartile compared to the first quartile, adjusting for sex, age, lifestyle factors, cardiovascular disease, and pre-stroke functional impairment. CONCLUSION: Among patients with AIS, we found a statistically significant association between the highest PA quartile and lower cSVD burden. The direction of causality cannot be determined due to the study design, but warrants further testing in randomized trials.