White matter disease and sleep-disordered breathing after acute stroke.

OBJECTIVE: To assess sleep-disordered breathing (SDB) in patients with acute stroke and its relationship to prestroke cerebrovascular disease, particularly leukoariosis. METHODS: The authors studied SDB and CT evidence of prestroke cerebrovascular disease, nonacute brain infarction, and white matter disease (WMD) in 78 previously independent patients with acute stroke. Subjects underwent respiratory sleep studies to determine the Apnea-Hypopnea Index (AHI) and Desaturation Index (DI) 7 to 14 days following stroke. CT scans were evaluated for severity of acute prestroke cerebrovascular disease and WMD severity. RESULTS: Prestroke cerebrovascular disease was present in 49 (63%) patients and was associated with worse SDB (mean AHI 35 vs 23, p < 0.01; mean DI 28 vs 18, p < 0.05), particularly in men (mean AHI 43 vs 27, p < 0.01). WMD severity correlated with AHI (r = 0.26, p < 0.05) and age (r = 0.56, p < 0.01). WMD severity in frontal and basal ganglia areas showed the strongest association. On multivariate analysis, WMD severity correlated independently with AHI (R(2) = 0.07, p < 0.05). CONCLUSIONS: The presence of prestroke cerebrovascular disease and severity of WMD are associated with worse SDB. These findings suggest that either white matter is particularly vulnerable to the hypoxia and blood pressure variability associated with SDB or that WMD is a major factor exacerbating SDB following stroke.