Sleep disturbances after cerebral infarction: role of depression and fatigue.

BACKGROUND: Poststroke sleep disturbances (PSSDs) are frequent and reported to be associated with unfavorable clinical outcomes. PSSDs appear to be related to a multitude of factors including lesion location and environmental causes. Moreover, depression and fatigue, which frequently develop in stroke patients may also contribute to PSSD development. The purpose of this study was to evaluate the prevalence and characteristics of PSSDs and factors related to PSSDs including depression and fatigue in hospitalized stroke patients.

METHODS: Patients who were hospitalized with acute stroke at the Asan Medical Center were evaluated. The quality (Verran-Snyder-Halpern [VSH] Sleep Scale score), duration and latency of night-time sleep, the frequency of waking after sleep onset, and daytime sleepiness were evaluated during the hospitalization period. To validate the self-reported night-time sleep, an actigraphy was performed in a subset of patients. The location, circulation, and laterality of each lesion were determined from brain magnetic resonance images obtained within 7 days of stroke onset. Depression and fatigue were assessed using the Beck Depression Inventory and the Fatigue Severity Scale, respectively. For environmental factors, the duration of hospitalization and the number of other patients in the same room were recorded. Univariate, multiple regression, and multiple logistic regression analyses were used to evaluate predictors of PSSD development.

RESULTS: A total of 282 patients completed the study. The mean age of the patients was 62.3 (±12.76) years and 58.9% of them were male. Sixty patients (21.3%) reported sleep duration less than 6 hours/night and 110 (39.0%) reported more daytime sleepiness than before the stroke. In 54 patients who agreed to wear an actigraph, self-reported sleep duration was significantly correlated with time in bed measured with an actigraph (r = .407, P = .002) and, VSH Sleep Scale score and sleep efficiency in actigraphy were also significantly correlated (r = .305, P = .026). Quality of night-time sleep was independently related to cortical lesion location (P = .002), diabetes mellitus (P = .020), and depression (P < .001), whereas increased daytime sleepiness was independently associated with subcortical lesion location (P = .031), fatigue (P = .001), and quality of night-time sleep (P = .001).

CONCLUSIONS: PSSDs are common in hospitalized stroke patients. The most powerful factor predicting night-time sleep disturbances in stroke patients was depression. Cortical brain lesion and diabetes mellitus were also associated with night-time sleep disturbances. On the other hand, although poststroke daytime sleepiness is in part caused by night-time sleep disturbance, it is more closely associated with fatigue and subcortical lesion location.