Extended Sleep After Mild Stroke Linked to Cognitive Decline

Recent research highlights a concerning correlation between extended sleep duration or increased time spent attempting to sleep and cognitive difficulties in individuals who have experienced a mild stroke or transient ischemic attack (TIA). Published in the journal Neurology, the study indicates that these sleep-related issues may be indicative of underlying brain health problems, potentially leading to dementia or subsequent strokes.

The study's findings suggest that spending excessive time in bed--whether due to actual sleep or prolonged periods of wakefulness--can signal sleep disorders. Participants who reported longer periods in bed or longer sleep durations exhibited a greater likelihood of cognitive deficits and brain changes. However, the study does not establish a causal relationship between sleep duration and cognitive decline, only an association.

According to the lead researcher, disturbed sleep patterns may serve as a warning sign of declining brain health, particularly in individuals recovering from mild strokes or TIAs. While the detrimental effects of insufficient sleep are widely recognized, the impact of extended sleep periods or increased time spent in bed remains less understood.

The research involved 422 participants, averaging 66 years of age, from Edinburgh and Hong Kong who had recently suffered a mild stroke or TIA. Within one to three months post-stroke, these individuals underwent brain scans, completed sleep-related questionnaires, and participated in cognitive assessments.

On average, participants scored one point on cognitive tests designed to evaluate mild strokes, with scores ranging from one to four. Those who spent more time in bed were more likely to show signs of damage to small blood vessels in the brain, characterized by an increased volume of white matter hyperintensities--areas indicating brain tissue damage. Furthermore, longer sleep durations were associated with the presence of microhemorrhages, small brain bleeds.

The researchers emphasize the need for further investigation to validate their findings and explore the potential adverse effects of prolonged sleep on individuals who have never experienced a stroke or TIA. Additionally, future studies should examine whether improving sleep patterns in stroke patients might mitigate some of these negative effects.

It's important to note that the study was a cross-sectional analysis, providing a snapshot of participants' conditions without tracking changes over time. Researchers did not assess the quality of sleep prior to the strokes, which could be significant in understanding the relationship between sleep and cognitive health.

For more detailed information, the study is available in the journal Neurology.