A new study in the U.S., published in Neurology, warns that excessive daytime sleepiness could be linked to a pre-dementia syndrome, motoric cognitive risk syndrome (MCR). MCR is characterized by slowed walking speed and mild memory issues, even in the absence of a diagnosed mobility disability or dementia.
This research highlights that feeling excessively tired during the day, especially after sleep disturbances or lack of enthusiasm for daily tasks, could indicate a higher risk of developing MCR later in life. As daytime drowsiness is common, the study suggests that individuals experiencing this symptom may need to be screened for underlying sleep issues that could affect their long-term cognitive health.
The study was conducted with 445 participants, averaging 76 years old, none of whom had dementia at the study’s start. These participants completed sleep questionnaires that assessed both nighttime sleep quality and daytime sleepiness. The study tracked their memory concerns, enthusiasm levels, and walking speed initially and annually over three years. Those who reported excessive daytime drowsiness or a lack of enthusiasm were more likely to exhibit characteristics of MCR, such as slower walking speeds and memory complaints, than those without these issues.
The researchers emphasize that while an association was found between sleepiness and MCR, this doesn’t confirm causation. The findings suggest that daytime sleepiness and low motivation may serve as early indicators of potential cognitive decline, particularly in the form of MCR. Sleep disturbances noted by participants included difficulty falling asleep, waking frequently at night, or needing sleep aids, while daytime questions focused on the challenges of staying awake during daily activities.
At the start of the study, 42 participants were already diagnosed with MCR, and 36 additional cases developed over the study period. Results showed that participants with “poor sleep” habits, defined as frequent nighttime disturbances and daytime drowsiness, were more likely to progress to MCR compared to “good sleepers.” This correlation raises important considerations for understanding how sleep quality impacts cognitive health and suggests that addressing sleep issues early could potentially help reduce MCR risk.
Lead author Dr. Victoire Leroy of the Albert Einstein College of Medicine notes the importance of further research into how sleep problems contribute to cognitive decline and MCR. The study’s findings underscore the need for a better understanding of the mechanisms behind sleep disturbances and their impact on cognitive health, aiming to open pathways for early interventions that could slow or prevent cognitive decline related to MCR.
