Do you often feel tired or sleepy during the day? It might be more than just a sign of ageing. A recent study has highlighted a concerning link between daytime sleepiness and an increased risk of dementia, particularly in older adults.
Dementia, a condition marked by memory loss and cognitive decline, is most commonly associated with Alzheimer’s disease, a progressive disorder that affects millions of people worldwide. While the risk factors for dementia have been widely studied, recent research is shining a light on sleep—specifically daytime sleepiness—as a critical factor in predicting cognitive decline.
A study published in *Neurology* followed 445 adults, with an average age of 76, over three years to investigate how sleep patterns affect cognitive health. The results were alarming: 35.5% of participants who reported feeling excessively sleepy during the day went on to develop Mild Cognitive Impairment (MCI), a common precursor to more severe forms of dementia. In comparison, only a small percentage of those who remained alert throughout the day developed MCI.
While poor sleep quality at night has long been known to impact cognitive function, this study found that even individuals who slept well at night but experienced daytime drowsiness were more likely to develop cognitive issues. Specifically, those who felt unusually drowsy, lacked energy or struggled to stay awake during the day were found to be more than three times as likely to experience cognitive decline compared to their more alert peers.
One of the take-home messages from this study is that it is the quality of wakefulness during the day–that is, how adequately a person functions during the day is more critical or at least as critical for the risk of dementia as the quality of nighttime sleep.
The authors also accounted for depression, which often co-occurs both with sleep disturbances and with cognitive impairment. This indicates that while sleep is a risk factor for the development of dementia, depression notably aggravates the condition. This therefore means mental health plays a profound role in the prevention of impairment of cognition, and its improvement may not simply depend on sleep quality alone to reduce dementia risks but rather both aspects: sleep quality and emotional status.
Researchers now call for a more holistic approach to ageing and the health of the brain. In addition to good sleep, mental wellness should be maintained through activities stimulating the mind, like reading, problem-solving or social interaction. Physical exercise should be included in the routine since it helps to maintain the brain’s plasticity, thus strengthening the neural connections that are essential for cognitive processes.
Some common sleep disorders among older adults are sleep apnea, restless leg syndrome and insomnia. All these can cause problems in regard to sleep quality and excessive daytime sleepiness. The improvement in sleep quality may be achieved in the treatment of these disorders, whether through drugs or by changing lifestyle such as using CPAP for sleep apnea.
Experts suggest that dementia should be addressed as early as possible. Seniors who have excessive daytime sleepiness or evident decline in cognitive performance are advised to consult a medical professional for help. Cognitive training can be initiated early and even reverse the symptoms of dementia.
Thus, the new research heavily emphasizes a significant relationship between sleep and dementia risk. It shows that focusing attention on the aspects of both sleep patterns and mental well-being can reduce the risk of dementia in older adults. If you often feel drowsy during your daily activities, then it is a wake-up call. In other words, it is time to look into your sleep habits and mental health to protect your brain for a better future.