Feeling very sleepy during the day? Study reveals its alarming link with dementia

Feeling sleepy during the day at an older age might be tied to a higher risk of dementia. Researchers emphasise the importance of avoiding daytime sleepiness and maintaining mental health.

In Short

• Poor sleep, especially daytime sleepiness, may increase the risk of future dementia
• The link between poor sleep and dementia is less significant when factoring in depression
• Daytime dysfunction seems to be a key factor in dementia

If you're feeling sleepy during the day while doing your daily chores at an older age, then this unassuming inconvenience might be linked to a higher risk of developing a condition called dementia.

Dementia is when the cells in the brain begin to deteriorate and get damaged gradually over time. This affects a person's memory, causes confusion, changes their personality and causes difficulty in doing daily tasks. Older adults are more prone to this condition as it is the fastest-growing neurological disorder in the world. Alzheimer's disease is the most common type of dementia.

Researchers have linked poor sleep and dementia in their new study in the journal Neurology and highlighted that 35.5% of the participants who experienced extreme sleepiness during the daytime developed motoric cognitive risk syndrome.

The study followed 445 older adults (average age 76) for about three years to understand if poor sleep increased their risk of mild cognitive impairment (MCR), a potential precursor to dementia.

Initially, none of the participants had MCR. By the end of the study, 36 participants developed it.

Researchers found that people who reported poor sleep were more likely to develop MCR than those with good sleep quality. However, after adjusting for symptoms of depression, this association weakened, suggesting that poor sleep alone may not be as strong a risk factor for MCR when mental health is also considered.

The study measured sleep quality using the Pittsburgh Sleep Quality Index (PSQI), which assesses factors like sleep duration, disturbances, and daytime alertness. Among these, only "daytime dysfunction" — meaning excessive sleepiness and lower enthusiasm during the day — was linked to a higher risk of MCR.

People with this symptom were more than three times as likely to develop MCR than those without it.

Researchers called for avoiding daytime sleepiness and maintaining proper mental health - two factors linking to dementia.