Chronic Insomnia and Dementia Risk

Avoiding chronic insomnia might be crucial for reducing dementia risk. Factors like age, genetics, high blood pressure, uncontrolled type 2 diabetes, smoking, and untreated hearing loss are significant contributors to dementia, which impacts memory, thinking, and daily functioning.

Researchers at the Mayo Clinic set out to understand how long-term insomnia might influence brain aging and dementia risk. Sleep plays a vital role in essential brain functions, including cell repair and toxin removal.

“Insomnia isn’t just about feeling tired the next day; it can have lingering effects on brain health,” says a study author from Mayo Clinic, Dr. Diego Z. Carvalho.

The team observed 2,750 cognitively healthy seniors, averaging 70 years old, over a five-year period.

Participants underwent yearly tests for memory and thinking, and some received brain scans to check for signs of dementia, like Alzheimer’s, which is the most common form.

About 16% of the participants experienced chronic insomnia, classified as sleep issues lasting at least three days a week for over three months.

Among this group, 14% developed either mild cognitive impairment or dementia, compared to 10% of those without insomnia.

The researchers factored in age, high blood pressure, the use of sleeping pills, and sleep apnea diagnoses.

They determined that chronic insomnia increases the risk of mild cognitive impairment or dementia by 40%, which is roughly equivalent to about 3.5 years of aging.

Interestingly, those who reported sleep difficulties at the study’s start had lower initial cognitive test scores and exhibited more signs of amyloid plaque, which is linked to preclinical dementia.

Participants with the APOE E4 gene variant, associated with a higher Alzheimer’s risk, showed a sharp decline in memory and thinking skills over the study period.

Conversely, those who reported better-than-average sleep quality tended to have lower white matter intensity.

“This highlights the importance of treating chronic insomnia, not just to enhance sleep quality but also potentially to safeguard brain health as we grow older,” Carvalho emphasized.

“Our findings reinforce the idea that sleep is about more than just rest; it’s also crucial for brain resilience.”

The study results were published in a recent edition of medical journals by the American Academy of Neurology.

However, a limitation is that the data were based on medical records which might miss undiagnosed insomnia or fail to capture insomnia severity.

The American Academy of Sleep Medicine states that about 12% of Americans are affected by chronic insomnia.

Potential treatments include changing bad habits like reducing alcohol and caffeine intake before bed, using prescription medications, and engaging in cognitive behavioral therapy to address thoughts and behaviors that lead to insomnia.