People with chronic insomnia are 40% more likely to develop dementia or mild cognitive issues, reported a new study published in Neurology.
"Insomnia doesn't just affect how you feel the next day -- it may also impact your brain health over time. We saw faster decline in thinking skills and changes in the brain that suggest chronic insomnia could be an early warning sign or even a contributor to future cognitive problems,” study author, Diego Z. Carvalho, MD, of the Mayo Clinic in Rochester, Minnesota, said in a press release.
For the study, researchers analyzed data from 2, 750 adults with an average age of 70 years old for an average of 5.6 years. Altogether, 16% of participants had chronic insomnia.
At the beginning of the study, participants were asked whether they had been sleeping more or less than usual over the last two weeks. They also underwent neuropsychological tests each year, with a subset undergoing brain scans for amyloid plaques and white matter hyperintensities, areas where small vessel disease may have damaged brain tissue.
Ultimately, 14% of those with chronic insomnia developed mild cognitive impairment or dementia, whereas the same was true for 10% of those without insomnia. After adjusting for factors including use of sleep medications, sleep apnea diagnosis, and age, the researchers found that those with insomnia were 40% more likely to develop mild cognitive impairment or dementia than those without insomnia. They noted, however, that insomnia was not linked to the rate of white matter hyperintensities or amyloid accumulation over time.
"Our results suggest that insomnia may affect the brain in different ways, involving not only amyloid plaques, but also small vessels supplying blood to the brain. This reinforces the importance of treating chronic insomnia - not just to improve sleep quality but potentially to protect brain health as we age. Our results also add to a growing body of evidence that sleep isn't just about rest - it's also about brain resilience,” said Carvalho.
Sources: Science Daily, Neurology
