American scientists have established that chronic insomnia and short sleep duration accelerate neurodegeneration and increase the probability of dementia in people over 50.
Chronic insomnia can cause changes in the brain that raise the risk of developing dementia. This conclusion was reached by American researchers from the Mayo Clinic, who analyzed data from over 2,700 individuals aged 50 and older, as reported by the National Library of Medicine.
Over a period of five and a half years, participants annually underwent cognitive tests, and some received brain MRI scans. This allowed scientists to track key markers of neurodegeneration—the accumulation of amyloid plaques and white matter damage.
The study results showed that people with chronic insomnia had a 40% higher risk of cognitive impairment compared to those with normal sleep. The combination of insomnia and reduced sleep duration was particularly detrimental: these participants’ cognitive function levels corresponded to those of people four years older, and they also showed higher levels of amyloid and white matter lesions.
Scientists explain that sleep disturbances trigger two parallel processes: amyloid plaques impede neuronal function, and white matter hyperintensities disrupt signal transmission between brain regions. Together, they accelerate cognitive decline and increase the likelihood of dementia.
At the same time, the research showed that people with insomnia who were able to increase their sleep duration experienced less white matter damage, indicating the importance of correcting sleep patterns for maintaining brain health.
