A new study has found that chronic insomnia may significantly raise the risk of developing dementia later in life. Researchers tracked nearly 3,000 older adults over several years and discovered that those who struggled with insomnia three or more nights per week for at least three months had a 40 percent greater chance of developing cognitive decline or dementia compared to those who reported regular, restful sleep.
The participants, whose average age was around 70, underwent yearly memory and thinking tests along with brain imaging scans. Results showed that people with chronic sleep problems scored lower on cognitive exams and displayed more biological markers associated with Alzheimer’s disease, such as amyloid buildup and changes in brain white matter. The effects of poor sleep were compared to the equivalent of being three and a half years older in brain function.
While the research does not prove that insomnia directly causes dementia, it suggests that consistent sleep disturbances may accelerate brain aging or worsen underlying neurological changes. Experts caution that chronic insomnia may act both as a symptom and a contributing factor in cognitive decline.
Doctors recommend addressing sleep problems early to help protect brain health. Treatments such as cognitive behavioral therapy for insomnia, better sleep hygiene, and lifestyle changes like limiting caffeine or alcohol before bed can improve rest and may lower long-term risk.
The findings add to growing evidence that healthy sleep is vital not only for daily well-being but also for preserving memory and cognitive function into old age.