- A new study in Neurology links chronic insomnia with a 40% higher risk of later cognitive impairment.
- People with insomnia who also slept less than usual, were more likely to have markers tied to memory problems.
- Starting a nightly routine and advice from a health care professional can help with quality sleep.
Sleepless nights aren’t just exhausting—they may carry implications for long-term brain health. While many of us experience occasional rough patches, chronic insomnia has been increasingly connected to memory and thinking changes as we age. Now, new research published in Neurology, the medical journal of the American Academy of Neurology, adds weight to that concern: older adults with chronic insomnia had a 40% higher risk of developing cognitive impairment (a category that includes MCI and dementia) during follow-up.
What’s especially notable is that the investigators also looked inside the brain. Among people with insomnia who reported sleeping less than usual, imaging at baseline revealed more white matter changes (often a sign of small blood-vessel stress in the brain) and higher amyloid burden (a protein that can accumulate in Alzheimer’s disease). Together, the clinical and imaging findings help explain why persistent sleep problems might track with later cognitive issues.
How Was This Study Conducted?
Researchers drew on data from the long-running Mayo Clinic Study of Aging, which follows older adults over time. They compared participants with and without chronic insomnia and tracked annual cognitive testing alongside brain imaging. Cognitive outcomes included global cognitive scores and diagnostic status (normal, MCI or dementia).
Imaging focused on white matter hyperintensities (WMH) on MRI. White matter hyperintensities are bright spots linked with small-vessel changes. The imaging also included amyloid-PET, which visualizes amyloid accumulation. The team used established statistical models to estimate both the risk of developing cognitive impairment and how cognition and imaging markers changed over time, while adjusting for many health and lifestyle factors.
What Did the Study Find?
In this study, chronic insomnia was linked to a 40% higher risk of developing cognitive impairment over the study period. Second, among those with insomnia who also slept less than their usual amount, baseline testing and scans painted a less favorable brain-health picture—poorer cognitive performance, more WMH and higher amyloid at the outset. Importantly, insomnia was not tied to faster accumulation of WMH or amyloid across follow-up. In plain terms: having insomnia, particularly with less sleep, was linked to greater risk. It wasn’t linked to a faster pace of brain damage later on.
To help interpret the magnitude, the authors note this elevated risk is meaningful—large enough to deserve attention—yet still observational. The study cannot prove that treating insomnia would prevent cognitive impairment; other factors may contribute despite careful adjustments.
This study has some notable limitations. Insomnia was identified from medical records rather than overnight sleep studies. Changes in sleep duration were self-reported and not always measured at the same time as the insomnia diagnosis. And because participants are from a single region, the results might not be generalizable to everyone.
How Does This Apply to Real Life?
If you’re wrestling with ongoing sleep trouble, there’s a lot you can do, starting tonight. Anchor a consistent wake-up time every day (weekends included) to steady your body clock. Build a wind-down routine 30 to 60 minutes before bed: dim the lights, step away from email and doomscrolling and switch to quiet, low-stimulation activities. Get bright outdoor light soon after waking and keep evening light low to reinforce your natural rhythm.
Protect your sleep by reserving the bed for sleep and sex. If you’re awake and frustrated for about 20 minutes, get up and do something calm in dim light until you feel sleepy again. Cut off caffeine by early afternoon, and avoid alcohol for three to four hours before bed. Daily movement, like walking, helps build healthy sleep pressure and brief stress-management practices (slow breathing, progressive muscle relaxation, a short mindfulness session) can reduce nighttime arousal.
For chronic insomnia, ask a health care provider about cognitive behavioral therapy for insomnia. If you snore, wake up gasping or feel excessively sleepy in the day, consider getting screened for obstructive sleep apnea. Talk to a health care professional if your sleep problems persist for three months or more, if you routinely sleep less than six or seven hours despite your best efforts or if sleepiness makes driving unsafe.
Our Expert Take
A large study in Neurology reports that chronic insomnia is associated with a 40% higher risk of developing cognitive impairment, and that people with insomnia who also slept less than usual showed more white matter changes and higher amyloid at baseline. While the research doesn’t prove causation, it’s a clear nudge to take persistent sleep problems seriously. Prioritize a consistent routine, smart light exposure, movement and talk with a health care professional if insomnia sticks around.
