Sleep disturbances may drive dementia risk

Individuals who have trouble falling asleep and who use sleep medications are at increased risk of dementia, as reported in a study.

The study consisted of 10 annual waves (2011–2020) of prospective cohort data from the National Health and Aging Trends Study and included a nationally representative US sample of adults aged ≥65 years (n=6,284; average age 76.3 years, 55.5 percent women, 81.7 percent non-Hispanic White).

Sleep disturbances were assessed as sleep-initiation insomnia (trouble falling asleep in 30 minutes), sleep-maintenance insomnia (trouble falling asleep after waking up early), and sleep-medication usage (taking medication to help sleep).

On average, the participants reported having sleep-initiation insomnia about 43.0 percent of the time, experiencing sleep-maintenance insomnia about 42.3 percent of the time, and using sleep medication 21.7 percent of the time.

Multivariable Cox regression analysis showed that sleep medication use was associated with a 30-percent increase in the risk of dementia (adjusted hazard ratio [HR], 1.30, 95 percent confidence interval [CI], 1.08–1.56). Meanwhile, sleep-initiation insomnia was associated with a 51-percent risk increase (HR, 1.51, 95 percent CI, 1.19–1.90) only in the unadjusted analysis.

Conversely, sleep-maintenance insomnia was associated with a 40-percent reduction in the risk of dementia (adjusted HR, 0.60, 95 percent CI, 0.46–0.77).

The present data highlight the importance of considering sleep disturbances when assessing the risk profile for dementia. More studies are needed to examine other sleep disturbance measures and to explore the mechanisms for decreased dementia risk among older adults with sleep-maintenance insomnia.