New research has added to the growing evidence linking sleep disturbances to cognitive impairment. The study found that sleep-initiation insomnia and sleep medication use were associated with a higher risk of developing dementia over a 10-year period.
Additionally, those who reported sleep-maintenance insomnia were less likely to develop dementia. The findings suggest that addressing sleep disturbances may be an important factor in reducing the risk of dementia.
The research published in the American Journal of Preventive Medicine by Elsevier on January 25, 2023, was based on a sample of adults aged 65 and over.
The study analyzed data from 6,284 respondents over a period of 10 years and used Cox regression models to adjust for sociodemographics and health.
The unadjusted model revealed that sleep-initiation insomnia was significantly associated with a 51% increased dementia risk. After adjusting for sociodemographics, sleep medication usage was significantly associated with a 30% increased dementia risk.
However, adjusting for sociodemographics and health showed that sleep-maintenance insomnia was significantly associated with a 40% decreased dementia risk.
These findings indicate that addressing sleep disturbances may be an important factor in reducing the risk of dementia, particularly with regard to sleep-initiation insomnia and sleep medication usage.
“We expected sleep-initiation insomnia and sleep medication usage to increase dementia risk, but we were surprised to find sleep-maintenance insomnia decreased dementia risk,” explained lead investigator Roger Wong, Ph.D., MPH, MSW, an Assistant Professor in the Department of Public Health and Preventive Medicine, SUNY Upstate Medical University, Syracuse, NY, USA.
— 🥼Agingdoc1⭐MD, PhD 🔔 (@agingdoc1) March 7, 2023
Sleep-initiating insomnia and sleep-maintenance insomnia
According to the Sleep Foundation, sleep-initiating, more commonly named sleep onset insomnia, is characterized by difficulty falling asleep at the beginning of the night, which can lead to tossing and turning for extended periods. This type of insomnia can cause reduced total sleep time and daytime sleepiness.
Sleep maintenance insomnia, on the other hand, is the inability to stay asleep through the night, often resulting in waking up at least once and struggling to fall back asleep.
The fragmented sleep associated with this type of insomnia leads to lower sleep quantity and quality, which can cause daytime sleepiness or sluggishness. These sleep disturbances can have negative effects on an individual’s overall health and well-being.
“Older adults are losing sleep over a wide variety of concerns. More research is needed to better understand its causes and manifestations and limit the long-term consequences,” added Dr. Wong.
Moreover, Dr. Wong stated, “Our findings highlight the importance of considering sleep disturbance history when assessing the dementia risk profile for older adults. Future research is needed to examine other sleep disturbance measures using a national longitudinal sample, whether these sleep-dementia findings hold true for specific dementia subtypes, and how certain sociodemographic characteristics may interact with sleep disturbances to influence dementia risk.”