While many people know that persons with dementia often suffer from poor sleep quality, few know that not getting quality sleep increases the risk for the disease. Two new studies from Harvard University now show that getting enough sleep decreases your risk of getting dementia or even death.
The first study by Harvard Medical School researchers was conducted on 2,800 individuals aged 65 and above who participated in the National Health and Aging Trends Study in 2013 and 2014. The researchers compared their (participants’) self-reported sleep characteristics to their development of dementia and/or death after five years. The study found that participants who slept than 5 hours a day were more likely to develop dementia and twice as likely to die as those who get 8 to 9 hours of sleep. Results were constant across demographic characteristics, including age, race, marital status, body weight, and health conditions.
Using wider demographics
The second study included the Netherlands, Finland, and the United Kingdom, with close to 8,000 participants. Imported from a different study, they examined data revealed that sleeping for less than 6 hours from the age of 50 increases dementia risk by 30% in comparison to the normal 7 hours of sleep. The mean age of the participants in this second study was 77.
Participants in the second study were also more demographically diverse, although a substantial portion were white, educated men, and healthier than the average population. The researchers also studied sleeping patterns using a wearable accelerometer that uses body movements to track sleep. Data from the accelerometer confirmed what was filled out by the participants in questionnaires.
Risk at the middle ages
The most impactful revelation by these studies is that lack of adequate sleep in midlife increases the risk for dementia. There are countless reasons for inadequate sleep at that age, including work, pressing deadlines, anxiety, stress, care-taking responsibilities, and insomnia. While most of these circumstances are unavoidable, some can be changed. For example, if you sleep a few hours because you work late, you should consider changing your timetable to avoid getting dementia by your retirement.
