Sleep habits could predict your dementia risk

by Dan Taylor for Building A Better World:

Researchers at Boston University Medical Center have just made a remarkable discovery, and one that could change how we diagnose dementia in its early stages. They’ve found that sleep habits could predict whether or not you are likely to develop the degenerative brain disease, and specifically that people who sleep more than nine hours per night are at a very high risk of dementia.

Scientists examined 2,400 people who self-reported their sleep duration over a decade and compared their likelihoods of getting dementia based on how much they slept. They found that people who spend nine hours or more asleep were twice as likely to develop dementia over 10 years than those who did not sleep as long.

Scientists say that changes in sleep patterns are one of the big indicators of brain damage, and this finding could open up a whole new way to catch dementia early, potentially allowing doctors to treat it more successfully. Also, it could help scientists understand how dementia works better, possibly leading to new treatments down the road.

Data from the Framingham Heart Study has shown that people who consistently sleep more than nine hours each night had double the risk of developing dementia in 10 years as compared to participants who slept for 9 hours or less. The findings, which appear in the journal Neurology, also found those who slept longer had smaller brain volumes.

It is believed that the number of Americans with Alzheimer’s disease and other dementias will grow each year as the size and proportion of the U.S. population age 65 and older continues to increase. By 2025 the number of people age 65 and older with Alzheimer’s disease is estimated to reach 7.1 million.

A large group of adults enrolled in the Framingham Heart Study (FHS), were asked to indicate how long they typically slept each night. Participants were then observed for 10 years to determine who developed dementia, including dementia due to Alzheimer’s disease. Researchers from Boston University School of Medicine (BUSM) then analyzed the sleep duration data and examined the risk of developing dementia.

“Participants without a high school degree who sleep for more than 9 hours each night had six times the risk of developing dementia in 10 years as compared to participants who slept for less. These results suggest that being highly educated may protect against dementia in the presence of long sleep duration,” explained co-corresponding author Sudha Seshadri, MD, professor of neurology at BUSM and FHS senior investigator.

According to the researchers the results suggest that excessive sleep may be a symptom rather than a cause of the brain changes that occur with dementia. Therefore, interventions to restrict sleep duration are unlikely to reduce the risk of dementia.

“Self-reported sleep duration may be a useful clinical tool to help predict persons at risk of progressing to clinical dementia within 10 years. Persons reporting long sleep time may warrant assessment and monitoring for problems with thinking and memory,” added co-corresponding author Matthew Pase, PhD, fellow in the department of neurology at BUSM and investigator at the FHS.

The researchers believe screening for sleeping problems may aid in the early detection of cognitive impairment and dementia. The early diagnosis of dementia has many important benefits, such as providing a patient the opportunity to more activity direct their future plans and health care decisions.

Source: Building A Better World (no longer available online)