Lack of Sleep May Increase Dementia Risk

A 30-year study explores the links between sleep deficits and dementia.

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Short sleep duration during midlife could increase the risk of developing dementia later in life, an NIA study suggests. The results appeared online in Nature Communications. 

In prior studies, both insufficient and excessive sleep have been linked to greater risk of developing dementia. Yet it’s been hard to determine whether these sleep changes contribute to the disease or simply reflect early symptoms. Many of the studies on sleep and dementia risk have followed participants for less than a decade and focused on people older than 65. 

In the new study, researchers analyzed data from nearly 8,000 people in Britain starting at age 50. Participants reported how many hours they slept at night between 1985 and 2016, and some of the participants wore accelerometers to measure sleep time. Over the course of the 30-year study, 521 participants received a dementia diagnosis at an average age of 77. 

Analysis of the data showed that people in their 50s and 60s who got 6 hours of sleep or less were at increased risk of developing dementia later. Compared to those getting 7 hours of sleep, people getting less rest each night were 30 percent more likely to be diagnosed with dementia. 

Further research is needed to confirm this connection and understand the underlying reasons. The findings, though, underscore the importance of good sleep habits, which play an important role in learning, memory, mood and overall health.—adapted from NIH Research Matters