Sleep-Dementia Link Found When Sleeping 9-Plus Hours

Too much sleep has been linked to dementia, according to a new study that suggests snoozing for nine hours or more each night could double the risk.

Those who slept longer than nine hours each night for 10 years had twice the risk of developing dementia as compared to those who slept less, said the study from Boston University School of Medicine researchers which was published in the science journal Neurology.

The researchers followed a large group of adults who enrolled in the Framingham Heart Study for 10 years and asked them to indicate how long they typically slept each night. The researchers then examined the participants’ sleep duration data and risk of developing dementia.

Researchers suggested that excessive sleep may be a symptom rather than a cause of the brain changes that occur with dementia, thus 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,” Matthew Pase, a fellow at the medical school’s neurology department.

“Persons reporting long sleep time may warrant assessment and monitoring for problems with thinking and memory.”

Pase told website HealthDay that dementia tests may be appropriate for older people who notice they’re sleeping longer.

According to HealthDay, the study also suggested that dementia chances increased six-fold for longer sleepers without a high school degree, hinting that education might somehow offer some protection from disease.

Almost 2,500 people from a Massachusetts community took part in the study that followed two groups of people over 60 years old – from 1986-1990 and 1998-2001 onward, according to HealthDay. Their average age was 72 and 57 percent were women.

“While unusual sleep patterns are common for people with dementia, this study adds to existing research suggesting that changes in sleep could be apparent long before symptoms like memory loss start to show,” Rosa Sancho of Alzheimer Research UK told the Daily Mail, adding that more research was needed.

“Understanding more about how sleep is affected by dementia could one day help doctors to identify those who are at risk of developing the condition.”