Seniors taking over nine hours of sleep each night may be facing a higher risk of dementia in later years, a new study has warned.
Boston University researchers found that the risk increased by nearly 2.5 times for those who saw themselves needing extra sleep per night, and the chances actually ballooned six times for those without a high school degree who, fairly recently, needed a shut-eye of more than nine hours.
Dementia patients often already suffer from disturbed sleep, and it remains unknown whether the changes come first. In these new findings, education appeared to offer some protection from the disease.
Dementia-Sleep Link Probed
Study co-author and neurology fellow Matthew Pase said they embarked on a simple question in this new study.
“How does one’s sleep duration relate to being diagnosed with clinical dementia in the future?” he said in a HealthDay report.
The team pored over data from the Framingham Heart Study, which followed individuals and their descendants in Massachusetts since 1948. There were two groups of almost 2,500 elderly or people over age 60 in the research: those from 1986 to 1990, and 1998 to 2001 onward.
In a 10-year period, 10 percent of the subjects developed dementia, with a great majority believed to have Alzheimer’s disease. The team saw no increased dementia risk in individuals who had been sleeping nine hours or more a night for more than a 13-year average.
But there’s another discovery: elderly people who recently started sleeping over nine hours almost doubled their dementia risk versus others. Twenty percent of those who recently started sleeping in were diagnosed with dementia — and demonstrated smaller brain volumes.
According to the author, it seems that the added sleep signals something else and does not cause dementia directly. For instance, it probably reflects chemical changes occurring in the subjects’ brains.
That or the onset of dementia simply makes the patients more tired, Pase added, who clarified they only saw an association and not a cause-and-effect relationship between prolonged sleep and dementia.
He recommended tracking sleep habits, where recent long sleepers could be given memory assessment tests.
The findings were discussed in the journal Neurology.
Other Links To Dementia In Later Life
A separate study published this month hinted that people who maintain risk factors for heart disease during middle age are also at a greater risk for dementia in later years. Analyzing data from over 15,000 adults in the United States who participated when they were 45 to 64 years old, the study saw around 1,500 subjects develop dementia.
Those who had hypertension or diabetes at the beginning of the research — as well as those who smoked — had an elevated dementia risk about 25 years later.
A study in January also provided a link between tiny air pollutants and dementia and cognitive decline. The team explained that the microscopic particles produced by fossil fuels enter the body and into the brain via the nose. The cells in the brain consider these particles invaders, thus they react with inflammatory responses that worsen over time and promote Alzheimer's.
Dementia covered a range of symptoms resulting from brain changes, including memory loss and communication problems. Alzheimer’s is a condition that can cause dementia to occur.