Too Much Sleep Could Signal Dementia.

People over age 65 who consistently sleep more than nine hours every night have twice the risk of developing dementia and Alzheimer's disease within the next 10 years when compared to those who sleep less than nine hours a night, according to a team of researchers led by Sudha Seshadri, professor of neurology at Boston University, who analyzed data from the Framingham Heart Study, the nation's longest-running epidemiological initiative, which began in 1948 and has been run by BU since 1971. Seshadri says longer periods of sleep also can be a sign of depression.

The results suggest that longer sleep sessions may be a symptom --rather than a cause--of the brain changes that occur with dementia. It does not mean that family members should intervene by waking up older loved ones, Seshadri advises. Earlier detection, however, can help patients and their families plan and obtain services...