Reduced non–rapid eye movement sleep is associated with tau pathology in early Alzheimer’s disease

A recent study suggests that a warning sign may come before any symptoms of Alzheimer's disease: Adults who do not get enough deep sleep may be on their way to developing the disease.

Researchers from the Washington University School of Medicine in St. Louis, MO, found that older people who experience less slow-wave sleep (in other words, deep sleep) have elevated levels of a brain protein called tau.

The findings, published in Translational Medicine, note that higher levels of tau are a sign of Alzheimer's disease.

Elevated levels have also previously been associated with both brain damage and cognitive decline.

Slow-wave sleep helps people consolidate their memories and experiences, and getting enough of this type of sleep helps people wake up refreshed and energized.

In order to find out if there is a connection between a lack of deep sleep and the development of Alzheimer's, the authors put together a study that involved 119 people aged 60 years or older.