Loss of slow-wave sleep as you age may increase your risk of developing dementia, according to a new Australian study.
“We found that aging was associated with a decline in the amount of the deepest stages of sleep, known as slow wave sleep,” Matthew P. Pase, an associate professor of psychology and neurology at Monash University in Melbourne, said.
“We then found that persons with greater declines in slow wave sleep over time had a higher risk of getting dementia over the next 17 years of follow-up.”
Slow-wave sleep is the third stage of sleep, which is important for brain health.
During this stage, the body removes unwanted, or potentially harmful, materials from the brain — including beta-amyloid protein, a hallmark sign of Alzheimer’s disease.
For the brain, this deep sleep is thought to be the most restorative.
The study, which was published in journal JAMA Neurology, sought to find out if chronic reductions in slow-wave sleep over time are linked with dementia risk.
Pase also wanted to determine if dementia-related processes in the brain contributed to getting less of this type of sleep.
“Results suggest that chronic declines in slow wave sleep, rather than individual differences at any given time, are important for predicting dementia risk,” Pase said.
The researchers studied 346 people who were aged 69 on average and had participated in the Framingham Heart Study and completed two overnight sleep studies — one between 1995 to 1998 and the second between 1998 to 2001 — during which their sleep was monitored.
Launched by the US National Heart, Lung and Blood Institute in 1948, the Framingham Heart Study identifies common factors contributing to cardiovascular disease.
The authors also investigated whether any changes in the amount of slow-wave sleep that participants got was associated with developing dementia up to 17 years after they completed the sleep studies.
By that time, 52 participants had been diagnosed with dementia.
(9 NEWS)
