According to studies by the Karolinska, people with sleep disorders have an older brain more often for the imaging of the brain. An increased inflammatory activity in the body could partially explain this connection. Poor sleep is associated with dementia, but it is unclear whether it contributes to its origin or is an early symptom of the disease. In a new study, scientists examined the connection between sleep properties and the age of the brain compared to chronological age. 27,500 people took part in the study, which underwent a magnetic resonance imaging of the brain. With the help of this technology, they estimated the biological age of the brain based on thousands of resonance phenotypes.
The sleep quality was determined on the basis of five factors: chronotype (early riser or late riser), sleeping time, sleep disorders, snoring and daily fatigue. The participants were then divided into three groups: healthy (≥ 4 points), average (2–3 points) and poor (≤ 1 point). “The gap between brain and chronological age increased by six months per point less sleep,” said Abigail Dove. “People with bad sleep have a brain that is on average one year older than she.”
In order to understand how lack of sleep on the brain, they examined the extent of inflammation in the body. This can explain about 10 % of the connection between lack of sleep and brain. “Our results show that lack of sleep can accelerate brain alternating and that inflammation could be one of the mechanisms. Since sleep is variable, it is possible to prevent accelerated brain age and cognitive breakdown through good sleep.” Other mechanisms that explain the connection are the negative effects on the brain cleaning system, which is more active at night, or the effects of lack of sleep on cardiovascular health and subsequently on the brain.
