Poor sleep quality and irregular patterns raise the risk of anxiety and substance-use disorders
Published : 19 Sep 2026, 12:20 AM
The type of sleep a person gets may matter as much as how long they sleep when it comes to disease risk, according to a large study of nearly 100,000 people.
Researchers at Peking University analysed health data from 95,559 participants in the UK Biobank, who wore wrist accelerometers for seven consecutive days and nights, reports The Independent.
They tracked participants for an average of nine years and examined links between sleep patterns and more than 1,000 disease outcomes.
The study looked at the duration of each sleep stage -- REM, deep sleep and light sleep -- as well as total sleep time, wakefulness after sleep onset and night-to-night irregularity.
More REM sleep was associated with a lower risk of 83 conditions, including heart failure, dementia and Parkinson's disease.
Greater deep sleep was linked to reduced risk of seven conditions, including type 2 diabetes and clinical depression.
Higher sleep irregularity and frequent waking, meanwhile, were associated with a greater risk of anxiety and substance-use disorders.
Participants who slept six to eight hours regularly carried the lowest disease risk.
Those sleeping under five hours faced elevated risk for 37 conditions, while sleeping over eight hours also carried risk, according to The Independent.
Researchers cautioned the findings were observational and could not establish that sleep patterns directly caused disease.
Still, they said the results support the six-to-eight hour window as a health safeguard for middle-aged and older adults, likely because it allows for more favourable distribution of sleep stages.
