In a new study, sleep data reveal that irregular sleep patterns—not just short sleep
Experts have reported that inadequate sleep is associated with diabetes, dementia, and 170 other illnesses that impact a person’s general health.
In a new study, sleep data reveal that irregular sleep patterns—not just short sleep—are linked to higher disease risks, including Parkinson’s, kidney failure, primary hypertension, Type 2 diabetes, and liver and brain diseases.
Scientists from Peking University and Army Medical University analysed sleep patterns in nearly 90,000 adults from the UK Biobank.
Over an average follow-up of 6.8 years, they tracked six major sleep traits—including bedtime, rhythm regularity, and sleep fragmentation—and examined how these linked with the risk of 172 diseases across the body.
The current study, published in Health Data Science, said that in total, 92 conditions were found to have more than 20% of their risk tied to poor sleep behaviour. These included well-known problems like type 2 diabetes and Parkinson’s disease, but also lesser-known links like acute kidney failure.
In addition, irregular bedtime proved especially risky. People who fell asleep after 12:30 a.m. faced a 2.57-times higher risk of developing liver fibrosis or cirrhosis than those with earlier bedtimes between 11:00 p.m. and 11:30 p.m.
Low stability in sleep timing from day to day—known as poor interdaily stability—raised the risk of gangrene by 2.61 times.
Among the 172 diseases linked to sleep, nearly half were specifically tied to disruptions in circadian rhythm. That includes irregular bedtimes, inconsistent sleep-wake cycles, and weak day-night activity patterns.
This study suggests that improving sleep regularity and reducing fragmentation could play a bigger role in disease prevention than previously thought.
By recognising the importance of rhythm and timing, future health strategies may shift from merely encouraging more sleep to promoting better sleep, both in terms of quality and consistency.
For years, health experts have warned that both too little and too much sleep could negatively affect well-being.
Qing Chen, PhD, associate professor at the Institute of Toxicology in the College of Preventive Medicine at the Third Military Medical University (Army Medical University) in China, in a reaction, said sleep regularity (rhythm) should be a consideration because sleep rhythm and sleep duration may be in charge of different aspects of our health.
Chen, the co-lead author of a study, added, “Maybe we only know that sleep deprivation is harmful. No scientist has 100% confidence to tell us when we should sleep or when we should not sleep, or whether there are additional sleep tips that are important for health. This is not enough to make a healthy sleep schedule.”