A major UK Biobank study shows that inconsistent sleep timing, not just sleep duration, is associated with increased risk for 172 diseases, including liver cirrhosis and cardiovascular conditions
A significant study conducted by researchers from Peking University and Army Medical University has shed light on an intriguing aspect of sleep that could fundamentally change our understanding of its role in long-term health. The research indicates that irregular sleep patterns, rather than simply the amount of sleep one gets, are closely associated with an elevated risk of developing a staggering 172 different diseases. Among these conditions are serious health issues, such as liver cirrhosis and various cardiovascular diseases.
Analysing sleep data from over 85,000 people
This groundbreaking study, recognised as one of the most comprehensive investigations into the relationship between sleep and health, reveals that the timing and consistency of our sleep schedules may be more crucial than the total hours spent sleeping. The analysis emphasises the idea that sleep quality and patterns are critical indicators of our overall health status.
In their meticulous inquiry, the researchers examined the sleep data of over 88,000 adults, revealing striking correlations between various sleep traits and the incidence of numerous diseases. They carefully considered six specific sleep-related characteristics, which included factors such as how long individuals slept at night, the timing of sleep onset, the rhythm of their sleep (including the strength of their circadian rhythm and overall stability), and the extent of sleep fragmentation, which encompasses the efficiency of sleep and the frequency with which individuals wake up during the night.
Link between irregular sleep and diseases
The findings strongly suggest that poor sleep behaviours are causally linked to numerous health complications. The researchers found that for 92 distinct diseases, over 20% of the associated risk could be attributed to irregular sleep patterns. For instance, individuals who consistently went to bed after 12:30 a.m. faced a staggering 2.57 times greater risk of developing liver cirrhosis. Moreover, low levels of stability in sleep patterns were found to increase the likelihood of gangrene by 2.61 times.
Interestingly, this study also challenges the longstanding notion that excessively long sleep durations, particularly those exceeding nine hours, are inherently harmful. While some previous subjective research has suggested links between extended sleep and adverse health outcomes such as strokes and heart disease, the new objective data confirms this only for one disease. A potential source of confusion arises from the misclassification of sleep duration; astonishingly, about 21.67% of individuals categorised as “long sleepers” were getting less than six hours of sleep. This suggests a significant misinterpretation where the time spent in bed is often mistaken for actual sleep.
Prof. Shengfeng Wang, the senior author of the study, commented, “Our findings underscore the overlooked importance of sleep regularity. It’s time we broaden our definition of good sleep beyond just duration.”
Moreover, the implications of this study extend beyond individuals to encompass public health policies and recommendations. Health practitioners may need to consider advising patients not only on the duration of their sleep but also on the importance of establishing a regular sleep schedule. As society becomes increasingly aware of the consequences of irregular sleep patterns, this research could ultimately influence guidelines surrounding sleep hygiene, potentially leading to significant improvements in community health outcomes. By emphasising the significance of sleep consistency, the findings could pave the way for more comprehensive strategies to combat the rise of sleep-related health issues and promote better overall wellness.
