A new study has found that those with the least active schedules, and poor sleep quality, are most at risk of death from heart disease, stroke, and cancer. Published in the British Journal of Sports Medicine, findings of the study revealed both physical inactivity and poor sleep are independently associated with a heightened risk of death and/or cardiovascular disease and cancer.
Researchers drew on information provided by 380,055 middle-aged men and women participating in the UK Biobank study. It is tracking the long-term health of more than half a million 37-73 year olds, who were recruited from across the UK between 2006 and 2010. Participants supplied information on their normal weekly physical activity levels, which were measured in Metabolic Equivalent of Task minutes. For example, 600 MET minutes a week is the equivalent of 150 minutes of moderate-intensity activity, or more than 75 minutes of vigorous-intensity physical activity a week.
Physical activity levels were categorised as: high (1200 or more MET minutes/week); medium (600 to less than 1200); or low (1 to less than 600); and no moderate to vigorous physical activity, according to World Health Organization guidelines. Sleep quality was categorised using a 0-5 sleep score derived from chronotype ('night owl' or 'morning lark' preference), sleep duration, insomnia, snoring, and daytime sleepiness: healthy (4 ); intermediate (2-3); or poor (0-1).
Participants' health was then tracked for an average of 11 years up to May 2020 or death, whichever came first, to assess their risk of dying from any cause as well as from all types of cardiovascular disease; coronary heart disease; stroke; all types of cancer; and lung cancer.
The lower the sleep score, the higher were the risks of death from any cause, from all types of cardiovascular disease, and from ischaemic stroke. Lower levels of physical activity amplified the unfavourable associations between poor sleep and all health outcomes, with the exception of stroke. While this is an observational study, and can't establish causality, the study also relied on self-reported data, and the key information on sleep patterns and physical activity was collected at one point in time only.
The researchers concluded, “Physical activity levels at or above the WHO guideline threshold eliminated most of the deleterious associations of poor sleep with mortality. As emerging evidence supports a synergistic effect of sleep and physical activity on health outcomes, future trials concurrently targeting both behaviours are warranted.”
