A recent study published in PLOS Medicine has shown that shorter sleep duration in older adults is associated with multimorbidity, or the diagnosis of two or more chronic diseases such as heart disease, diabetes, or cancer.
The study included over 7,500 participants from the Whitehall II cohort study, which was established in 1985 in London. The participants reported their sleep duration 6 times between 1985 and 2016. The length of time that each participant slept for was then compared to their likelihood of developing two or more chronic diseases out of a list of 13 (diabetes, cancer, coronary heart disease, stroke, heart failure, chronic obstructive pulmonary disease, chronic kidney disease, liver disease, depression, dementia, other mental disorders, Parkinson’s disease, and arthritis).
Compared to people who slept 7 hours at age 50, people who got 5 or less hours of sleep at that age were 20% more likely to develop one chronic disease and 40% more likely to develop two or more chronic diseases during the 25-year follow-up. People who slept 5 or fewer hours at age 50 were also 25% more likely to die during the follow-up than those who slept 7 hours, which can largely be explained by the increase in chronic disease. Increases in disease occurred across age groups; those who slept 5 or fewer hours at ages 50, 60, and 70 were at a 30–40% increased risk of multimorbidity compared to those who slept 7 hours.
These results highlight the importance of prioritizing sleep to optimize health, which has been increasingly studied in recent years. Both quality and quantity of sleep are important; helpful tips include scheduling sufficient time for sleep, keeping your bedroom cool and dark, exercising during the day, and exposing yourself to natural light during the day.