Less sleep associated with higher risk for multiple chronic diseases

Getting fewer than 5 hours of sleep a night in mid-to-late life was linked to a higher risk for multiple chronic diseases, a recent study published in PLOS Medicine found.

While the association between multimorbidity and sleep duration is “poorly understood,” Séverine Sabia, PhD, an epidemiologist at University College London’s Institute of Epidemiology & Health, and colleagues wrote that “primary prevention of a first chronic disease and secondary prevention to reduce risk of multimorbidity among those with a first chronic disease are ... important in addressing the burden of multimorbidity.”

Sleep duration implications are also relevant in countries like the U.S. According to CDC data, Americans aged 45 to 64 years had the second-highest crude prevalence of short sleep durations (34.5%; 95% CI, 33.9-35.1) among all age demographic subgroups in 2020.

Sabia and colleagues drew data from the Whitehall II cohort study, which was established in 1985 to 1988 and measured self-reported sleep duration six times until 2015 to 2016. The analysis included 10,308 British participants who had data extracted at age 50 (n = 7,864), 60 (n = 6,848) and 70 (n= 5,546) years.

The researchers discovered that fewer than 5 hours of sleep resulted in a higher risk for multimorbidity among:

• participants aged 50 years (HR = 1.3; 95% CI, 1.12-1.5);

• participants aged 60 years (HR = 1.32; 95% CI, 1.13-1.55); and

• participants aged 70 years (HR = 1.4, 95% CI, 1.16-1.68).

Of the participants aged 50 years who had sleep duration data, 4,446 developed a first chronic disease, while 2,296 developed multimorbidity. Overall, 787 participants with multimorbidity died.

Too much sleep was also associated with an increased risk for multimorbidity. Participants aged 60 (HR = 1.54, 95% CI, 1.15-2.06) and 70 (HR = 1.51, 95% CI, 1.1-2.08) years who reported sleeping 9 hours or more per night had a greater risk for multimorbidity compared with those with a sleep duration of 7 hours. There was no significant association for those aged 50 years (HR = 1.39, 95% CI, 0.98-1.96).

Sabia and colleagues highlighted several key findings, one being the consistent association between shorter durations of sleep and higher risk for multimorbidity, “irrespective of sleep being measured in mid- or late-life.”

The researchers also noted that using the accelerometer-based measure for sleep duration, performed at the mean age of 69 years, confirmed the shape of the association of multimorbidity and matched self-reported data of participants aged 60 and 70 years.

The researchers acknowledged bias in self-reporting data as a potential limitation to the study, while data on quality sleep was only available through participants aged 60 and 70 years. Participants were also likely healthier than the general population.

Sabia and colleagues recommended that future research utilize objective measures of sleep duration to allow for a better understanding of its importance regarding multimorbidity and chronic disease association. They concluded that the results of the current analysis “support the promotion of good sleep hygiene in both primary and secondary prevention by targeting behavioral and environmental conditions that affect sleep duration and quality.”

References:

• Sleep and sleep disorders: Adults. https://www.cdc.gov/sleep/data-and-statistics/adults.html#data-table-AdultDemographics.csv. Accessed Oct. 18, 2022.
• Five hours’ sleep a night linked to higher risk of multiple diseases. https://www.eurekalert.org/news-releases/967981. Published Oct. 18, 2022. Accessed Oct. 18, 2022.
• Sabia S, et al. PLoS Med. 2022;doi:10.1371/journal.pmed.1004109.