A regular bedtime is not just for kids. A new study on sleep patterns suggests that a regular bedtime and wake time are just as important for heart and metabolic health among older adults.
In a study of 1,978 older adults, researchers at Duke Health and the Duke Clinical Research Institute found people with irregular sleep patterns weighed more, had higher blood sugar, higher blood pressure, and a higher projected risk of having a heart attack or stroke within 10 years than those who slept and woke at the same times every day.
Irregular sleepers were also more likely to report depression and stress than regular sleepers, both of which are tied to heart health, according to the researchers.
African-Americans had the most irregular sleep patterns compared to participants who were white, Chinese-American or Hispanic, the study’s findings showed.
The findings show an association — but not a cause-and-effect relationship — between sleep regularity and heart and metabolic health, according to the researchers.
“From our study, we can’t conclude that sleep irregularity results in health risks, or whether health conditions affect sleep,” said Jessica Lunsford-Avery, Ph.D., an assistant professor in psychiatry and behavioral sciences and the study’s lead author. “Perhaps all of these things are impacting each other.”
The data suggest tracking sleep regularity could help identify people at risk of disease, and where health disparities may impact specific groups, such as African Americans, she noted.
“Heart disease and diabetes are extremely common in the United States, are extremely costly, and also are leading causes of death in this country,” she said. “To the extent we can predict individuals at risk for these diseases, we may be able to prevent or delay their onset.”
For the study, participants used devices that tracked sleep schedules down to the minute so researchers could learn whether even subtle changes — going to bed at 10:10 p.m. instead of the usual 10 p.m. — were linked to the health of participants.
Study participants ranged in age from 54 to 93. People with diagnosed sleep disorders, such as sleep apnea, were not included in the study, she noted.
The study also tracked the duration of participants’ sleep and whether someone turned in early or was a night owl. According to these measures, people with hypertension tended to sleep more hours, and people with obesity tended to stay up later, the study discovered.
Of all three measures, however, regularity was the best at predicting someone’s heart and metabolic disease risk, the researchers found.
As one might expect, irregular sleepers experienced more sleepiness during the day and were less active, perhaps because they were tired, Lunsford-Avery said.
The study was published in the journal Scientific Reports.
Source: Duke University Medical Center