Poor sleepers may be at increased risk for cardiovascular disease.
Chinese researchers used data on 487,200 people ages 30 to 79, generally healthy at the start of the study. The participants reported on the frequency of three symptoms of poor sleep: difficulty falling or staying asleep, daytime sleepiness and early morning awakening. The study is in Neurology.
The scientists followed the group for an average of 10 years, during which there were 130,032 cases of cardiovascular disease.
After adjusting for age, alcohol consumption, family history of cardiovascular disease and many other factors, they found that difficulty falling asleep was associated with a 9 percent increased relative risk for cardiovascular disease, early morning awakening with a 7 percent increased risk, and daytime sleepiness with a 13 percent increased risk. Compared with those who had no sleep problems, those with all three symptoms had an 18 percent increased relative risk of cardiovascular disease. The link was especially strong in younger people.
The lead author, Canqing Yu, an associate professor at Peking University, noted that the sleep data depended on self-reports, and this observational study does not prove cause and effect.
“People with difficulty sleeping shouldn’t be alarmed by this finding,” he said. “Poor sleep is a minor contributor to cardiovascular disease. But among young people who have no other risk factors, this can be important.”