May 3, 2010 -- A study of nearly 16,000 Chinese adults ages 65 and older has found that those who regularly enjoyed a good night’s sleep were also those who enjoyed overall better health and longevity.
Reporting in the May issue of Sleep, researchers from Portland State University in Oregon analyzed 2005 data from the Chinese Longitudinal Healthy Longevity Survey to look at which factors were associated with sleep among elder adults. They found that those ages 80 and older were more likely to report higher sleep quality compared with adults ages 65 to 79. Being male, living in a rural area, higher socioeconomic status, and good health conditions were all associated with higher quality of sleep.
About two-thirds of the study group rated their sleep quality good or very good. Participants slept an average of 7.5 hours per day, including naps. The findings suggest that the quality of sleep could have implications in living a longer, healthier life.
The Very Old Have Better Sleep
Surprisingly, younger individuals didn’t sleep as well as their elder counterparts. The study showed that adults age 100 and older were 70% more likely to report better sleep quality than those ages 65 to 79, even after controlling for factors such as demographics, socioeconomics, and health. Access to health care services and economic status were strongly associated with higher-quality sleep; participants were 84% more likely to report higher sleep quality if they had sufficient health care access and they were 56% more likely to report good sleep quality if their families were doing well economically. Men were 23% more likely than women to say they slept well.
Not surprisingly, people with health problems were 46% less likely to report sleeping well. Individuals who were anxious, had at least one chronic health condition, or struggled with everyday tasks were less likely to report higher sleep quality.
The study results are based on a population sample of 15,638 adults living throughout China, including 3,927 who were between 90 and 99 years of age and 2,794 who were 100 years of age and older who were interviewed about their sleep habits.
China is an ideal setting to study longevity because its population of 1.3 billion has one of the largest elderly populations in the world. It is estimated that China has nearly 40.5 million people who are age 75 and older.
Good Sleep Promotes Health
While the researchers are not suggesting a cause-and-effect relationship between sleep and healthy aging, the findings do suggest that getting a good night’s sleep may benefit individuals as they age.
"Age and health conditions are the two most important factors associated with self-reported sleep quality and duration," says Danan Gu, PhD. "The majority of healthy elders could experience satisfactory sleep quality. Sleep problems at oldest-old ages likely arise from a variety of physiological and psychosocial factors rather than aging per se."
According to a 2009 survey from the CDC, about one in 10 Americans reported difficulty sleeping; only 30% said they got enough sleep. The survey also showed that an estimated 50 to 70 million Americans have chronic sleep disorders, such as insomnia.