Sleeping Well To Stay Well

If you think you function fine on just five or six hours a sleep a night, you're deluding yourself--according to a number of studies--but okay. However, there are the physical consequences to be paid for lack of sleep. We already know it ups the likelihood of obesity and diabetes, but now researchers have linked less sleep in midlife with high (and worsening) blood pressure.

In the June 8th issue of Archives of Internal Medicine, Kristen L. Knutson, Ph.D., of the University of Chicago, and colleagues reported on a study involving 578 adults whose blood pressure, sleep duration, and other health variables were measured over the course of six years.

The participants slept an average of six hours; only seven subjects averaged eight or more hours of sleep. The researchers found that those who slept fewer hours were significantly more likely to have higher blood pressure. Sleeping less also predicted increases in blood pressure over five years, along with the onset of hypertension. Each hour of reduction in sleep duration was associated with a 37 percent increase in the odds of developing high blood pressure.

"Consistent with other studies, we observed higher blood pressure levels in men, particularly African American men," the authors write. "Also, as described in a previous report from this study, African American men slept much less than white women. These two observations suggested the intriguing possibility that the well-documented higher blood pressure in African Americans and men might be partly related to sleep duration."

"The present study provides evidence for a link between the duration and quality of sleep and high blood pressure levels using objectively measured sleep characteristics," the researchers noted. Almost one-third of Americans have hypertension or high blood pressure, a condition that contributes to 7 million deaths worldwide each year. "Intervention studies are needed to determine whether optimizing sleep duration and quality can reduce the risk of increased blood pressure," they concluded.