Rich folks get more sleep – blacks and men get less

By Anne Harding

NEW YORK (Reuters Health) – In a study of sleep
characteristics in 669 adults in Chicago who were compared by
sex and race, investigators found that blacks got less sleep
than whites, while men got less sleep than women.

Furthermore, the wealthier you are, the more sleep you’re
likely to get, Dr. Diane S. Lauderdale of the University of
Chicago and her colleagues found.

“There was an expectation that people with very demanding
jobs in terms of high status, high income, would be getting
less sleep, and that was not true,” Lauderdale told Reuters
Health in an interview. The findings could help explain why
blacks suffer from more health problems than whites, she added.

She and her colleagues monitored sleep in a group of men
and women, most in their 40s, who were participating in a large
study of heart disease risk. Fifty-eight percent were female
and 44 percent were black.

Participants told the researchers how much sleep they
thought they were getting, and then kept track of the time
spent in bed and asleep using sleep logs. Researchers also
fitted them with wristwatch-like devices known as actigraphs
that recorded their activity for three days, including two
weeknights and one weekend night.

While people thought they were getting about seven hours of
sleep nightly, they were really getting only about six hours,
the researchers report in the American Journal of Epidemiology.
On average, white women slept 6.7 hours a night, white men
slept 6.1 hours, black women slept 5.9 hours, and black men
slept 5.1 hours nightly. The racial and sex differences
remained even after the researchers factored in the effects of
socioeconomic factors such as employment and lifestyle.

The amount of sleep people got increased with their income,
and this effect was stronger for the black participants than
the whites.

There are a number of potential explanations for the
findings, Lauderdale noted. People who make less money may have
more worries that prevent them from sleeping well. They could
be living in noisier, less comfortable environments, and they
may have more health problems.

The racial and economic sleep differences detected in this
study could help explain the well-known disparities in health
that exist between blacks and whites, she added.

“There are so many inequalities in health — sleep can be
involved in that,” Lauderdale explained. “Sleep seems to be
related to social differences in a way that we never realized.”

SOURCE: American Journal of Epidemiology, July 1, 2006.