Lack of Sleep Linked to Increased Risk of High Blood Pressure
middle age and sleep five or less hours a night, you may be increasing
your risk of developing high blood pressure, according to a study
released by Columbia University's Mailman School of Public Health and
the College of Physicians and Surgeons.
the heart to slow down and blood pressure to drop for a significant
part of the day," said James E. Gangwisch, PhD, lead author of the
study and post-doctoral fellow in the psychiatric epidemiology training
(PET) program at the Mailman School. "However, people who sleep for
only short durations raise their average 24-hour blood pressure and
heart rate. This may set up the cardiovascular system to operate at an
said that 24 percent of people ages 32 to 59 who slept for five or
fewer hours a night developed hypertension versus 12 percent of those
who got seven or eight hours of sleep. Subjects who slept five or fewer
hours per night continued to be significantly more likely to be
diagnosed with hypertension after controlling for factors such as
obesity, diabetes, physical activity, salt and alcohol consumption,
smoking, depression, age, education, gender, and ethnicity.
researchers conducted a longitudinal analysis of data from the
Epidemiologic Follow-up Studies of the first National Health and
Nutrition Examination Study (NHANES I). The analysis is based on NHANES
I data from 4,810 people ages 32 to 86 who did not have high blood
pressure at baseline. The 1982-84 follow-up survey asked participants
how many hours they slept at night. During eight to 10 years of
follow-up, 647 of the 4,810 participants were diagnosed with
people who slept seven or eight hours a night, people who slept five or
fewer hours a night also exercised less and were more likely to have a
higher body mass index. (BMI is a measurement used to assess body
fatness). They were also more likely to have diabetes and depression,
and to report daytime sleepiness.
hypothesized that both BMI and a history of diabetes would mediate the
relationship between sleep and blood pressure, and the results were
consistent with this," Dr. Gangwisch said.
Sleep deprivation has been shown previously to increase appetite and compromise insulin sensitivity.
duration was linked to a new diagnosis of high blood pressure among
middle-aged participants, but the association was not observed among
people age 60 or older, he said. Dr. Gangwisch said the differences
between the younger and older subjects might be explained by the fact
that advanced age is associated with difficulties falling and staying
asleep. Another factor could be that subjects suffering from
hypertension, diabetes, and obesity would be less likely to survive
into their later years.
limitations, researchers found that high blood pressure often goes
undetected. An analysis of NHANES III data showed that over 30 percent
of people who had high blood pressure didn't knowthey had it.
study is based on observational data, Dr. Gangwisch said more research
is needed to confirm the association between short sleep duration and
high blood pressure. "We need to investigate the biological mechanisms
and, if confirmed, design interventions that will help people modify
sleep behavior," he said.
Dr. Gangwisch said the study's main message is clear: "A good night's sleep is very important for good health."
the study include Andrew G. Rundle, DrPH, assistant professor of
Epidemiology at the Mailman School of Public Health; and Columbia
University Medical Center's Dr. Steven B. Heymsfield, Bernadette
Boden-Albala, DrPH; Ruud M. Buijs, PhD; Felix Kreier, PhD; Dr. Thomas
G. Pickering, DPhil; Gary K. Zammit, PhD; and Dr. Dolores Malaspina.
The study was reported in Hypertension: Journal of the American Heart Association.
Support for the study was provided by a National Research Service Award
by the National Institute of Mental Health. For more information on the
Columbia University Mailman School of Public Health, visit www.mailman.hs.columbia.edu.