Older Men at High Risk of High Blood Pressure If Not Getting Ample Deep Sleep
Reduced level of dreamless, deep sleep is powerful predictor of hypertension; as important to
health as diet and exercise
Aug. 29, 2011 – Older men with low levels of slow wave sleep (SWS) - one of the deeper stages
of sleep – are at high risk of developing high blood pressure, according to new research in
Hypertension: Journal of the American Heart Association. Average age of the men in the study was 75.
Researchers from the Outcomes of Sleep Disorders in Older Men Study (MrOs Sleep Study) found
that people with the lowest level of SWS had an 80 percent increased risk of developing high blood pressure.
SWS is characterized by non-rapid eye movement (non-REM) from which it’s difficult to awaken.
It’s represented by relatively slow, synchronized brain waves called delta activity on an electroencephalogram.
Men who spent less than 4 percent of their sleep time in SWS were significantly more likely
to develop high blood pressure during the 3.4 years of the study.
Men with reduced SWS had generally poorer sleep quality as measured by shorter sleep duration
and more awakenings at night and had more severe sleep apnea than men with higher levels of SWS.
However, of all measures of sleep quality, decreased SWS was the most strongly associated
with the development of high blood pressure. This relationship was observed even after considering other aspects of sleep quality.
Participant’s average body mass index was 26.4 kg/m2. But the study effects of SWS
were independent of obesity and continued to be seen after considering the effects of obesity.
The researchers conducted comprehensive and objective evaluation of sleep characteristics
related to high blood pressure in 784 men who didn’t have hypertension.
They were studied in their own homes using standardized in-home sleep studies, or
polysomnography, with measurement of brain wave activity distinguishing between REM and non-REM sleep, and sleep apnea through measurement of
breathing disturbances and level of oxygenation during sleep.
Using a central Sleep Reading Center directed by Redline, the researchers assessed a wide
range of measurements of sleep disturbances, such as frequency of breathing disturbances, time in each sleep state, number of nighttime
awakenings, and sleep duration.
“Our study shows for the first time that poor quality sleep, reflected by reduced slow wave
sleep, puts individuals at significantly increased risk of developing high blood pressure, and that this effect appears to be independent of
the influence of breathing pauses during sleep,” said Susan Redline, M.D., the study’s co-author and Peter C. Farrell Professor of Sleep
Medicine in the Department of Medicine at Brigham and Women’s Hospital and Beth Israel Deaconess Medical Center, Harvard Medical School in
The participants were an average 75 years old and almost 90 percent were Caucasian. All were
healthy and living in one of six communities, geographically representative of the United States: San Diego, Calif.; Palo Alto, Calif.;
Pittsburgh, Pa.; Minneapolis, Minn.; Birmingham, Ala.; and Portland, Oregon. The study was coordinated by California Pacific Medical Center.
Older People Have More Trouble Sleeping
Generally, older men and women are more likely to develop high blood pressure than younger
people. Sleep disorders and poor quality sleep are more common in older adults than in younger ones. Obesity is also associated with
hypertension, researchers said.
In the Sleep Heart Health Study, another large cohort study, researchers found that men were
more likely to have less SWS than women. Men were also at an increased risk of high blood pressure when compared to women. The current study
raises the possibility that poorer sleep in men may partly explain the male gender predisposition to high blood pressure.
Older Women May Also Have Higher Risk
“Although women were not included in this study, it’s quite likely that those who have lower
levels of slow wave sleep for any number of reasons may also have an increased risk of developing high blood pressure,” Redline said.
Slow wave sleep has been implicated in learning and memory with recent data also highlighting
its importance to a variety of physiological functions, including metabolism and diabetes, and neurohormonal systems affecting the sympathetic
nervous system that contribute to high blood pressure, researchers said.
Good quality sleep is the third pillar of health, Redline said.
“People should recognize that sleep, diet and physical activity are critical to health,
including heart health and optimal blood pressure control. Although the elderly often have poor sleep, our study shows that such a finding is
not benign. Poor sleep may be a powerful predictor for adverse health outcomes. Initiatives to improve sleep may provide novel approaches for
reducing hypertension burden.”
The primary author of the study is Maple Fung, M.D. formerly of the University of California,
San Diego. The study is coordinated by the San Francisco Coordinating Center, under the direction of Principal Investigator Katie L. Stone,
Ph.D. at California Pacific Medical Center Research Institute.
Co-authors are Maple M. Fung, M.D.; Katherine Peters, M.S.; Michael G. Ziegler, M.D.; Sonia
Ancoli-Israel, Ph.D.; Elizabeth Barrett-Connor, M.D.; and Katie L. Stone, Ph.D. Author disclosures and sources of funding are on the
Older adults need about the same amount of sleep
as younger adults (7 to 9 hours nightly), according to Mayo
Clinic sleep specialist Timothy Morgenthaler, M.D.
study published in the February, 2010, issue of the journal
SLEEP, reported older adults sleep about 20 minutes less than
middle-aged adults, who sleep 23 minutes less than young adults.
“As you get older, however, your sleeping
patterns may change. Older adults tend to sleep more lightly and
awaken more frequently during the night than do younger adults.
This may create a need for or tendency toward daytime napping,”
writes in a
Mayo Clinic Q&A.
“If your sleep is frequently interrupted or cut
short, you're not getting quality sleep — and the quality of
your sleep is just as important as the quantity,” he adds.
Dr. Morgenthaler points out that lack of sleep
can affect your immune system.
“Studies show that people who don't get a good
night's sleep or who don't get enough sleep are more likely to
get sick after being exposed to a virus, such as the common
cold. Lack of sleep can also affect how fast you recover if you
do get sick,” he says.
“During sleep, your immune system releases
proteins called cytokines. These substances increase in the
presence of an infection, inflammation and stress. Increased
cytokines are necessary in fighting infection and regulating
deeper sleep. In addition, other infection-fighting cells are
reduced during periods of sleep deprivation. So, your body needs
sleep to fight infectious diseases.
“How much sleep do you need to bolster your
immune system? The optimal amount of sleep for most adults is
seven to eight hours a night. School-aged children and
adolescents need nine or more hours of sleep a night.
“But be careful; more sleep is not always better.
For adults, sleeping more than nine to 10 hours a night has been
associated with weight gain, heart problems, stroke, sleep
disorders, depression and other health concerns.”