Tuesday November 11, 2008 (foodconsumer.org) -- Sleeping
for less than 7.5 hours a night may increase risk of heart disease and stroke and
death in people with high blood pressure, according to a new study released
The study of more than 1,200 Japanese men and women with
high blood pressure showed those who slept for less than 7.5 hours a night were
more likely to suffer a heart attack or stroke or die of cardiac arrest over a period
of 4 years compared to those who slept for a longer time.
Higher risk was particularly significant among short
sleepers who could not lower their blood pressure overnight, which normally
occurs, according to the report published in the Nov 10 2008 issue of the
Archives of Internal Medicine.
The results of the study suggest that doctors need to ask
their patients with high blood pressure about their sleep habits and advise
them to have sufficient sleep to avoid cardiovascular events.
Dr. Kazuo Eguchi M.D., Ph.D. of Jichi Medical University
in Tochigi, Japan, lead author of the study, said doctors should identify and
monitor people who are both short sleepers and can't have their blood pressure
The 50-month study was based on data from 1,255 men and
women aged 33 to 97 who had high blood pressure. They monitored each
participant's blood pressure changes over a 24 hour period using portable blood
During the study, 99 heart attacks, strokes or deaths
from cardiac arrest were recorded.
Overall, men and women who slept for less than 7.5 hours
a night were 68 percent more likely to have one of these cardiovascular events
than those who slept for longer periods.
"The incidence of cardiovascular disease was 2.4 per
100 person-years in subjects with less than 7.5 hours of sleep and 1.8 per 100
person-years in subjects with longer sleep duration," the authors wrote.
Those who had shown no decline in their blood pressure
overnight were at higher risk compared to those who had.
A much higher risk was found in those who both slept
insufficiently and had an overnight increase in blood pressure compared to
those with normal sleep duration plus no overnight increase in blood pressure.
These people were four times more likely to have heart attack, stroke, or death
from cardiac arrest.
Earlier chronic sleep deprivation has been already
associated with higher risk of a number of health problems such as diabetes,
coronary heart disease and obesity.
The researchers explained that insufficient sleep leads to
increased nervous system activity, which could stress the cardiovascular system
and no-dipping overnight blood pressure has been already linked to increased
nervous system activity during the day.
They concluded "shorter duration of sleep is a
predictor of incident cardiovascular disease in elderly individuals with
hypertension," particularly in those with elevated nighttime blood
pressure, the authors noted.
Sleep deprivation per se is likely to cause high blood
pressure, previous studies suggest.
An October 2007 study of 10,300 adults in the medical
journal Hypertension suggests that women age 35 to 55 who routinely sleep fewer
than seven hours a night may have an increased risk of developing high blood
Women who routinely slept for less
than five hours per night had a 31 percent higher risk compared to those who
slept more than 7 hours a day.
slept less than 6 hours per night were 42 percent more likely to have blood
Another study of 4,810 participants age 32 to 86
published in the May 2006 issue of hypertension suggests that long term sleep
deprivation increases the risk of hypertension.
Researchers found among participants age 32 to 59, those who slept for less
than six hours a night had more than double the risk of high blood pressure
than did those who slept for more than six hours per night.
Hypertension is the medical term for high blood pressure,
which by definition means blood level is 140/90 mmHg or higher.
In the United States, 73 million people age
20 and older have high blood pressure and the condition killed 54,707 people in
the country according to the American Heart Association.
Disclaimer: What's published on this website should be considered opinions of respective writers only and foodconsumer.org which has no political agenda nor commercial ambition may or may not endorse any opinion of any writer. No accuracy is guaranteed although writers are doing their best to provide accurate information only.
The information on this website should not be construed as medical advice and should not be used to replace professional services provided by qualified or licensed health care workers. The site serves only as a platform for writers and readers to share knowledge, experience, and information from the scientific community, organizations, government agencies and individuals.
Foodconsumer.org encourages readers who have had medical conditions to consult with licensed health care providers - conventional and or alternative medical practitioners.