Sleeping Less than 7.5 Hours Daily May Cause Heart
Disease for Elderly with Hypertension
Particularly when it occurs with elevated nighttime
blood pressure; sleep patterns should be checked for those with high
blood pressure
Nov. 12, 2008 - Sleeping less than seven and a half
hours per day may be associated with future risk of heart disease for
older people,
according to a report in the November 10 issue of Archives of Internal
Medicine, one of the JAMA/Archives journals.
In addition, a combination
of little sleep and overnight elevated blood pressure appears to be
associated with an increased risk of the disease.
Getting adequate sleep is essential to preventing
health conditions such as obesity and diabetes as well as several risk
factors for cardiovascular disease including sleep-disordered breathing
and night-time hypertension (high blood pressure).
But, the evidence has been growing that changes in
modern lifestyle are causing people to get less sleep.
This study, by Kazuo Eguchi, M.D., Ph.D., at Jichi
Medical University, Tochigi, Japan, and colleagues, monitored the sleep
of 1,255 individuals with hypertension (94%) and followed them for an
average of 50 months.
Their average age was 70.4 years with a range of 33
to 97 years; there were 476 men and 779 women.
Researchers noted patients' sleep duration, daytime
and nighttime blood pressure and cardiovascular disease events such as
stroke, heart attack and sudden cardiac death.
During follow-up, 99 cardiovascular disease events
occurred.
Sleep duration of less than 7.5 hours was
associated with incident cardiovascular disease.
"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 write.
Patients with shorter sleep duration, plus an
overnight increase in blood pressure, had a higher incidence of heart
disease than those with normal sleep duration plus no overnight increase
in blood pressure.
But, the occurrence of cardiovascular disease in
those with a longer sleep duration, versus those with a shorter sleep
duration, was similar in those who did not experience an overnight
elevation in blood pressure.
"In conclusion, shorter duration of sleep is a
predictor of incident cardiovascular disease in elderly individuals with
hypertension," particularly when it occurs with elevated nighttime blood
pressure, the authors note. "Physicians should inquire about sleep
duration in the risk assessment of patients with hypertension."
Editor's Note: This study was supported in part by
grants-in-aid from the Foundation for the Development of the Community,
Tochigi, Japan; the Banyu Fellowship Program, sponsored by Banyu Life
Science Foundation International; and the National Heart, Lung and Blood
Institute.
Nov. 12, 2008 - Sleeping less than seven and a half
hours per day may be associated with future risk of heart disease for
older people,
according to a report in the November 10 issue of Archives of Internal
Medicine, one of the JAMA/Archives journals. 
