Heart Failure Patients
with Sleep Apnea Benefit by Drug
Researchers have found that heart failure patients with sleep apnea who
take a single dose of acetazolamide before going to bed exhibit less
sleep apnea, improved blood oxygen levels and fewer daytime symptoms of
sleepiness. Acetazolamide is a mild diuretic and respiratory stimulant.
This is important because many heart failure patients suffer from sleep
apnea or have been diagnosed with sleep apnea. Earlier studies have
shown a link between the two. Sleep apnea is a condition where the
sleeper stops breathing several times an hour while asleep.
There are two types of sleep apnea; central and obstructive. Younger
patients usually suffer from obstructive sleep apnea (OSA) while central
sleep apnea (CSA) usually occurs as we age. Recent research indicates
CSA is caused by loss of brain stem cells. Almost all people with sleep
apnea are unaware that they have the condition because it occurs while
they are asleep.
Shahrokh Javaheri, M.D., of the Pulmonary Service in the Department of
Veterans Affairs Medical Center and Department of Medicine, at the
University of Cincinnati College of Medicine in Cincinnati, Ohio,
conducted double blind placebo studies on 12 male patients with stable
heart failure who had more than 15 episodes per hour each night of sleep
apnea. The average age was 66.
In heart failure, the quantity of blood pumped each minute by the heart
is insufficient to meet the body’s requirements for oxygen and
nutrients. In the past, acetazolamide was use principally to help treat
breathing irregularities and sleep apneas occurring at high altitude.
The participants either took acetazolamide or the placebo for 6 nights.
There was a two-week washout period between treatments before the
patients switched regimens.
Each patient underwent a sleep test, an analysis of blood gases as well
as a pH study (a test of acidity or alkalinity in the blood), a
measurement of serum electrolytes, a pulmonary function test, plus other
measurements at the start of the study and at the completion of each arm
(acetazolamide and placebo).
Dr. Javaheri said "An important finding of the double-blind study was
the significant improvement in patient perception of improved sleep
quality, waking up more refreshed, with less daytime fatigue and
sleepiness while taking acetazolamide, compared with placebo."
"We hypothesize that with long-term drug therapy, as sleep-related
breathing disorders improve, it may be reflected in an improvement in
cardiac function that will further improve periodic breathing, resulting
in a positive feedback cycle," said Dr. Javaheri. "Improvement in sleep
apnea may assist cardiac function by a variety of mechanisms such as
Further long term tests are needed to measure patient cardiac function,
quality of life and the levels of norepinephrine in the plasma and
urine. Norepinephrine is a hormone used to maintain blood pressure and
to treat cardiac arrest.
The research appears in the second issue for January 2006 of the
American Journal of Respiratory and Critical Care Medicine, published by
the American Thoracic Society.
Best Syndication Staff Writer
help you Sleep
Keywords and misspellings: apnea apnia respironix resmed c-pap
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