By Steven Reinberg
HealthDay Reporter
TUESDAY, Dec. 10 (HealthDay News) — People with sleep apnea and
hard-to-control high blood pressure may see their blood pressure drop if
they treat the sleep disorder, Spanish researchers report.
Continuous positive airway pressure (
CPAP) is the standard treatment
for sleep apnea, a condition characterized by disrupted breathing during
sleep. The sleep disorder has been linked to high blood pressure.
Patients in this study were taking three or more drugs to lower their
blood pressure, in addition to having sleep apnea. Participants who
used the
CPAP device for 12 weeks reduced their diastolic blood pressure
(the bottom number in a blood pressure reading) and improved their
overall nighttime blood pressure, the researchers found.
“The prevalence of sleep apnea in patients with resistant [high blood
pressure] is very high,” said lead researcher Dr. Miguel-Angel
Martinez-Garcia, from the Polytechnic University Hospital in Valencia.
“This [sleep apnea] treatment increases the probability of recovering the normal nocturnal blood pressure pattern,” he said. Patients with resistant high blood pressure should undergo a sleep
study to rule out obstructive sleep apnea, Martinez-Garcia said. “If the
patient has sleep apnea, he should be treated with
CPAP and undergo
blood pressure monitoring.”
The report, published in the Dec. 11 issue of the
Journal of the American Medical Association, was partly funded by Philips-Respironics, maker of the
CPAP system used in the study.
The
CPAP system consists of a motor that pushes air through a tube
connected to a mask that fits over the patient’s mouth and nose. The
device keeps the airway from closing, and thus allows continuous sleep.
Sleep apnea is a common disorder. The pauses in breathing that
patients experience can last from a few seconds to minutes and they can
occur 30 times or more an hour.
As a result, sleep quality is poor, making sleep apnea a leading
cause of excessive daytime sleepiness, according to the U.S. National
Heart, Lung, and Blood Institute.
Dr. Gregg Fonarow, a spokesman for the American Heart Association and
professor of cardiology at the University of California, Los Angeles,
agrees that most patients with hard-to-control high blood pressure also
suffer from sleep apnea.
“Close to three out of four patients with resistant [high blood
pressure] have been found to have obstructive sleep apnea, and this
sleep apnea may contribute to the difficulty to control the blood
pressure in these patients,” he said.
Although this study showed a benefit from
CPAP in controlling blood
pressure, questions remain about the treatment’s overall effectiveness,
Fonarow said.
“Whether these improvements in blood pressure can be sustained in the
long term and will translate to improved health outcomes will require
additional studies,” he said. According to the chief medical liaison for Philips Respironics, Dr.
Teofilo Lee-Chiong, the
CPAP device allows the patient to sleep, and
thus lets the blood pressure drop normally as it would at night.
“Patients have to get used to it, and most patients do,” said
Lee-Chiong, who is also a professor of medicine at National Jewish
Health at the University of Colorado Denver.
The sound of the device is akin to a fan and can be lessened by placing the device under the bed or using earplugs, he added.
The cost of
CPAP machines vary but can range from a few hundred
dollars to $1,000, Lee-Chiong said.
CPAP is covered by most insurance,
including Medicare, he noted.
For the study, Martinez-Garcia and colleagues randomly assigned 194
patients with sleep apnea and high blood pressure to
CPAP or no
CPAP.
During the study the patients continued to take their blood pressure
medications.
The researchers found that those receiving
CPAP lowered their 24-hour
average blood pressure 3.1 mm Hg more than those not receiving
CPAP.
In addition, those treated with
CPAP had a 3.2 mm Hg greater reduction in 24-hour average diastolic blood pressure.
The difference in systolic pressure wasn’t statistically significant between the two treatment groups, the researchers noted.
Over the 12 weeks of the study, about 36 percent of those receiving
CPAP had at least a 10 percent drop in nighttime blood pressure,
compared with 22 percent of patients not receiving
CPAP, they added.
The systolic pressure, the top number, measures the pressure in the
arteries when the heart beats. The diastolic pressure, the bottom
number, measures the pressure in the arteries between beats.
More information
For more information on sleep apnea, visit the
U.S. National Heart, Lung, and Blood Institute.
Resources:
http://news.health.com/2013/12/10/treating-sleep-apnea-may-lower-hard-to-control-blood-pressure/