Treat Sleep Apnea, Lower Hard-to-Control BP?
Sleep apnea device allows normal breathing, reduces stress on body, study suggests
"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.