A new study finds that obstructive sleep apnea (OSA) may cause changes in blood vessel function, reducing blood supply to the heart in people who are otherwise healthy. Treatment with 26 weeks of continuous positive airway pressure (CPAP), however, improved the study participants’ blood supply and function. The findings appear in Hypertension: Journal of the American Heart Association.
Researchers looked for changes in blood vessel function in 108 participants who were otherwise healthy, with no differences in age, sex, body mass index, and smoking status. The participants were divided into three groups: 36 people with moderate or severe OSA without high blood pressure; 36 high blood pressure patients without OSA; and 36 patients with neither high blood pressure nor OSA. Researchers used myocardial contrast echocardiography to check the blood supply to the heart muscle, as well as several other techniques to assess blood vessel function.
While the patients in the control groups weren’t treated with CPAP therapy, all the OSA patients received CPAP therapy. The researchers recognize that proper randomization studies will still be needed to confirm this intervention’s beneficial effects on the blood vessels.
The study is the first to show blood vessel abnormalities in OSA patients. Previous studies have linked blood vessel dysfunction to cardiovascular disorders. Reversing blood vessel abnormalities could help patients with OSA who are otherwise healthy avoid developing and dying from cardiovascular disorders, according to the researchers.
“The findings should change how doctors treat patients with obstructive sleep apnea,” said Gregory Y. H. Lip, MD, lead author and professor of cardiovascular medicine at the University of Birmingham, United Kingdom. “Even apparently healthy patients with sleep apnea show abnormalities of small and large blood vessels, as well as impaired blood supply to the heart muscle, and these can improve with CPAP therapy.”