In a study of patients with hypertension, those with resistant hypertension—meaning that their blood pressure remained elevated despite concurrent use of three antihypertensive agents of different classes—had a higher rate of sleep apnea (9.6%) than those without resistant hypertension (7.2%). Resistant hypertensive patients with sleep apnea had an increased risk of ischemic heart events and congestive heart failure compared with patients with sleep apnea and non-resistant hypertension. There were no differences in risk of stroke and premature death in patients with resistant versus non-resistant hypertension, however.

The study included 470,386 hypertensive individuals. Patients were identified from 2006 through 2010 and were followed until the end of 2010.

“Our study suggests that the risk for cardiovascular outcomes is increased in sleep apnea patients with resistant hypertension compared with those with non-resistant hypertension,” says Simran K. Bhandari, MD, lead author of the Respirology study, in a release.