Black people are more likely to have hypertension than their white counterparts. Now, new findings published in the journal Circulation suggest that untreated sleep apnea that’s moderate or severe is associated with increased odds of resistant hypertension in African Americans, according to an article by American Heart Association News.

Sleep apnea is a serious sleep disorder that occurs when a person’s breathing stops and starts repeatedly during sleep. Caused by the muscles of the throat relaxing intermittently and blocking an individual’s airway, the problem is commonly managed by a continuous positive airway pressure (CPAP), a machine that delivers air pressure through a mask during sleep.

Resistant hypertension is blood pressure that remains elevated despite the use of three or more types of antihypertensive meds.

To further examine the already established link between sleep apnea and hypertension, instead of evaluating self-reported data, researchers used objective sleep testing equipment to check Black adults in the study.

Results showed that an estimated 94 percent of Black adults in the study with obstructive sleep apnea (OSA) weren’t diagnosed or treated for the condition. In addition, scientists found that almost half of these participants had uncontrolled high blood pressure and 14 percent had resistant hypertension compared with 9 percent of U.S. adults overall.

“This should raise awareness of the need to screen African Americans for sleep apnea as a possible way to get control of hypertension,” said Dayna Johnson, PhD, MPH, an assistant professor at Emory University in Atlanta, who led the study that took place at the division of sleep and circadian disorders at Boston’s Brigham and Women’s Hospital.

These findings add to research that connects moderate or severe sleep apnea with high blood pressure. “The part I didn’t expect was that the association (with sleep apnea) was mainly found among those with hard-to-treat hypertension but not among those [with] milder forms of uncontrolled hypertension,” Johnson added.

Experts believe the results of this study might prompt health care providers to try new treatments for hypertension. But others stress that more research will be necessary to establish a cause-and-effect relationship between OSA and resistant hypertension, which can lead to strokes, heart attacks and kidney disease.

Click here to learn how snoring and sleep apnea are linked to a greater risker for heart damage in women.