Patients are diagnosed with resistant hypertension when they need three or more medications to treat high blood pressure but still have blood pressure that exceeds the goal for hypertension established in 2017 in the American Heart Association/American College of Cardiology guideline for hypertension. In addition, patients whose blood pressure achieves target values on four or more different types of blood pressure lowering medication are also considered to have resistant hypertension.
The 2017 guideline specifies blood pressure below 130 millimeters of mercury (mmHg) for the top number or 80 mmHg for the bottom number as the goal. Resistant hypertension is more often found among African-Americans, men, older adults and, people who are obese, or those who have diabetes, peripheral artery disease, obstructive sleep apnea or other conditions.
“Because several conditions can mimic resistant hypertension, a correct diagnosis is essential so as not to over medicate. Asking a patient who has previously been prescribed blood pressure lowering drugs whether they take them correctly is a good place to start, because not taking medications properly will result in poorly controlled blood pressure that could appear to be resistant hypertension,” said Robert M. Carey, M.D., chair of the statement writing group and professor of medicine at the University of Virginia Health Sciences Center.
The statement notes that 50 percent to 80 percent of people who should be taking blood pressure lowering medications don’t take them correctly because the regimen may be expensive and have unwanted side effects, which can result it poorly controlled blood pressure.