True Resistant Hypertension Is Prevalent Worldwide

DUBAI, United Arab Emirates—True resistance and pseudoresistance to therapy are both commonly seen in patients treated for hypertension, a meta-analysis incorporating about 3.1 million people shows.

A look at studies from various parts of the world estimated the prevalence of either condition to be 10.3%, with patients who have chronic kidney disease—including those who have undergone renal transplantation—carrying the heaviest burden, Jean Jacques Noubiap, MD (University of Cape Town and Groote Schuur Hospital, South Africa), reported here at the 2018 World Congress of Cardiology & Cardiovascular Health.

“We really need to do something about that,” Noubiap told TCTMD. “We need to look for new medications and new procedures to treat patients with resistant hypertension.”

Noubiap said the future of treating resistant hypertension probably lies in procedures like renal denervation, which has been slowly making a comeback after the SYMPLICTY HTN-3 trial failed to show the superiority of denervation over a sham procedure back in 2014. Just this week, a US Food and Drug Administration advisory panel met to discuss the way forward for future trials of device-based therapies for hypertension.

The importance of finding new ways to treat hypertension is underscored by the scope of the problem: hypertension affects more than 1 billion people globally, Noubiap said. He added that control of high blood pressure is poor in all countries, but particularly so in African nations.

It’s very important that we think about simplifying the treatment regimens to improve compliance to treatment. Jean Jacques Noubiap

Noubiap and colleagues set out to estimate the global prevalence of particularly hard-to-treat cases of hypertension, pooling data from 64 studies involving about 3.1 million patients treated for the disease.

Resistant hypertension was defined as lack of control on at least three medications, including a diuretic, at optimal doses or on four or more medications for high blood pressure.

Apparent resistant hypertension (when pseudoresistant hypertension could not be ruled out) was found in a total of 14.7% of patients in the general hypertensive population, whereas pseudoresistant hypertension (when other modifiable factors such as medication adherence might be complicating treatment) was seen in 10.3%, with substantial heterogeneity across studies included in the meta-analysis.

True resistant hypertension was also found in 10.3% overall, varying widely across studies from 1.2% to 25.5% but remaining consistent across global regions. When looking at patient subsets, prevalence was lowest in obese patients (4.9%) and the elderly (12.3%) and highest in those with chronic kidney disease (22.9%) and renal transplant recipients (56.0%).

Patients with true resistant hypertension “are at very high risk of having a stroke or having a myocardial infarction,” Noubiap said, adding, “Our data highlight the importance of investigating causes of secondary hypertension in patients who have suspected resistant hypertension.”

The high prevalence of pseudoresistant hypertension underscores the need to exclude possible reasons for high blood pressure beyond true resistance, such as use of other types of medications that might increase blood pressure or lack of compliance with antihypertensive regimens, Noubiap said.

“Because compliance with medication is a big problem worldwide,” he said, “it’s very important that we think about simplifying the treatment regimens to improve compliance to treatment.”

Out-of-office measurements of blood pressure, such as 24-hour ambulatory BP monitoring or home BP readings, should be employed on a wider basis to exclude cases of pseudoresistant hypertension and clearly identify patients with true resistance, Noubiap said. He acknowledged, however, that that could be a challenge in low-income countries.