Patients with coronary artery disease plus treatment-resistant high blood pressure are at great risk.
Researchers warn that patients with heart disease combined with treatment-resistant hypertension are at greater risk of adverse cardiovascular events, including mortality.
While efforts have focused on lowering the surrogate endpoint of blood pressure (predictors of cardiovascular risk), the researchers said there has been little focus on reducing “hard cardiovascular endpoints” ― endpoints that are well defined and can be measured without observer judgement. However, they added that it is not known “whether or not intensive lipid lowering is beneficial for reducing the risk of cardiovascular events in this high-risk cohort.”
For the study, a team of U.S. scientists analyzed the Treating to New Targets (TNT) trial. TNT was designed to provide more information on the optimal level of LDL cholesterol (the ‘bad’ cholesterol that can cause atherosclerosis) for cardiovascular risk reduction in patients with established coronary heart disease. They found that among the 10,001 TNT participants, treatment-resistant hypertension was most likely to occur in those who were older, female, of Black race, had an increased body mass index, or had comorbidities such as diabetes, kidney disease, and previous myocardial infarction.
Lead researcher Dr. Sripal Bangalore, Assistant Professor, New York University School of Medicine, said these findings “emphasize the need to monitor these high-risk groups of patients carefully.”
The American Heart Association defines treatment-resistant hypertension as blood pressure that remains above goal in spite of the concurrent use of three antihypertensive agents of different classes. For the purposes of their study, the research team defined it as systolic blood pressure of at least 140 mmHg despite being on three antihypertensive medications, or less than140 mmHg on four or more medications.
All the TNT participants had coronary artery disease (CAD) and LDL cholesterol levels of under 130 mg/dL ― people in the U.S. at very high risk of heart disease, should have levels under 70 mg/dL. Of the participants, 11.1 percent also had treatment-resistant hypertension. About two-thirds met the first definition and a third the second definition.
During an average follow-up of 4.9 years, patients with treatment-resistant hypertension were a significant 17.2 percent more likely than those without (8.9 percent) to have a major cardiovascular event. The increased risk was present for patients with treatment-resistant hypertension by both definitions.
The increase was driven by elevated rates of coronary heart disease death, at 4.8 percent versus 2 percent, and nonfatal myocardial infarction, at 9.6 percent versus 5 percent. Rates of stroke and resuscitated cardiac arrest did not significantly differ between the groups, although both were statistically more common among patients with treatment-resistant hypertension.
They concluded that in patients with coronary artery disease, apparent treatment-resistant hypertension is associated with “a marked increase in the risk of cardiovascular morbidity and mortality, including an increase in all-cause death.”