How the Times Have Changed: Antihypertensive Agents
This Editorial is a personal reflection on an article from the Consultant archives.
Michael J. Bloch, MD
Renown Institute for Heart and Vascular Health
Bloch MJ. How the times have changed: antihypertensive agents [published online February 18, 2020]. Cardiology Consultant.
Mailloux LU. Hypertension: proper use of the laboratory to monitor drug therapy. Consultant. 1985;25(10):75-85. https://www.consultant360.com/article/cardiology/hypertension-proper-use-laboratory-monitor-drug-therapy.
In reviewing this article from the archive, I was actually struck by how little our pharmacopeia of antihypertensives has changed—not just since I have been involved in the field but even since I graduated high school at the time this article was published 35 years ago. I certainly have changed a lot since then, but our available classes of antihypertensives actually have not changed much. Of course, there are a few notable exceptions. We now have an entirely new class of antihypertensives available to us, the angiotensin receptor blockers (ARBs), that are essentially free of the type of adverse effects highlighted in this article. But our newer antihypertensive agents, including ARBs, the direct renin inhibitor aliskiren, and the novel β-blocker nebivolol, are really just variations of old themes.
Perhaps the lack of innovation in the pharmacological approach to hypertension should not be surprising. After all, the essential pathophysiology of hypertension, which involves the mediation of volume, the renin-angiotensin system, and the sympathetic nervous system, remains constant. And, in many ways this lack of new classes of antihypertensive agents really speaks to the tremendous success we have seen with the agents that we already have available to us. Focusing on angiotensin-converting enzyme (ACE) inhibitors, thiazide diuretics, and calcium channel blockers, we see tremendous proven efficacy—not just in lowering blood pressure but also in reducing cardiovascular events, with a low risk of adverse events and widespread access due to generic-pricing pressure.
Notwithstanding the important potential adverse events that are highlighted in this archived article, available antihypertensive medications are very well tolerated in general, especially when used in combination at low dose. And, the availability of multiple different classes allows us to easily switch to a different class of medications in the rare instance that the patient has adverse effects or conditions that prevent the use of any 1 of these agents.
Quite frankly, what is really striking is that despite this tremendous armamentarium of pharmacologic agents, our overall blood pressure control rates in the United States, and around the world, remain disturbingly low. Here in the United States, control rates have hovered around 50% for the last decade, despite increasing access and decreasing prices of blood-pressure-lowering agents. This suboptimal blood pressure control leaves tens of millions of Americans at increased risk of cardiovascular events like myocardial infarction, stroke, and heart failure.
In thinking about this article and the public health shortcomings of hypertension control rates, I realized that we need to move past the era when we focused on the benefits and risks of individual antihypertensive agents. Instead, we need to find better ways to motivate clinicians to take action to intensify treatment in the setting of poorly controlled blood pressure, and we need to better motivate patients to be more adherent with prescribed therapy. We also need improved public health campaigns so that our citizens better understand the risks of poorly controlled hypertension and the tremendous impacts that available, well-tolerated antihypertensives prescribed in addition to lifestyle modification can have on their cardiovascular risk and subsequent quality of life.
Given documented issues we see with adherence to antihypertensive medications, there is increasing interest in looking toward the potential of device therapy for the treatment of hypertension, particularly among patients who have been treated but are not controlled and are averse to increasing medication burden. The advantage of these “always on” devices, like renal denervation therapy, will of course need to be balanced by their potential costs and need to undergo the vigorous scrutiny for adverse effects that our current and hypertensive medications have already undergone.
Michael J. Bloch, MD, is an associate professor at the University of Nevada School of Medicine, medical director of Renown Vascular Care at the Renown Institute for Heart and Vascular Health, and president of Blue Spruce Medical Consultants, PLLC, in Reno, Nevada.