Should We Routinely Measure Renin Levels to Diagnose and Treat Patients With Hypertension? (Part I)

The Argument For

Phyllis August, MD, MPH

In This Article


The validity as well as the usefulness of measuring components of the renin-angiotensin-aldosterone system in the diagnosis and treatment of patients with elevated blood pressure (BP) has been debated for many years. Advocates of measuring plasma renin activity argue that this approach leads to individualized treatment, which is more likely to lower BP in a timely manner with fewer drugs.[1] Additionally, curable forms of secondary hypertension will be identified earlier. Opponents argue that tailoring antihypertensive therapy based on renin sodium profiling, compared with a conventional approach to treatment, has never been demonstrated to lead to improved clinical outcomes such as reduction in stroke, coronary artery disease, and cardiovascular mortality.[2] Both arguments clearly have merit, and I propose a reasonable approach to using the renin sodium profile based on available data. I also support the idea of further clinical investigation of the use of renin profiling to better establish its utility.

It is worth emphasizing some widely publicized, yet nevertheless disheartening, facts regarding treatment of hypertension. Hypertension is the most treatable and prevalent risk factor for cardiovascular disease. It has been more than adequately demonstrated that lowering BP reduces cardiovascular morbidity and mortality. Nevertheless, only 36% of patients with hypertension have adequately controlled BP.[2] There remain some major unresolved issues regarding the treatment of hypertension. For example, the optimum BP treatment targets have not been adequately identified. Although the cumulative evidence suggests that the most important determinant of cardiovascular outcome in patients with hypertension is achieving lower BP, there is a large body of reasonably persuasive evidence that specific antihypertensive agents may have benefits beyond BP lowering. Considerable resources have been consumed in an attempt to determine the ideal approach to initial treatment of hypertension, despite the realization that to achieve BP targets, many, if not most, patients will require more than one drug, thus diminishing the importance of this question.

The treatment of the individual patient with hypertension is not as straightforward as implied by guidelines. Patients with hypertension may present to the physician with a variety of different situations, making application of guidelines less helpful. For example, patients may present untreated with newly diagnosed hypertension -- the easiest scenario to deal with. They may present with inadequately controlled BP on one or more drugs, in which case the physician must decide whether to add additional medication or to switch from one drug to another. Patients may present with resistant hypertension on multiple drugs, or they may present with intolerable adverse effects of therapy. Each of these scenarios presents unique challenges.