BP drugs can be the culprit behind uncontrolled BP

According to the findings of a latest research, blood pressure pills, commonly prescribed to control blood pressure levels, can actually confer a negative effect. They raise blood pressure instead.

Tailor-made treatment for blood pressure required
The problem, however, can be corrected if physicians take note of blood levels of the enzyme renin. Based on the levels of enzyme renin physicians can select and administer drugs most suitable for their patients, researchers say.

Renin, also known as angiotensinogenase, is an enzyme that contributes in the body's renin-angiotensin system (RAS) – the system that mediates extracellular volume, and arterial vasoconstriction, thereby, regulating the body's mean arterial blood pressure.

"Our findings suggest that physicians should use renin levels to predict the most appropriate first drug for treating patients with hypertension," says lead author Michael Alderman, professor of epidemiology and population health and of medicine at Einstein.

Details of the study
The study, conducted by researchers at Albert Einstein College of Medicine of Yeshiva University, involved 945 patients, all of whom were participants in a workplace antihypertensive treatment program in New York City held between 1981 and 1998.

All participants had a systolic blood pressure of at least 140 mmHg at baseline. None were taking treatment for high blood pressure at the start of the study.

All participants were given a single antihypertensive medication, either a diuretic or a calcium channel blocker, called the "V" drugs, which help lower blood volume, or a beta blocker or an ACE inhibitor, the "R" drugs, which help lower the levels of renin.

Plasma renin activity (PRA) and systolic blood pressure readings were measured for all participants. Subsequently, systolic blood pressure readings were again recorded every one to three months of treatment.

The renin levels helped pick up patients who were most likely to respond favorably to either an R or a V drug.

The renin test also helped in identifying patients who would most likely experience a "pressor response"— an increase of 10 mmHg or more in the systolic blood pressure readings.

Overall, 7.7 percent of the participants experienced a "pressor response," researchers found.

Two groups of patients might specifically benefit from renin testing, Alderman said, one being the patients prescribed antihypertensive drugs for the first time, and two, the patients who are taking multiple antihypertensive drugs.

"With renin testing, you will more often get blood pressure under control with less therapy," he added.

The findings of the study are published in the online edition of the 'American Journal of Hypertension.'