CFAH logoDiuretics are drugs that may be frequently recommended as a first-line treatment for high-blood pressure. A new study from the University of British Columbia claims that diuretics are also effectual when they may be added as a second agent to other blood-pressure lowering drugs.

Also, diuretics are said to be of use in spite of which blood pressure medication the patient is consuming.

Around 53 studies were examined by the experts led by Jenny Chen. These studies assessed diuretics in about 15,129 patients to see how much blood pressure reduces when patients consume a diuretic like Diuril, with a different anti hypertensive drug.

Medical professionals describe hypertension as a blood pressure measurement of equivalent to or more than 140/90 mmHg. Hypertension is believed to be a major contributor to heart disease, kidney disease and stroke.

Thiazide diuretics were claimed to be developed first in the 1950’s. They could be successful in controlling hypertension and are apparently one of the least costly medications among other ones for that purpose.

An average blood pressure of 156/101 mmHg was seen in the patients, at the start of the study. Most of them were white and their average age was supposedly 54 years. This examination lasted from 3 to 12 weeks, 6 weeks on average.

In almost all the examinations, hydrochlorothiazide was the diuretic which was used. Diuretics were added as a second medication to recent blood pressure lowering drugs like ACE inhibitors, ARBs and calcium channel blockers.

Thiazide diuretics apparently lowered blood pressure between 4/2 mmHg at lower doses and 14/6 mmHg at higher doses, when it was added as a second drug. These results supposedly did not rely on the class of first-line drug prescribed.

Chen mentioned, “The most important finding is that diuretics administered as a second-line drug lower blood pressure to the same degree as when given alone. Blood pressure reduction appears to be independent of the first-line drug used. The second most important finding is that the blood pressure lowering effect was greater with greater doses. This has not been demonstrated previously in clinical studies.”

Sandra Taler, M.D., a clinician in the division of nephrology and hypertension at the Mayo Clinic, commented, “For certain drugs — ACE inhibitors and ARBs — it’s generally been promoted that adding a diuretic will have a ‘synergistic effect. Adding a diuretic to these drugs should result in a greater reduction in blood pressure than just the single effect of each drug. This study did not find that, and it really didn’t matter what drug the diuretic was added to.”

Chen remarked, “Practice approaches have evolved so that providers are more likely to start a drug and not necessarily bring it up to a high dose, but start a second drug instead. They may also start a pill that has two different drugs in it.”

Taler is of the opinion that this approach may reduce side effects while maximizing the efficacy of every drug. Taler mentioned diuretics are a first-line option in patients with uncomplicated high blood pressure. Nevertheless, patients might have other medical problems like diabetes or heart failure that may make other blood pressure medications a superior first-line therapy.

The review appears in the latest issue of The Cochrane Library, a publication of The Cochrane Collaboration, an international organization that evaluates medical research.