January 25th, 2011
New Study Finds Hydrochlorothiazide Inferior To All Other BP Drugs
At the dosages most often used, hydrochlorothiazide (HCTZ), the most widely used antihypertensive agent in the world, is “consistently inferior” to all other drugs, according to a new meta-analysis published in JACC. Franz Messerli and colleagues performed a systematic review of studies that compared HCTZ to other drugs using 24-hour ambulatory blood pressure monitoring and found that the decrease in blood pressure with HCTZ (6.5 mm Hg systolic and 4.5 mm Hg diastolic) was significantly less than with ACE inhibitors (12.9/7.7 mm Hg), ARBs (13.3/7.8 mm Hg), beta-blockers (11.2/8.5 mm Hg), and calcium channel blockers (11.0/8.1 mm Hg).
The authors note that HCTZ is as effective as the other antihypertensive agents when blood pressure is measured in the office. They write that this suggests that HCTZ is likely less effective at night. Although HCTZ is widely perceived to be clinically effective in improving outcomes, Messerli and colleagues write that “all outcome studies were done with higher doses than the currently used 12.5 to 25 mg or with other thiazides such as chlorthalidone or indapamide.”
However, because HCTZ is “suboptimal” as monotherapy, that “should not prevent it from being useful in combination with” other agents, since many studies have found that HCTZ in combination with other agents yields an incremental reduction in blood pressure.