Thiazide diuretics are recommended as first-line therapy for hypertension and are among the most commonly prescribed drugs worldwide.
According to their molecular structure, thiazide diuretics can be divided in thiazide-type ( TT ) and thiazide-like ( TL ) diuretics.
Thiazide-like diuretics have a longer elimination half-life compared with thiazide-type diuretics and have been shown to exert additional pharmacological effects, which may differently affect cardiovascular risk.
In a meta-analysis, researchers compared the effects of thiazide-type and thiazide-like diuretics on cardiovascular events and mortality. Randomized, controlled studies in adult hypertensive patients that compared thiazide-type or thiazide-like diuretics with placebo or antihypertensive drugs and had greater than or equal to 1 year follow-up were included.
Primary outcome was cardiovascular events; secondary outcomes included coronary events, heart failure, cerebrovascular events, and all-cause mortality.
Meta-regression analysis was used to identify confounders and correct for the achieved blood pressure reductions.
Twenty-one studies with more than 480 000 patient-years were included.
Outcomes were not affected by heterogeneity in age, sex, and ethnicity among included studies, whereas larger blood pressure reductions were significantly associated with increased risk reductions for all outcomes ( P less than 0.001 ).
Corrected for differences in office blood pressure reductions among trials, thiazide-like diuretics resulted in a 12% additional risk reduction for cardiovascular events ( P=0.049 ) and a 21% additional risk reduction for heart failure ( P=0.023 ) when compared with thiazide-type diuretics.
The incidence of adverse events was comparable among thiazide-type, thiazide-like diuretics, and other antihypertensive therapy.
The data suggest that the best available evidence seems to favor thiazide-like diuretics as the drug of choice when thiazide treatment is considered for hypertension. ( Xagena )
Olde Engberink RH et al, Hypertension. 2015; Epub ahead of print