Effects of anti-hypertensive treatment on major cardiovascular events in populations within prehypertensive levels: a systematic review and meta-analysis.

Uncertainties still remain in terms of the efficacy of anti-hypertensive treatment on the risk of major cardiovascular (CV) events within prehypertensive levels. This review aims to assess the efficacy and safety of anti-hypertensives on the CV risks in populations within prehypertensive levels. Randomized controlled trials (RCTs) concerning active treatment vs placebo in populations within prehypertensive levels were identified through electronic database and manual search. Outcomes included the first co-primary outcomes, stroke, heart failure (HF), myocardial infarction (MI), all-cause mortality, and cardiovascular mortality. The first co-primary outcomes were defined as composite cardiovascular disease (CVD) events in the included studies. A total of 29 RCTs involving 127,641 participants were identified. Pooled analysis showed active treatment was associated with a significant 7% reduction in risk of the first co-primary outcomes, 14% in stroke, and 10% in HF as compared to placebo (0.86, 0.77-0.96; 0.93, 0.89-0.98; and 0.90, 0.83-0.97). However, there were no significant reductions in risk of MI, all-cause mortality, and cardiovascular mortality. A significant reduction in risk of the first co-primary outcomes was observed in subpopulations with systolic blood pressure (SBP) 130-139 mmHg (0.94, 0.89-0.99) or prior CVDs (0.88, 0.82-0.94). Meta-regression analyses showed no significant relative risk reductions proportional to the magnitude of the mean baseline BP, mean on-treatment BP, the mean absolute change in BP, the proportion of patients with hypertension, and mean age. In summary, anti-hypertensive treatment has beneficial cardiovascular effects in populations within prehypertensive levels, especially in subpopulations with SBP 130-139 mmHg or prior CVDs.