How Much Lowering of Blood Pressure Is Required to Prevent Cardiovascular Disease in Patients With and Without Previous Cardiovascular Disease?

Abstract

Purpose of review: To review the recent large-scale randomised evidence on pharmacologic reduction in blood pressure for the primary and secondary prevention of cardiovascular disease.

Recent findings: Based on findings of the meta-analysis of individual participant-level data from 48 randomised clinical trials and involving 344,716 participants with mean age of 65 years, the relative reduction in the risk of developing major cardiovascular events was proportional to the magnitude of achieved reduction in blood pressure. For each 5-mmHg reduction in systolic blood pressure, the risk of developing cardiovascular events fell by 10% (hazard ratio [HR] (95% confidence interval [CI], 0.90 [0.88 to 0.92]). When participants were stratified by their history of cardiovascular disease, the HRs (95% CI) in those with and without previous cardiovascular disease were 0.89 (0.86 to 0.92) and 0.91 (0.89 to 0.94), respectively, with no significant heterogeneity in these effects (adjusted P for interaction = 1.0). When these patient groups were further stratified by their baseline systolic blood pressure in increments of 10 mmHg from < 120 to ≥ 170 mmHg, there was no significant heterogeneity in the relative risk reduction across these categories in people with or without previous cardiovascular disease (adjusted P for interaction were 1.00 and 0.28, respectively). Pharmacologic lowering of blood pressure was effective in preventing major cardiovascular disease events both in people with or without previous cardiovascular disease, which was not modified by their baseline blood pressure level. Treatment effects were shown to be proportional to the intensity of blood pressure reduction, but even modest blood pressure reduction, on average, can lead to meaningful gains in the prevention of incident or recurrent cardiovascular disease.

Keywords: Anti-hypertensives; Cardiovascular diseases; Hypertension; Meta-analysis; Randomised controlled trials; Therapeutics.

Fig. 1

The effect of blood pressure–lowering drug treatment on the risk of major cardiovascular events [••]. HR, hazard ratio; CI, confidence interval. A Intensity of blood pressure reduction in relation to the relative treatment effects on the risk of major cardiovascular events. The centre of the bubbles indicates the HR for each trial, with the size of the bubble inversely proportional to the respective standard error. The solid red line is the fitted regression line; the dashed blue lines indicate 95% confidence interval; and the dashed grey line indicates HR = 1·0. *Excluding the first 12 months after randomisation. B Rates of major cardiovascular events per 5 mm Hg reduction in systolic blood pressure, stratified by treatment allocation and cardiovascular disease status at baseline. Major cardiovascular events consisted of fatal or non-fatal stroke, fatal or non-fatal myocardial infarction or ischaemic heart disease, or heart failure causing death or requiring admission to hospital

Fig. 2

Effects of blood pressure–lowering treatment on major cardiovascular disease events (fatal or non-fatal stroke, fatal or non-fatal myocardial infarction or ischaemic heart disease, or heart failure causing death or requiring admission to hospital), by cardiovascular disease status and systolic blood pressure (mmHg) level at baseline [••]. The Forest plot shows the hazard ratios (HR) and 95% confidence intervals (CI) per 5 mm Hg systolic blood pressure reduction. Adjusted p_interaction values were adjusted for multiple testing using Hommel’s method. Unadjusted p_interaction values were unadjusted for multiple testing