Prehypertension and risk of cardiovascular diseases: a meta-analysis of 47 cohort studies

Objective: To assess the association of prehypertension (SBP 120-139 mmHg and/or DBP 80-89 mmHg) and total cardiovascular diseases (CVDs), coronary heart disease (CHD), myocardial infarction (MI), and stroke. Methods: PubMed, Embase, and Web of Science were searched for articles published up to 7 November 2018. Normal range BP was considered SBP less than 120 mmHg and DBP less than 80 mmHg. RRs and 95% Cls were pooled using fixed-effects models. Meta-regression was conducted to estimate the heterogeneity among subgroups. Results: We included 27 articles (47 studies including 491 666 study participants) in the analysis. Prehypertension was associated with total CVDs (RR 1.40, 95% CI 1.34-1.46), CHD (1.40, 1.28-1.52), MI (1.86, 1.50-2.32), and stroke (1.66, 1.56-1.76). Risk of total CVDs, MI, and stroke was increased with low-range prehypertension (low-range: SBP 120-129 mmHg and/or DBP 80-84 mmHg) versus normal BP - RR 1.42 (95% CI 1.29-1.55), 1.43 (1.10-1.86), and 1.52 (1.27-1.81), respectively - and risk of total CVDs, CHD, MI, and stroke was increased with high-range prehypertension (high-range: SBP 130-139 mmHg and/or DBP 85-89 mmHg) - RR 1.81 (95% CI 1.56-2.10), 1.65 (1.13-2.39), 1.99 (1.59-2.50), and 1.99 (1.68-2.36), respectively. The population-attributable risk for the association of total CVDs, CHD, MI, and stroke with prehypertension was 12.09, 13.26, 24.60, and 19.15%, respectively. Conclusion: Prehypertension, particularly high-range, is associated with increased risk of total CVD5, CHD, MI, and stroke. Effective control of prehypertension could prevent more than 10% of CVD cases.