Prognostic impact of sex–ambulatory blood pressure interactions in 10 cohorts of 17 312 patients diagnosed with hypertension

BACKGROUND: Whether ambulatory blood pressure (BP) among hypertensive patients better predicts cardiovascular events (CVEs) in women relative to men is unclear. METHODS: We searched PUBMED and OVID databases. Cohorts were required to have hypertension, 1+ years of follow-up, with stroke and coronary artery disease as outcomes. Lead investigators for these cohorts provided ad hoc analyses. Random-effect meta-analyses gave hazard ratios for CVEs from a 1 standard deviation (SD) mmHg increase and a 10 mmHg increase in SBP. Subgroup and meta-regression analyses quantified the relative increase in risk in women versus men. RESULTS: Patients were from Europe, Brazil, and Japan (10 cohorts, n = 17 312, CVEs = 1892). One cohort lacked sex-specific hazard ratios from 24 h and clinic SBP. Compared with men, women tended to have greater SDs and coefficients of variation of SBP. Subgroup analyses showed higher hazard ratios in women than in men from increases in ambulatory but not clinic SBPs. For women relative to men, a 1 SD increase in night-time, daytime, 24 h, and clinic SBP gave hazard ratios (95% confidence limits) of 1.17 (1.06-1.30), 1.24 (1.10-1.39), 1.21 (1.08-1.36), and 0.94 (0.84-1.05), respectively, whereas a 10 mmHg increase in SBP, gave hazard ratios of 1.06 (0.99-1.14), 1.13 (1.03-1.23), 1.10 (1.01-1.21), and 0.96 (0.89-1.03), respectively. CONCLUSION: In patients with hypertension, increases in ambulatory, but not clinic, SBP predict higher risks for CVEs in women than in men. Although women tended to have greater variability in SBP, this did not entirely explain the sex-ambulatory BP interactions.