Relative role of systolic, diastolic and pulse pressure as risk factors for cardiovascular events in the Brisighella Heart Study

OBJECTIVE The objective of this study was to determine the contribution of elevated blood pressure parameters to the long-term incidence of cardiovascular events. DESIGN A prospective, population-based longitudinal epidemiological cohort. SETTINGS The population of the town of Brisighella. PATIENTS The Brisighella Heart Study involved 2939 randomly selected residents of Brisighella, Italy aged 14 to 84 years, free of cardiovascular (CV) disease at enrolment and followed since 1972. Subjects were clinically evaluated at baseline and every 4 years following enrolment when extensive clinical and laboratory data were obtained in addition to the assessment of morbidity and mortality. MAIN OUTCOME MEASUREMENTS The Cox regression analysis, adjusted for the main risk factors for CV disease was used to determine the independent prognostic significance of systolic, (SBP), diastolic (DBP), and pulse pressure (PP). The events of interest were coronary heart disease (CHD) and cerebrovascular disease (CVD). RESULTS Adjusted hazard ratios (HRs) for combined CHD + CVD at SBP categories of 120–139, 140–159, and > 159 mmHg were 1.45 [95% confidence interval, (CI), P = 0.035], 1.88 (95% CI, P = 0.0008), and 2.31 (95% CI, P < 0.0001), respectively. For DBP ranges of 70–79, 80–89, and > 89 mmHg, HRs were 0.91 (95% CI, P = 0.677), 1.33 (95% CI, P = 0.169), and 1.65 (95% CI, P = 0.029), respectively. PP ranges from 54–67 and > 67 mmHg were associated with HRs of 1.23 (95% CI, P = 0.149), and 1.38 (95% CI, P = 0.030), respectively. Similar results were seen for CVD and CHD as separate endpoints. CONCLUSIONS The present study demonstrates that SBP is a stronger predictor of cardiovascular events than DBP in the Brisighella population. The added prognostic significance of PP is also demonstrated, particularly if PP exceeds 67 mmHg.