Predictive value for mortality of the double product at rest obtained by home blood pressure measurement: The ohasama study

Background To clarify whether the double product (DP) (product of systolic blood pressure (SBP) and pulse rate (PR)) at rest based on home blood pressure (HBP) measurement has prognostic value for mortality. Methods HBP data of 2,583 participants from a Japanese general population (40% men) ≥35 years of age (mean, 59 years) without a history of cardiovascular disease (CVD) were obtained. The prognostic significance for a 1,000 mm Hg × beats/min elevation in the DP was determined by Cox proportional hazard regression analysis. The association between mortality and the DP was compared to that between mortality and the SBP or the PR using the likelihood ratio (LR) test. Results During a mean follow-up of 12.0 years, 454 total deaths, 153 CVD deaths (85 cardiac diseases, 68 strokes), and 301 non-CVD deaths occurred. The DP was positively and significantly associated with total, CVD, cardiac, stroke, and non-CVD mortality. The LR test showed that the DP was more strongly associated with total mortality, mortality from cardiac disease, and non-CVD than SBP. Similarly, the DP was more strongly associated with total death, CVD death, and death from stroke than PR. Conclusions The home DP was significantly associated with mortality, and the LR test indicated that the association between the DP and mortality would be stronger than that between mortality and SBP or PR. These findings are preliminary, and further study is needed to confirm the usefulness of the DP in risk stratification.