Blood pressure, heart rate, and double product in a pooled cohort: The Japan Arteriosclerosis Longitudinal Study

Objective: To identify the characteristics of blood pressure (BP), heart rate (HR), and double product in a Japanese population sample. Methods: We pooled individual records from 1999 to 2005 for 111 007 participants in 25 community-based cohorts and seven worksite-based cohorts. The data were analyzed to provide information on BP, HR, and double product according to age-sex groups and use of antihypertensive medication. Results: Average BP was 130/77 mmHg among men and women combined. Among untreated individuals, SBP increased with age, whereas DBP reached a ceiling around the age of 60 years. The average SBP of treated participants was around 140 mmHg, irrespective of age, whereas DBP decreased linearly with age, and 56.4% of treated participants had a BP of 140/90 mmHg or over. HR did not differ across age groups or treatment status. The double product, also called the rate-pressure product, calculated by multiplying the SBP and the HR, increased with age among untreated individuals, whereas it first decreased and then increased with age among treated individuals. Conclusion: Based on these collaborative data, insufficient BP control in Japan, where the average life expectancy is the longest in the world, was seen.