Home blood pressure measurement had a stronger predictive power for mortality than did screening blood pressure measurement for a general population. This appears to be the first study in which the prognostic significances of home and screening blood pressure measurements have been compared.

Abstract-To investigate the association between cardiovascular mortality and short-term variabilities in blood pressure and heart rate, we performed a long-term prospective study of ambulatory blood pressure monitoring in Ohasama, Japan, starting in 1987. We obtained ambulatory blood pressure and heart rate in 1542 subjects Ն40 years of age. Blood pressure and heart rate variabilities were estimated as a standard deviation measured every 30 minutes by ambulatory monitoring. There were 67 cardiovascular deaths during the follow-up period (meanϭ8.5 years). The Cox proportional hazards model, adjusted for possible confounding factors, demonstrated a significant increase in cardiovascular mortality, with an increase in daytime systolic ambulatory blood pressure variability. A similar trend was observed in daytime diastolic and nighttime ambulatory blood pressures. Cardiovascular mortality rate increased linearly, with a decrease in daytime heart rate variability. Subjects in whom the daytime systolic ambulatory blood pressure variability was larger than third quintile and the daytime heart rate variability was lower than the meanϪSD were at extremely high risk of cardiovascular mortality. The blood pressure and heart rate variabilities obtained every 30 minutes by ambulatory blood pressure monitoring were independent predictors for cardiovascular mortality in the general population.

The ambulatory blood pressure had a stronger predictive power for mortality than did the screening blood pressure. This appears to have been the first study of the prognostic significance of ambulatory blood pressure monitoring versus screening blood pressure measurements in a general population.

The present study which prospectively investigated the relation between ambulatory blood pressure and first symptomatic stroke risk in a general population demonstrated that (i) ambulatory blood pressure values were linearly related to stroke risk; (ii) ambulatory blood pressures had the stronger predictive power for stroke risk than did screening blood pressure; and (iii) daytime blood pressure better related to stroke risk than did night-time blood pressure.

Abstract-Although reference values for ambulatory blood pressure (ABP) monitoring have been investigated in several population studies, these values were derived from cross-sectional observations and were based merely on the statistical distribution of blood pressure values. Therefore, we conducted a prospective cohort study to identify reference values for 24-hour ABP in relation to prognosis. We obtained measurements of 24-hour ABP for 1542 subjects (565 men) aged 40 years and over in a general population of a rural Japanese community and then followed-up their survival status. There were 117 deaths during the follow-up period (mean, 6.2 years). The association between baseline 24-hour ABP values and mortality, examined by the Cox proportional hazards regression model adjusted for possible confounding factors, showed a better fit with a second-degree equation than with a first-degree equation. On the basis of the results of this analysis, we identified the following reference values as the optimal blood pressure ranges that predict the best prognosis: 120 to 133 mm Hg for systolic blood pressure and 65 to 78 mm Hg for diastolic blood pressure. 24-Hour ABP values Ͼ134/79 mm Hg and Ͻ119/64 mm Hg were related to increased risks for cardiovascular and noncardiovascular mortality, respectively. This is the first report to propose reference values for 24-hour ABP based on a prognostic criterion. (Hypertension. 1998;32:255-259.)Key Words: blood pressure, ambulatory Ⅲ reference values Ⅲ mortality Ⅲ prospective studies Ⅲ Japanese population N oninvasive techniques for measuring ABP now make it possible to monitor blood pressure during activity and sleep and provide more reproducible information than casual (screening) blood pressure measurements.1-4 Target-organ damage and cardiovascular morbidity are more strongly correlated with ABP than with casual blood pressure. 3-12However, there is no consensus on the use of ABP to diagnose and manage hypertension, 3,4,[13][14][15][16][17] in part because reference values have not been established. Proposed reference values for ABPM are based on cross-sectional observations.18 -22 However, because the reference value must be the value that best predicts the risk of morbidity and mortality, a longitudinal study in a general population is needed to investigate the prognostic significance of the value.We initiated ABPM in the general population of a rural Japanese community 18 and have been monitoring the survival of these individuals since 1987. 23,24 The objective of the present study is to propose the reference values for 24-hour ABPM in relation to prognosis and to investigate the prognostic significance of the value. Methods DesignThe present report is based on a longitudinal observation of subjects who have been participating in an ABP measurement project in Ohasama, Iwate Prefecture, Japan, since 1987. The socioeconomic and demographic characteristics of this region and the details of the study project have been previously described. 18,23,24 The study protocol was approved ...