Four Blood Pressure Indexes and the Risk of Stroke and Myocardial Infarction in Japanese Men and Women

Abstract
Background— Information has been sparse on the comparison of 4 blood pressure (BP) indexes (systolic BP [SBP], diastolic BP, pulse pressure, and mean BP [MBP]) in relation to long-term incidence of stroke and myocardial infarction, particularly in middle-aged and older Asians. Methods and Results— The Japan Arteriosclerosis Longitudinal Study Group conducted a meta-analysis of 16 cohort studies in Japan. A total of 48 224 men and women 40 to 89 years of age participated at baseline, and 1231 stroke events and 220 myocardial infarction events occurred during an average 8.4-year follow-up. Multivariate-adjusted hazard ratios with a 1-SD higher value for each BP index were determined by Poisson regression. Analyses were also done in 4 age-sex groups. All 4 BP indexes were significantly related to all stroke risk. Stroke risk was most strongly related to MBP and SBP in both sexes and most weakly related to pulse pressure. Both stroke subtypes, ischemic and hemorrhagic, were most strongly related to MBP and SBP in both sexes. In addition, in men and women 70 to 89 years of age, MBP or SBP showed the strongest relation to all stroke risk. Myocardial infarction risk was most strongly related to SBP or MBP in both sexes. For any end points in any age-sex groups, pulse pressure was not the strongest predictor. Conclusions— The long-term incident risk of stroke and myocardial infarction associated with high BP in East Asian populations should be assessed mainly on the basis of SBP. MBP also may be an important predictor, but pulse pressure is a less important predictor for cardiovascular disease risk.