The association of conventionally medicated systolic and diastolic blood pressure level and mortality from cardiovascular disease : is the lower the better in high stroke population?

概要

〔目的(Purpose)〕
The new American Heart Association guidelines suggest benefit for systolic blood pressure (SBP)<130 mmHg, diastolic blood pressure (DBP)<80 mmHg. It remains unclear whether this is also favorable for Asian and East-Europeans where, in contrast to Western countries, mortality from stroke has been higher than coronary heart disease (CHD).

〔方法ならびに成績(Methods/Results)〕
We performed a cohort of 10,061 individuals, between 1988-90 at baseline, who were on conventionally antihypertensive medication and without history of cardiovascular disease (CVD) or cancer, in Japan where recorded higher stroke mortality than CHD. The conventionally medicated SBP categorized into <130, 130-139, 140-149, 150-159, >160 mmHg. For DBP <70, 70- 79, 80-89, 90-99, >100 mmHg. To investigate the risk of stroke, CHD and total CVD mortality according to conventionally medicated SBP and DPB, the hazard ratios (HRs) and 95% confidence intervals (95% Cis) were calculated by competing risk analysis, using as reference SBP and DBP levels of <130 mmHg and <70 mmHg. During the 21 years of follow-up, 565 stroke, 275 CHD and 1,081 total CVD deaths were recorded. Conventionally medicated hypertensive patients with SBP<130 mmHg showed greater benefit with CHD mortality, but not for stroke. The nadir HR (95%CI) was 0.65 (0.80-0.91) at SBP of 130-139 mmHg and 0.81 (0.73-0.89) at DBP of 90-99 mmHg for stroke and total CVD mortality. While, lower DBP associated with stroke, CHD and total CVD morality.

〔総括(Conclusion)〕
These findings will provide better prevention for CVD, particularly for populations where the mortality from stroke has been higher than that from CHD, such as Asians and East-Europeans.