[Comparative study of blood pressure variability in the elderly in Kahoku and in Yaku]

A comparative community-based study of blood pressure (BP) variability in the elderly was carried out in the Japanese rural towns of Kahoku and Yaku. The prevalence of hypertension, orthostatic hypotension and use of antihypertensive drugs, effects of postute on BP and the "white coat" effect in BP were examined in each town. There was no difference in the prevalence of hypertension between in the two towns. Orthostatic increase in BP and pulse rate was more common in elderly females than in elderly males in both towns, indicating that standing itself was a load for subjects and activated sympathetic nervous tone in the female elderly. The prevalence of orthostatic hypotension was 8.5% and 12% in Kahoku and Yaku respectively, and the "white coat" effect on BP was demonstrated in the elderly in each town. In conclusion, we should take orthostatic change and the "white coat" effect into consideration in the evaluation of BP among the elderly.