To examine whether blood pressure (BP), a major risk factor of cardiovascular disease, can be controlled in the elderly as well as in middle-aged persons, we analyzed the data of observational studies on trends for BP and cardiovascular disease incidence in a northeast rural community of Japan. This community was the subject of an ongoing hypertension control program that was initiated in 1963. A significant decline in BP levels was noted in each sex-age group between 1963 and 1966 and 1987 and 1991. The decline was greater in older persons compared with younger individuals. The BP decline was attributable to an increase in antihypertensive medication use, beginning in the 1970s. We compared BP levels of untreated offspring and parents when both were 40 to 49 years old. Blood pressure levels were significantly lower in the offspring than in parents. This result and the large downward shift of BP distribution in the second decade of follow-up suggested that the improvements in diets and other environmental factors contributed to the BP decline. Between 1964 and 1968 and 1989 and 1992, stroke incidence declined 70% to 79% for all sex and age groups (40-69 and greater than 70 years). The number of totally dependent stroke patients decreased in both the middle-aged and the elderly between 1976 and 1991. The decline in stroke mortality tended to be larger in the surveyed community than in adjacent communities. These results indicated that hypertension control is effective in preventing stroke in the elderly as well as in the middle-aged.