Prognosis and outcome of elderly hypertensives in a Japanese community: results from a long-term prospective study.

A long-term prognosis and outcome study of elderly hypertensives (aged 60 years or over) was made based on the 20-year prospective population survey conducted in a Japanese rural community (Hisayama) and the results were compared with those for younger subjects (aged 40-59 years). The risk of cardiovascular mortality related to blood pressure level increased with the elevation of either systolic or diastolic pressure in both younger and elderly groups. Cardiovascular mortality increased markedly at a systolic pressure of greater than or equal to 160 mmHg, or a diastolic pressure of greater than or equal to 100 mmHg for those aged 40-59 years. There was no cut-off level for increased risk of cardiovascular mortality for either systolic or diastolic pressures for those aged 60 years or over. Stroke mortality was seven times higher in systolic, and 10 times higher in diastolic hypertensives than in normotensives (P less than 0.01) for the group aged 40-59 years. However, deaths due to stroke and heart disease were more frequently associated with borderline (relative risk 2.3 and 2.3, respectively; P less than 0.01), systolic (relative risk 3.2 and 3.7, respectively; P less than 0.01) and diastolic hypertension (relative risk 2.1 and 4.8, respectively; P less than 0.01), compared to normotension for those aged 60 years or over. Intracerebral hemorrhage and cerebral infarction occurred more frequently in diastolic hypertensives for both young (relative risk 9.8 and 4.8, respectively; P less than 0.01) and elderly subjects (relative risk 3.4 and 1.5, respectively; P less than 0.01) than in normotensives.(ABSTRACT TRUNCATED AT 250 WORDS)