For hypertensive patients, it has been recommended that antihypertensive treatment strategies be chosen on the basis of the patients' conditions and age. In this sub-analysis of the Candesartan Antihypertensive Survival Evaluation in Japan (CASE-J) trial, we aimed to compare the effects of candesartan and amlodipine on cardiovascular mortality and morbidity in Japanese elderly patients with high-risk hypertension and to determine their optimal target blood pressures (BPs). The effect of the two drugs on cardiovascular events was compared across different age subgroups (<65, 65-74, and 75-84 years) by use of Cox regression analysis. We also evaluated the associations between the achieved BP and the incidence of cardiovascular events, irrespective of the allocated drugs in multiple Cox regression analyses. The incidence of cardiovascular events was independent of the assigned treatment for each of the age subgroups. For systolic BP (SBP), cardiovascular risk increased steeply when control of SBP was inadequate (higher than 140 mmHg) for patients younger than 65 years old and those between 65 and 74 years old. Patients aged 75 to 84 years old showed a significantly increased risk when their SBP was >or=150 mmHg. For diastolic BP (DBP), the risk significantly increased for the subgroup aged 75 to 84 years when the DBP was >or=85 mmHg. The present results show that candesartan and amlodipine are equally effective in Japanese elderly patients with high-risk hypertension. Moreover, it is important to control BP levels to less than 150/85 mmHg for patients 75-84 years old.
Trial registration: ClinicalTrials.gov NCT00125463.