Guidelines for Hypertension in the 1999 Revised Version-Elderly

Hypertension is a major risk factor contributing to the second and third most frequent causes of death in Japan: cerebrovascular diseases and heart diseases. Hypertension incidence increases with age, occurring in approximately 60% of Japanese aged 65 yr and older (1), and being the most prevalent disease in Japan (2). In our country, where the elderly population has been increasing, hypertension is one of the most important diseases to be controlled and treated, and counter measures against the disease have drawn much public attention. Hypertension in the elderly consists mostly of essential hypertension, and its pathophysiology differs in many ways from that of essential hypertension in the young or middle-aged. However, isolated systolic hypertension (systolic pressure 140 mmHg or greater, diastolic pressure below 90 mmHg) has been increasing in the elderly. Isolated systolic hypertension is divided into two groups, namely so-called "burned out" and "de nova" type systolic hypertension. The former type of hypertension generally starts in middle age as essential hypertension until, eventually, the diastolic pressure becomes reduced in old age; while the latter type of hypertension appears in old age due to reduced vascular compliance in large arteries. In addition, there are also cases of secondary hypertension due to specific causes such as renovascular hypertension. In the elderly, it has been reported that systolic blood pressure, more than diastolic blood pressure is strongly associated with cardiovascular diseases, especially stroke, coronary artery disease, cardiac failure, end-stage renal disease, and all-cause mortality (3). Furthermore, it has become apparent that raised pulse pressure (systolic blood pressure-diastolic blood pressure) may increase the risk of such diseases (4). The pathophysiology of hypertension in the elderly is characterized by increased total peripheral vascular resistance, decreased compliance of large and medium-sized arteries, a tendency toward decrease in cardiac output, decreased circulating blood volume, increased instability of blood pressure due to decreased baroreceptor function, decreased blood flow and dysfunction of autoregulation in the brain, heart and kidney. Therefore, given the above-mentioned pathophysiological characteristics, hypertension in the elderly should be treated. In addition, as with other diseases in the elderly, it is necessary to pay attention to the ADL, QOL and drug compliance of patients. Based on large-scale intervention trials in Western countries and China, treatment of hypertension including systolic hypertension in the elderly has been widely confirmed to be effective (5-10). However, the efficacy of such treatment of hypertensive patients aged 85 yr or older is less certain. It has been proved that occurrence of cerebrovascular disease, coronary artery disease and cardiac failure, in addition to all-cause mortality are decreased by diuretics or long-acting dihydropyridine Ca antagonists. Although treatment of hypertension in the elderly with /9-blockers significantly decreases morbidity and mortality of cerebrovascular disease, it has not been shown to demonstrate a significant decrease in morbidity and mortality of coronary artery disease (11). In the United States in 1994, the therapeutic guidelines of hypertension in the elderly were published by the National High Blood Pressure Education Program Working Group