F. J. Zacharias

A trial of oral propranolol as a hypotensive agent was designed to provide adequate treatment periods. Twenty-eight patients with essential hypertension, with a mean blood pressure of 190/111 mm. Hg, were controlled on 120-320 mg. of propranolol daily. Their mean treated blood pressure was 153/91. They then entered, on a randomized and double-blind basis, a cross-over trial of two 16-week periods, blood pressure being measured fortnightly. Propranolol caused a statistically significant fall in blood pressure when compared with placebo. When propranolol was withdrawn blood pressures rapidly rose to hypertensive levels, though not to untreated levels. No postural hypotension was found, but a small change in blood pressure levels on exercise was noted.

The aim of the present study was to monitor the efficacy of treatment, morbidity and mortality over a 10-year period in 939 moderate to severe hypertensive patients. All patients were treated in the same hypertension clinic with the beta 1-selective agent atenolol, administered either alone or more usually with a diuretic with or without a vasodilator or other agents. Survival rates were compared with predicted survival rates, had the hypertension not been treated, and also with those of a local reference population matched for age and sex. After a mean follow-up time of 6.1 years, mean blood pressure (BP) was significantly lowered from 183/109 to 145/87 mmHg. Biochemical disturbance was minimal. There were 79 withdrawals from treatment, of whom 37 were lost to follow-up. There were 91 deaths on intention to treat. Systolic blood pressure (SBP) on treatment, and not initial BP, was a powerful predictor of mortality. Patients of all age groups with well-controlled SBP were less likely to die, particularly from myocardial infarction, than those with less well controlled SBP (P less than 0.001). However, due to possible J-curve relationships between treated BP and outcome, lowering SBP below 140-150 mmHg in the elderly, and the diastolic blood pressure (DBP) below about 85 mmHg, may not be beneficial. Total mortality and mortality due to myocardial infarction was about 60% [corrected], of predicted level, had a high BP not been treated, being similar to that in a local reference control population (age- and sex-matched). The death rate from stroke was reduced to about 50% of that predicted. Patients who died showed a mean fall in mean serum triglyceride concentration in contrast to the mean increase that occurred in survivors. It is concluded that patients with moderate to severe hypertension who obtain a high level of general health care and optimal control of BP for up to 10 years, experience a significant decrease in total mortality rate and death from myocardial infarction and stroke.