Quality of life among hypertensive patients with a diuretic background who are taking atenolol and enalapril. The cardioselective beta-blocker atenolol and the angiotensin-converting enzyme inhibitor enalapril were compared for efficacy, safety, and quality-of-life factors in 30 patients with hypertension whose hypertension was inadequately controlled with diuretic alone. Atenolol (50 to 100 mg once a day) and enalapril (2.5 to 40 mg once a day), combined with hydrochlorothiazide (25 mg once a day), had similar levels of efficacy and safety. A comprehensive battery of psychologic assessments for quality of life was administered, including measures of anxiety, depression, psychiatric symptoms, memory, and psychomotor function. These five conceptually based clusters were first analyzed by multivariate analysis of variance procedures, followed by univariate analyses of the individual variables composing each domain. In general, neither atenolol nor enalapril was associated with major changes in psychologic functioning. The only data cluster with a statistically significant change was memory function, primarily as a result of lower scores of the digit span (backward) test, for atenolol relative to enalapril. These preliminary findings suggest that atenolol and enalapril have comparable degrees of efficacy and safety, with no major disparities in quality-of-life effects, for hypertensive patients with a history of taking diuretics and this sort of quality-of-life assessment can be performed during trials of antihypertensive drugs. 