Effects of 100 mg of Controlled‐Release Metoprolol and 100 mg of Atenolol on Blood Pressure, Central Nervous System‐Related Symptoms, and General Well Being

Central nervous system (CNS)-related symptoms and quality of life during treatment with controlled-release (CR) metoprolol and a standard formulation of atenolol were compared in a double-blind crossover study in 60 patients with mild to moderate hypertension. After a 4-week placebo run-in period, each beta 1-adrenoceptor blocker was administered at a dosage of 100 mg once daily for 6 weeks. Quality of life was assessed regularly during the active treatment phases by use of two standardized self-administered questionnaires, the minor symptom evaluation (MSE) profile, and the psychologic general well-being (PGWB) index. Both questionnaires have previously been shown to be effective in detecting CNS symptoms and changes in well being produced by beta-blockers. Blood pressure and heart rate were monitored to assess the antihypertensive efficacy of the two drugs. Metoprolol CR and atenolol produced equivalent, clinically effective reductions in systolic and diastolic blood pressures measured 24 hours after administration. The drugs were found to exert similar effects on general well being, as assessed by the PGWB index, and there were no significant differences between the two treatments with regard to the three dimensions of the MSE profile, contentment, vitality, and sleep. Thus, at equivalent antihypertensive dosages, metoprolol CR and atenolol are clinically comparable with regard to the degree of CNS-related symptoms produced and effects on general well being. Because these agents differ markedly in lipophilicity, other factors, such as beta 1-selectivity/nonselectivity, may be more important determinants of whether these subjective symptoms occur during therapy with beta-blockers.