Does atenolol improve physical and psychological function after coronary artery bypass surgery: a controlled study

A double-blind prospective randomized trial of atenolol (100 mg once daily) was carried out on 88 patients (78 men) awaiting coronary artery bypass graft surgery. Standardized ratings of both psychiatric morbidity and functional capacity were made before, 3 months (n = 82) and 12 months (n = 81) after surgery. One year after surgery men in the atenolol group had a significantly shorter treadmill exercise time than those on placebo (7.21 +/- 0.28 min vs 8.32 +/- 0.40 min; p less than 0.05), but the frequency of reported anginal attacks during the year was similar in both drug groups. Improvement in functional capacity (measured in exercise time) in the 71 men following surgery was related to both physical and psychological variables assessed before the operation. Men with more severe occlusive disease, lower neuroticism and higher extraversion scores pre-operatively showed greater percentage improvement in exercise time after surgery. Women had significantly levels of psychiatric morbidity and shorter treadmill exercise time than men both before and after surgery. Of the psychiatric and psychological variables, only ratings of Type A behaviour fell significantly in the atenolol group (170.9 +/- 5.3 vs 163.0 +/- 5.2; p less than 0.05). This change, which is probably not clinically important, occurred independently of any reduction in either overall psychiatric morbidity score or ratings of somatic symptoms mediated by beta-adrenergic receptors. The atenolol group reported more side-effects of both psychological and physical symptoms than the placebo group. We do not recommend the routine use of atenolol after bypass graft surgery. Our findings failed to support the suggestion that Type A characteristics may reflect an underlying sympathetic nervous system reactivity.