Prognosis after withdrawal of chronic postinfarction metoprolol treatment: a 2–7 year follow-up

Abstract

In a randomized double-blind postinfarction study 301 patients were treated with either metoprolol 100 mg b.i.d. (n= 154) or placebo (n= 147) for three years. After the three-year treatment period the study preparation was gradually withdrawn over one week, followed by another 2–7 year follow-up. Mortality and morbidity data were studied both during the intervention period (reported elsewhere) and over the period following withdrawal of study therapy. During the period following the withdrawal of the trial preparation, there were 16 (14%) and 31 (24%) deaths in the previously placebo and metoprolol groups, respectively (P = 0.10). Corresponding figures for reinfarctions and cerebrovascular events were 15 (13%) vs. 12 (9%) and 14 (12%) vs. 9 (7%) (NS). From a Cox regression analysis taking 13 different variables into account, a model describing the risk for subsequent death was constructed. The model identified the following important variables: sex (relative risk (rr) = 2.4), beta-blocker withdrawal (rr = 2.l), performance on exercise test and digitalis treatment (rr = 2.3, P < 0.05). The present results, as well as those from other studies, seem to favour continuous postinfarction beta blocker therapy provided that there are no severe side-effects from therapy. Digitalis therapy in postinfarction patients in sinus rhythm may have adverse effects on survival during long-term follow-up.