Vitamin E increases the risk of developing heart failure after myocardial infarction: results from the GISSI-Prevenzione trial

OBJECTIVE: Although results from basic science suggested a protective role of vitamin E treatment in the prevention of cardiovascular disease, recent evidence indicates increased cardiovascular mortality due to vitamin E treatment. Recently, the HOPE trial showed an increment of the incidence of congestive heart failure (CHF) in patients treated with vitamin E. METHODS: We explored the effect of vitamin E on development of CHF in 8415 postinfarction patients without CHF at baseline, with an echocardiographic measure of left ventricular ejection fraction, who have been followed up for 3.5 years in the GISSI-Prevenzione trial. CHF during follow-up was defined as hospitalization or death for CHF. Cox regression models adjusted for relevant prognostic indicators were fitted. RESULTS: Main clinical characteristics were balanced in the 4202 and 4213 patients allocated vitamin E and control group, respectively. During follow-up, 220 patients (2.6%) developed CHF. Patients allocated vitamin E had a nonsignificant 20% (95% confidence intervals 0.92-1.56, P = 0.18) increased risk of developing CHF. Vitamin E treatment, however, was associated with a significant 50% increase (95% confidence intervals 1.03-2.20, P = 0.034) of CHF in patients with left ventricular dysfunction (ejection fraction < 50%). CONCLUSIONS: Our results confirm and extend previous evidence on the possible harmful effect of vitamin E on ventricular function in patients with cardiovascular disease. Available evidence should discourage the use of vitamin E in patients with left ventricular dysfunction.