Effect of coenzyme Q(10) in Europeans with chronic heart failure: A sub-group analysis of the Q-SYMBIO randomized double-blind trial

BACKGROUND: Geographical differences in patient characteristics, management and outcomes in heart failure (HF) trials are well recognized. The aim of this study was to assess the consistency of the treatment effect of coenzyme Q(10) (CoQ(10)) in the European sub-population of Q-SYMBIO, a randomized double-blind multinational trial of treatment with CoQ(10), in addition to standard therapy in chronic HF. METHODS: Patients with moderate to severe HF were randomized to CoQ(10) 300 mg daily or placebo in addition to standard therapy. At 3 months the primary short-term endpoints were changes in New York Heart Association (NYHA) functional classification, 6-min walk test, and levels of N-terminal pro–B type natriuretic peptide. At 2 years the primary long-term endpoint was major adverse cardiovascular events (MACE). RESULTS: There were no significant changes in short-term endpoints. The primary long-term endpoint of MACE was reached by significantly fewer patients in the CoQ(10) group (n = 10, 9%) compared to the placebo group (n = 33, 27%, p = 0.001). The following secondary endpoints were significantly improved in the CoQ(10) group compared with the placebo group: all-cause and cardiovascular mortality, NYHA classification and left ventricular ejection fraction (LVEF). In the European sub-population, when compared to the whole group, there was greater adherence to guideline directed therapy and similar results for short- and long-term endpoints. A new finding revealed a significant improvement in LVEF. CONCLUSIONS: The therapeutic efficacy of CoQ(10) demonstrated in the Q-SYMBIO study was confirmed in the European sub-population in terms of safely reducing MACE, all-cause mortality, cardiovascular mortality, hospitalization and improvement of symptoms.