EP.68Carnitine deficiency in patients with Duchenne muscular dystrophy requiring long-term tube feeding and heart function improvement by carnitine replacement

Abstract

Carnitine deficiency and the effects of long-term carnitine supplementation were investigated in 4 patients with Duchenne muscular dystrophy (DMD) requiring long-term feeding tube. All the patients were tube-fed for 40 months or longer and were on enteral nutrition without supplemented carnitine. They had carnitine deficiency or free carnitine levels that were below normal levels. They were administered 1,500 mg of carnitine replacement daily for 6 years. Their free carnitine levels normalized 1 month after initiating carnitine replacement therapy. However, although patients showed improvement with long-term carnitine replacement therapy, their ejection fraction (EF) was significantly low at baseline and continued to decrease until 2 years of carnitine replacement but tended to increase at 3 years and onward after initiating carnitine replacement therapy. It is unlikely that EF improves in the clinical course of DMD; therefore, it was considered an effect of long-term carnitine replacement therapy. The most common cause of death in patients with DMD is heart failure. Thus, the results of this study suggested that carnitine supplementation improves vital prognosis in patients with DMD.