Heart risk associated with weight loss in anorexia nervosa and eating disorders: electrocardiographic changes during the early phase of refeeding.

Refeeding syndromes with electrolyte aberrations, heart failure and arrhythmias may complicate the nutritional rehabilitation of emaciated patients with eating disorders. Therefore, electrocardiographic (ECG) changes and changes in serum electrolyte concentrations following refeeding were studied in 37 admissions of 32 teenage girls with eating disorders. On admission they were all on a weight-losing course and weighed 37.0+/-8.0 kg (mean +/- SD) following a weight loss of 14.2+/-7.2 kg. On ECG recordings there was a prolongation of the QT interval and an increased QT dispersion. Serum concentrations of sodium, potassium and magnesium were with few exceptions normal. Serum concentrations of creatinine were high in relation to the low body weight, indicating protein catabolism. The first 2 wk of refeeding resulted in a weight gain of 1.7+/-0.2 kg without signs of refeeding syndromes or electrolyte aberrations. QT prolongation and dispersion normalized within the 3 d of refeeding. It is concluded that oral refeeding of patients with eating disorders and weight loss can be performed efficiently and without causing refeeding syndromes. QT pathology, a consequence of acute starvation and a risk factor for cardiac arrhythmias, normalizes within days. In view of the need to balance adequate refeeding and reduction of QT pathology against the risks of refeeding syndromes the start of refeeding of severely emaciated patients is best performed in a hospital setting where monitoring of ECG and serum electrolytes is possible.