QTc interval prolongation in pediatric eating disorder population

Eating disorders in pediatric populations are associated with several cardiac complications, including QTc prolongation, which can lead to fatal arrhythmias. While some studies suggest eating disorders inherently lead to QTc prolongation, emerging evidence suggests extrinsic factors may play a greater role.

This retrospective chart review evaluates QTc interval prolongation in pediatric patients with eating disorders at a tertiary children's hospital. Demographic factors, ECGs, electrolyte levels, and the use of QTc-prolonging medications were analyzed to evaluate their association with QTc prolongation.

Among 435 patients, 405 had normal QTc intervals (<440 ms), 8 were borderline prolonged (440-460 ms), and 22 had prolonged intervals (>460 ms) using the Bazett calculation. Mean QTc values differed significantly across eating disorder subtypes (p = 0.0063), with the longest values observed in bulimia nervosa and binge eating disorder, and the shortest in anorexia nervosa. Patients taking one or more QTc-prolonging medications had a longer mean QTc interval than those not taking medications (p < 0.001). There were significant inverse correlations between serum calcium (p = 0.0001), magnesium (p = 0.01), and potassium (p = 0.003) levels and QTc length.

These findings suggest QTc-prolonging medications and electrolyte abnormalities can be associated with longer QTc intervals in pediatric patients with eating disorders and should continue to be monitored as modifiable risk factors.