T-wave morphology descriptors in patients with bulimia nervosa

Purpose: Bulimia nervosa (BN) is associated with increased risk of cardiovascular disease and arrhythmias. Some reports found abnormal electrocardiographic markers of arrhythmias in BN, while others did not. This study investigated novel parameters of T-wave morphology that were reported to be associated with adverse cardiovascular outcomes in other patient groups, among patients with BN under medical care. Method: Thirty-five BN patients and 76 healthy controls were included. Total cosine R to T (TCRT) and T-wave Morphology Dispersion (TMD) parameters were computed according to accepted standards for an average beat and a random beat. Patients were followed for 11.1 ± 0.1 years for the emergence of arrhythmias or events of sudden death. Results: Twenty-five (71.4%) BN patients were hospitalized when enrolled, for a mean duration of 1.1 ± 0.2 months. The rest were ambulatory patients. The BN group had lower blood pressure, more smokers, and used antidepressants, neuroleptic drugs and benzodiazepines more than controls did. Other demographic parameters were comparable between groups. TCRT and TMD parameters were statistically similar and within the normal ranges reported by other research groups. None of the BN patients had prolonged QTc interval or electrolyte abnormalities on inclusion. During the follow-up period, no clinical symptoms suggestive of arrhythmias were reported, and no cardiovascular-related hospitalizations or deaths occurred in either group. Conclusion: Medically treated BN patients have normal T-wave morphology parameters and hence, low risk for repolarization-associated malignant ventricular arrhythmias. The prognostic importance of these novel repolarization parameters remains to be explored among untreated patients, those who ingest emetic substances and patients with electrolyte imbalance. Level of evidence: Level III.