Racial susceptibility for QT prolongation in acute drug overdoses

J Electrocardiol. 2014 Mar-Apr;47(2):244-50. doi: 10.1016/j.jelectrocard.2013.12.002. Epub 2013 Dec 4.

Abstract

Background and purpose: QT prolongation independently predicts adverse cardiovascular events in suspected poisoning. We aimed to evaluate the association between race and drug-induced QT prolongation for patients with acute overdose.

Methods: This was a cross-sectional observational study at two urban teaching hospitals. Consecutive adult ED patients with acute drug overdose were prospectively enrolled over a two year period. The primary outcome, long-QT, was defined using standard criteria: QTc>470 ms in females and>460 ms in males. The association between race and drug-induced QT prolongation was tested, considering several confounding variables.

Results: In 472 patients analyzed (46% female, mean age 42.3), QT prolongation occurred in 12.7%. Blacks had two-fold increased odds of drug-induced QT prolongation (OR 2.01, CI 1.03-3.91) and Hispanics had 48% decreased odds of drug-induced QT prolongation (OR 0.52, CI 0.29-0.94).

Conclusions: We found significant racial susceptibility to drug-induced QT prolongation in this large urban study of acute overdoses.

Keywords: Overdose; QT prolongation; Racial differences.

Publication types

  • Multicenter Study
  • Observational Study
  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • Cross-Sectional Studies
  • Drug Overdose*
  • Electrocardiography*
  • Emergency Service, Hospital
  • Female
  • Hospitals, Teaching
  • Hospitals, Urban
  • Humans
  • Long QT Syndrome / chemically induced*
  • Long QT Syndrome / ethnology*
  • Male
  • Middle Aged
  • Prospective Studies
  • Racial Groups*
  • Risk Factors