Prevalence of ventricular repolarization abnormalities in subjects on psychotropic drugs in Nigeria: A cross-sectional comparative study

Abstract

Introduction: Patients on psychotropic medications are at high risk of cardiac adverse effects and sudden death. However, the adverse effect burden of these drugs is grossly underreported in most African countries including Nigeria. The study aimed to evaluate the prevalence of ventricular repolarization electrocardiographic abnormalities (QTc, QTd, TpTe, and TpTe/QT) among patients taking psychotropics.

Methods: This study was conducted among 150 psychiatric patients on psychotropics and 75 controls. All subjects had resting electrocardiogram. QTc was determined using Bazett formula, QT dispersion was determined by subtracting shortest from longest QT in a 12-lead ECG, and Tpeak to Tend was measured from Tpeak to Tend in V5.

Results: The prevalence of prolonged QTc and QT dispersion in patients were significantly higher than the controls (24.7% vs. 4%; p<0.001 and 17.3% vs. 1.3%; p<0.001 respectively). The mean QTc and QT dispersion were significantly higher than the control group (418.5±28.1 ms vs 390.4±21.9ms; p<0.001 and 53.17±23.1ms vs. 43.7113.4ms; p=0.001 respectively). There was no statistically significant difference in the mean TpTe and TpTe/QT in both study groups.

Conclusion: Psychotropic drugs influence QTc and QT dispersion prolongation. This study showed that chronic use of psychotropics is associated with increased risk of ventricular repolarization abnormalities among this population.