QTc Interval in psychiatric inpatients: A retrospective study

Abstract

Introduction

Several psychotropic medications (i.e. antipsychotics, antidepressant) have been recently associated with QTc prolongation. Despite literature data report only mild prolongation of QTc following the use of antidepressants or typical antipsychotics, post-marketing studies have clearly evidenced an increased risk of QTc prolongation and potentially lethal arrhythmias (i.e. torsade de pointes) in psychiatric patients.

Objectives

We aimed to evaluate the prevalence of prolonged QTc and to identify potential predictors influencing QTc in a psychiatric inpatient population.

Methods

Medical records of 200 patients admitted to our psychiatric ward between 2007 and 2012 were retrospectively reviewed.

Results

Prevalence of prolonged QTc at admission was very low (0.1%). No significant differences in QTc interval were observed between patients taking or not antipsychotics (P = 0.66), mood stabilizers (P = 0.36), or antidepressants (P = 0.07). A statistically significant difference was observed between patients on depot formulation and patients who were taking oral antipsychotic (P = 0.02). However, the pharmaceutical class of the medications appeared not significant.

Conclusions

We observed a very low rate of QTc prolongation in psychiatric inpatients at admission. Surprisingly we did not find a significant effect of specific medications; however, in our sample intramuscular formulation was associated with lower QTc interval.

Disclosure of interest

The authors have not supplied their declaration of competing interest.