Risk Assessment of QT-Prolonging Drug Combinations and Their Association with QTc Interval Prolongation Among Psychiatric Patients: A Prospective Observational Study

Abstract

Drug-induced QT interval prolongation is a clinically significant adverse effect of several psychotropic medications and may lead to life-threatening ventricular arrhythmias, including Torsades de Pointes. Psychiatric patients are particularly susceptible because of polypharmacy, comorbidities, and frequent exposure to QT-prolonging drugs. Objective: To assess the prevalence of QT-prolonging drug combinations and their association with QTc interval prolongation among psychiatric patients receiving psychotropic medications. Methods: A prospective observational study will be conducted among adult psychiatric patients receiving at least one QT-prolonging medication. Demographic, clinical, medication, laboratory, and ECG data will be collected. QT-risk medications will be classified using CredibleMeds®, drug interactions will be assessed using a validated interaction database, and patient risk will be evaluated using the Tisdale Risk Score. Statistical significance will be considered at p < 0.05. Expected Results: QT-prolonging drug combinations are anticipated to be common and associated with prolonged QTc intervals. Polypharmacy, advanced age, electrolyte abnormalities, and higher Tisdale Risk Scores are expected to be major predictors. Pharmacist-led interventions are anticipated to improve medication safety through optimization of therapy and enhanced ECG monitoring. Conclusion: The study is expected to provide evidence regarding the burden and determinants of QT-prolonging drug combinations in psychiatric practice. The findings may support routine QT-risk assessment, evidence-based prescribing, regular ECG monitoring, and pharmacist-led medication review to improve patient safety and reduce preventable cardiac adverse events