Practical Approaches to Antipsychotic-Associated Corrected QT Interval Prolongation in Patients With Serious Mental Illness: A Review of Cases

Background: There is no consensus for assessment and management of patients with serious mental illness (SMI) who are at risk for cardiac morbidity and mortality due to antipsychotic-associated QTc prolongation. Objective: The objective of this review was to assess methods for risk scoring, QT correction calculation, and clinical management in SMI patients with antipsychotic-associated QTc prolongation. Methods: A search was performed in PubMed for case reports that described QTc prolongation in adult patients with schizophrenia or bipolar disorder prescribed an antipsychotic. Reports published in North America between 2000 and 2020 were eligible. The Mayo, Tisdale, and RISQ-PATH scoring tools were applied to cases to categorize risk level. Results: Seventeen cases were included. Most patients were prescribed a second-generation antipsychotic for schizophrenia, with baseline and maximum QTc values of 429 milliseconds and 545 milliseconds, respectively. The Mayo scoring tool identified 17 (100%) cases as "high risk," Tisdale identified 9 (53%) cases as "moderate risk" and 7 (41%) cases as "low risk," while RISQ-PATH identified 9 (53%) cases as "not low risk" and 8 (47%) cases as "low risk." Three cases reported the QT correction formula utilized (18%). The most common intervention to address antipsychotic-associated QTc prolongation was switching to a different antipsychotic (35%). Approximately one third of patients experienced Torsades de Pointes. Conclusion: There is a lack of standardization for antipsychotic-associated QTc prolongation risk assessment and management in patients with SMI. This review provides real-world data representing actual clinical practice.