Monitoring of QTc in subjects hospitalized for 1 year in an acute psychiatric ward treated with clotiapine and other associated antipsychotics: a retrospective study

Background: Many antipsychotic medications are responsible for prolonging QTc, a risk factor for sudden death, which is one of the main causes of reduced life expectancy in patients with mental health disorders. Objectives: To evaluate the cardiac safety profile of clotiapine in a naturalistic setting. Design: This observational, retrospective study included 70 subjects hospitalized at the Service of Psychiatry Diagnosis and Care in Modena from February 1, 2023 to July 31, 2024, treated with clotiapine. Methods: Demographic and clinical data were collected, along with electrocardiographic measurements (QTc) taken at the start of treatment (T0), after at least 7 days of therapy (T1), and at further follow-up (T2) after 7–21 days. Prolongation was considered when QTc exceeded 500 ms or an increase of 60 ms compared to baseline, according to international standards. Results: QTc prolongation was limited (m = 4.59 ms), representing an increase of 1.07%, without reaching thresholds of significant clinical risk. Subjects with an increase equal to or greater than the median (M = 3.5) of QTc increase at T1 accounted for half of the sample, and only one patient had an increase greater than 60 ms. Conclusion: Clotiapine treatment, also in combination with haloperidol, had minimal prolongation of QTc within the limits of clinical safety. A stabilization of QTc over time was observed, indicating a possible adaptation to treatment. Methodological limitations of this study call for further research.