QT-prolonging antipsychotic combinations and associated risk in hospitalized patients with mental disorders in Sana'a, Yemen.

Prolongation of the QT interval is associated with serious and potentially life-threateningcardiac complications, requiring careful clinical attention. Psychiatric inpatients frequently receive multiple antipsychotic medications, some of which are known to affect cardiac repolarization. This study aimed to describe the patterns of QT-prolonging antipsychotic drug combinations and their associated drug-drug interaction (DDI) risk among hospitalized male participants in Sana'a, Yemen. A retrospective cross-sectional study was conducted using medical records of inpatients admitted to two psychiatric hospitals between November 2023 and June 2024. A total of 191 male participants aged 17-65 years who received antipsychotic polypharmacy for at least one week were included. Electrocardiogram (ECG) monitoring at admission was available for 47 participants. Prescribed medications were screened for QT-prolonging potential and interaction severity using the Arizona Center for Education and Research on Therapeutics (AZCERT) database. Overall, 395 QT-prolonging antipsychotic prescriptions were identified. Among participants receiving antipsychotic combinations, 36% were prescribed at least one strong-to-moderate QT-prolonging combination. Of the 47 participants who underwent ECG monitoring, 39.3% received drugs classified by AZCERT as having a known risk of torsades de pointes (TdP). Borderline QTc intervals were observed in 10.6% of participants, while 6.4% exhibited prolonged QTc intervals. These findings highlight the presence of QTc abnormalities within a pre-selected subgroup of psychiatric inpatients already receiving QT-prolonging antipsychotic polypharmacy. While no cases of TdP were observed, the results underscore the importance of enhanced clinical vigilance, routine ECG monitoring, and careful selection of antipsychotic combinations. Future studies including comparator groups are needed to quantify the incremental risk of QTc prolongation and TdP.