Early Corrected QT Interval Changes Following First-dose Long-acting Injectable Antipsychotics: A Retrospective
Hayriye Dilek Hamurcu1, Esra Kabadayi Sahin2, Ersin Hatice Karslıoğlu3
1Department of Psychiatry, Dr. Abdurrahman Yurtaslan Oncology Research And Training Hospital, University of Health Sciences, Ankara, Türkiye.
Summary
Long-acting injectable antipsychotics showed minimal early cardiac effects. Baseline QTc, not LAI type, predicted post-injection QTc, suggesting routine ECG monitoring is sufficient for low-risk patients.
Area of Science:
- Cardiology
- Psychiatry
- Pharmacology
Background:
- Long-acting injectable (LAI) antipsychotics enhance treatment adherence and reduce relapse rates in psychiatric patients.
- However, potential short-term cardiac effects during the critical initial dosing period are not well understood.
Purpose of the Study:
- To investigate early changes in corrected QT (QTc) intervals within 7-14 days following the first LAI antipsychotic dose.
- To determine if QTc variations differ based on the type of LAI administered and common clinical factors.
Main Methods:
- A retrospective chart review was conducted on psychiatric inpatients receiving their initial LAI antipsychotic during hospitalization.
- Electrocardiograms (ECGs) were analyzed pre-LAI and 7-14 days post-injection, with QTc calculated using Bazett's formula.
- Subgroup analyses explored differences across various clinical characteristics.
Main Results:
- Sixty-three patients with paired ECGs showed small, non-significant overall QTc changes (mean change < 10 ms).
- Second-generation LAIs, particularly paliperidone palmitate, and concomitant anticholinergic use were associated with modest QTc increases.
- Baseline QTc was the sole independent predictor of post-injection QTc.
Conclusions:
- Early QTc alterations following LAI initiation are minimal and not clinically significant.
- Baseline QTc is the primary determinant of post-injection QTc, supporting standard ECG monitoring protocols for low-risk individuals.
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