Incidence and Risk Factors Associated with QT Prolongation in Drug-Resistant Tuberculosis Patients Receiving Bedaquiline at Makarak Hospital, Kanchanaburi Province

Abstract

Objective: The purpose was to study the incidence and risk factors associated with QT prolongation and the severity of QT prolongation in drug-resistant tuberculosis patients treated with bedaquiline at Makarak Hospital, Kanchanaburi Province.

Methods: A retrospective descriptive study was conducted by collecting data from drug-resistant tuberculosis (DR-TB) patients aged 15 years and older who received treatment regimens containing bedaquiline at Makarak Hospital, Kanchanaburi Province, from January 1, 2018, to May 31, 2024. Data were presented as numbers, percentages, means, and standard deviations. Factors associated with the occurrence of QT prolongation on electrocardiograms (ECGs) were analyzed using independent t tests and chi-square tests.

Results: It was found that among 76 patients, the incidence of QT prolongation on electrocardiograms (ECGs) was 40.8%. Age, serum potassium levels, baseline QTcF interval before treatment initiation, baseline heart rate (beats per minute), and impaired liver function (ALT greater than three times the upper limit of normal) were significantly associated with QT prolongation (p < .05). Conversely, gender, body mass index (BMI), comorbidities, drug-resistant tuberculosis treatment regimens, the number of drugs affecting QT prolongation in the regimens, the types of drugs affecting QT prolongation in the regimens, concomitant medications influencing QT prolongation, and impaired liver function (AST greater than three times the upper limit of normal) were not significantly associated with QT prolongation. Regarding the severity of QT prolongation, the majority of cases were classified as Grade 1 (61.3%). Treatment completion was achieved in 67.7% of patients.

Conclusion:  Treatment of drug-resistant tuberculosis (DR-TB) with regimens containing bedaquiline showed a relatively high incidence of QT prolongation on electrocardiograms (ECGs). Most cases were of mild severity, allowing patients to complete the treatment without interruption. However, close monitoring is essential, particularly for elderly patients with pre-existing ECG abnormalities before treatment initiation. Emphasis should also be placed on regular monitoring of serum potassium levels and liver function during bedaquiline treatment to prevent fatal outcomes associated with this condition.