(243) Comorbidities and Numbers of Drugs Prescribed Influence the Potential Drug Interactions in Pulmonary Tuberculosis Patients in A Public Hospital in Banjarmasin, Indonesia

Background: Pulmonary tuberculosis (TB) patients receive a combination of anti-tuberculosis drugs and other drugs during their therapy period, that may trigger potential drug interactions.

Objectives: This study aimed to determine the factors that influence potential drug interactions in pulmonary TB patients in a public hospital in Banjarmasin, South Kalimantan, Indonesia.

Methods: The design of this study was cross-sectional. Subjects included were pulmonary TB adult patients who visited or admitted to a public hospital in Banjarmasin during 2021-2022. Independent variables included age, gender, comorbidities, and number of drugs prescribed. The dependent variable was potential drug interactions, assessed using the Lexicomp Drug Interactions tool, and classified based on severity and risk rating. Data were obtained from patients’ medical records. The associations between independent and dependent variables were analyzed using multivariate logistic regression.

Results: A total of 128 patients and 673 prescriptions were included. Most patients were aged 18-64 years (87.5%), males (68.0%), without comorbidities (74.2%), and received polypharmacy (52.2%). Potential drug interactions occurred in 61.3% of prescriptions, most of which were moderate in severity (85.9%) with a risk rating of C (64.9%). Rifampicin was the most common drug that potentially interacted with other drugs. The occurrence of major potential drug interactions was 0.3% and the occurrence of potential interaction with the risk rating of X was 20.3%. Comorbidities (aPOR 1.67, 95%CI 1.20-2.34) and number of drugs prescribed (aPOR 11.80 [95%CI 8.12-17.15] for polypharmacy, aPOR 305.07 for hyperpolypharmacy) were significantly associated with potential drug interactions. In addition, hyperpolypharmacy was significantly associated with the severity of the interaction; and comorbidities were significantly associated with the interaction risk rating, but both of these associations were assumed to be influenced by other confounding factors that were not studied.

Conclusions: It can be concluded that comorbidities and the number of drugs prescribed significantly influence potential drug interactions in pulmonary TB patients in a public hospital in Banjarmasin. Health providers need to be more aware of these significant factors and their effects on drug interactions when prescribing non-anti-TB drugs to TB patients.