Assessment of Potential Drug-Drug Interactions in Obese Patients

Abstract

Aim: Polypharmacy may cause life-threatening adverse effects due to drug-drug interactions (DDIs). It is possible to observe DDIs due to polypharmacy in obese patients who is known to have many co-morbid diseases that necessitates multiple drug use. The aim of the present study is to determine the frequency and severity of potential DDIs (pDDIs) in obese patients. Material and Methods: This cross-sectional study analyzed the patient charts that admitted to obesity outpatient clinic of tertiary care hospital from April 1, 2016 to July 1, 2017. The severity of DDIs was interpreted using the Lexi-comp® drug interaction database. A chi- square test was performed for the comparison of the presence of DDIs based on patients’ demographic characteristics [gender (male/ female), age categories (18-44, 45-64 and ?65 years) and BMI (30-34.9, 35-39.9 and ?40 kg/m2)], co-morbid clinical conditions and number of drugs. The comparisons were considered as statistically significant at p< 0.05. Results: Out of 476 patient data evaluated, a total of 781 drugs were prescribed. Among 190 patients who were prescribed two or more drugs, 35 (18.4%) patients had one or more pDDIs. We determined 48 (70.6%) C, 12 (17.6%) B, 7 (10.3%) D and 1 (1.5%) X risk category interactions. The most common pDDIs were between metformin and nonsteroidal anti-inflammatory drugs (7.4%). The presence of pDDIs was significantly associated with the number of prescribed drugs (p<0.001). Conclusion: The pDDIs in obesity outpatient clinic were relatively low. Nevertheless, in order to minimize DDIs, it is vital for physicians to be aware of the interactions between the frequently prescribed drugs in obesity outpatient clinic and monitor patients for the safe use of drugs.