POTENTIAL AND ACTUAL DRUG-DRUG INTERACTIONS AMONG PATIENTS WITH CARDIOVASCULAR DISEASE: A COMPREHENSIVE ANALYSIS OF DATA FROM A TERTIARY CARE HOSPITAL IN SOUTH INDIA

Context: Drug-drug interactions (DDIs) are frequently observed in hospitalized cardiac patients and associated with alteration in the effectiveness of cardiovascular therapy. Aim: The study was conducted to identify the incidence and nature of DDIs and their associated risk factors among patients with cardiovascular disease (CVD). Materials and Method: A prospective interventional study was conducted between August 2018 and April 2019 in the Department of Cardiology of a tertiary care South Indian hospital. Patients admitted with CVD on a minimum of two medications were enrolled in the study and their prescriptions were evaluated for DDIs using Micromedex interaction checker version 2.8. Results: A total of 258 patients with CVD were enrolled in the study with a mean age of 60.11±12.07 years. On average, each patient was prescribed 11.35±3.30 medications. The incidence of potential DDIs (pDDIs) was 99.61%, with 7.59±4.10 as a mean number of pDDIs per prescription. The majority of the interactions were significant in severity (50.69%), pharmacodynamic (68.24%) in nature, of unspecified onset (69.97%), and with fair documentation status (61.79%). The incidence of actual DDIs (aDDIs) was found to be 1.16%. The number of medications per prescription, duration of hospital stays, number and type of comorbidities, and presence of narrow therapeutic index drugs in the prescription were the significant risk factors for the occurrence of the higher number of interactions. Conclusion: The occurrence of a more significant number of DDIs in patients with CVD highlights the need for accurate monitoring, evaluation, and planning of the individual patients’ drug therapies.