Prescribing pattern, polypharmacy and potentially inappropriate prescribing in hospitalized elderly patients: a retrospective study in a teaching hospital in Nepal

Background: Evaluate prescribing pattern, polypharmacy, and prescribing potentially inappropriate medicine (PIM) in elderly population to contribute in awareness towards rational use of drugs. Methods: A retrospective cross-sectional and observational study was done in hospitalized geriatric patients in Nepal. The World Health Organization (WHO) “core prescribing indicators” and Beers' 2012 updated criteria were used to assess prescribing pattern and inappropriate prescribing respectively. The drug- drug interactions were checked using Medscape drug interaction checker. In addition, disease prevalence and the most commonly prescribed drugs were also assessed where diseases and drugs were classified according to International Classification of Diseases-10 (ICD-10) and the Anatomical Therapeutic Chemical (ATC) classification respectively. Results: Out of 225 patients, 118 (52.4%) were males and most of the patients were in the age group 65-74 years (125, 55.6%). The diseases of circulatory system were more prevalent (135, 60%) and the average number of drugs was 8.19±3.50. Generic name prescribing was 8.51% and 77.33% of prescription contained antibiotic(s). Injection(s) prescribed were 80%, and drugs prescribed from national essential drug list and WHO essential drug list were 52.55% and 46.15% respectively. Medicines for alimentary tract and metabolism (215, 95.55%) and cardiovascular system (155, 68.89%) were most frequently prescribed. Polypharmacy (≥5 drugs) was found in 195 (86.66%) patients and was significant (P= 0.001). The potentially inappropriate medicines (PIMs) prescribed were 133 (7.21%) and at least one PIM was prescribed to 78 (34.67%) patients. Almost half numbers of patients (48.9%) were detected with at least one potential drug-drug interaction (DDI). Conclusions: Majority of hospitalized elderly patients received polypharmacy with drugs which may have serious drug-drug interactions. Thus, less number of drugs per prescription with minimum potential of drug-drug interaction and inappropriate medicines for elderly can be reinforced by implementing proper system of recording and analysing the therapy.