Prevalence, Factors and Cost Comparison due to Potentially Inappropriate Medications (PIMs) of Elderly Outpatients in a State Hospital in Malaysia.

Abstract

Introduction: Malaysia will be a full aging nation by 2030. The elderly (aged >65 years old) population often has multiple comorbidities, which increases the risk of polypharmacy and potentially inappropriate medications (PIMs). This study aims to investigate the prevalence, factors associated with PIMs among elderly outpatients, and its burden of direct pharmacotherapy cost to the Ministry of Health Malaysia. Materials and method:  A cross-sectional study involving clinic prescriptions among the elderly with more than one-month prescribing duration received from a tertiary hospital specialist clinic pharmacy from March to April 2017. Patient identifiers were screened using the Pharmacy Information System (PhIS) by including prescriptions from other clinics while excluding multiple visits and duplicate prescriptions. Patients were categorised as PIM group and non-PIM groups using Beers Criteria 2015. Logistic regression analysis was conducted to examine the factors associated with PIMs. The median monthly prescription cost was compared between PIM and non-PIM groups by Mann-Whitney test. Results: Among 472 patients, 39.4% of patients had at least one PIM while 60.6% of patients did not receive any PIM. The number of medications prescribed was an independent risk factor contributing to PIMs (OR:2.04; 95% CI:1.40, 2.97). The median monthly prescription cost for the PIM group was MYR 29.50 (?USD 7.53) which was not statistically significant (p=0.735) compared with the non-PIM group which was MYR 28.50 (USD 7.28).  Conclusion: PIM was frequently prescribed in our setting with the number of medications as the only factor. However, the prescribing of PIM did not add nor reduce the direct cost of pharmacotherapy.