Assessment of polypharmacy in elderly patients by using data from dispensed medications in community pharmacies: analysis of results by using different methods of estimation
Background Estimating the prevalence of polypharmacy is essential for the evaluation of public health. Many different methodologies are used to determine the number of drugs used by a patient. Objective To analyse and compare three different methods (simultaneous, cumulative and continuous medication) to determine the number of drugs used by a patient, to estimate the prevalence of polypharmacy and to evaluate the possible association between polypharmacy and the gender and age of patients. Method Cross-sectional observational study carried out between April and September 2015. Data were acquired from prescriptions corresponding to 3972 patients aged 65 years old or older in ten community pharmacies in Argentina. Results The prevalence of polypharmacy varied significantly according to the method used. Major polypharmacy (use of five or more drugs) was detected in 20.5–47.1% of the patients. The association between gender, age and polypharmacy was statistically significant only when using the continuous medication method. The prevalence of minor polypharmacy (use of two to four drugs) was similar with the three methods. Conclusion These results contribute to deciding which is the best method to determine polypharmacy according to the objective of future studies and considering the advantages and disadvantages of each of them.
KeywordsCommunity pharmacy Drug utilization Elderly Methodology Polypharmacy Potentially inappropriate medication
This study was supported by Universidad Nacional de Rosario (No 445/2015) and a grant from Secretaría de Estado de Ciencia, Tecnología e Innovacion -SECTEI- (No 2010-174-14), Santa Fe, Argentina.
Conflicts of interest
Luciana Chiapella, Jorgelina Montemarani Menna and María Eugenia Mamprin report no conflict of interest in the conduction of this study or the preparation of this manuscript.
- 1.Wade O. Concept of drug utilization studies. In: Bergman U, Grimsson A, Wahba A, Westerholm B, editors. Studies in drug utilization. Copenhagen: WHO Regional Office for Europe; 1979. p. 3–15.Google Scholar
- 3.Monégat M, Sermet C, Perronnin M, Rococo E. Polypharmacy: definitions, measurement and stakes involved review of the literature and measurement tests. Questions d’économie de la santé. 2014;214:1–8.Google Scholar
- 5.World Health Organization. 2018. http://www.who.int/topics/pharmaceutical_products/en/. Accessed 28 Feb 2018.
- 6.WHO Collaborating Centre for Drug Statistics Methodology. Guidelines for ATC classification and DDD assignment 2016. 19 ed. Oslo, Norway: 2015.Google Scholar
- 10.Hofer-Dueckelmann C. Gender and polypharmacotherapy in the elderly: a clinical challenge. In: Sex and Gender Differences in Pharmacology; 2013. p. 169–182.Google Scholar