A Study on Polypharmacy in the Elderly Psychiatric Outpatients with Persistent Treatments for 3 years

Yoo, Hae Sun; Jung, In Kwa

Abstract

OBJECTIVES
The objective of this study was to investigate the prescription trends for the elderly psychiatric outpatients at a university hospital.
METHODS
We performed a retrospective study based on medical records. Data on 146 elderly patients (65 years and older) diagnosed with psychiatric disorders according to ICD-10 from January 2005 to March 2008 were collected. Analyses were performed regarding demographic characteristics, prevalence of polypharmacy, and the doses and types of drugs prescribed.
RESULTS
In 146 subjects, the mean age was 76.14+/-5.21. More than five types of drugs were prescribed to 49.5% of the patients in 2008. The percentage of stable users (those without changes in the category of polypharmacy for 3 years) was 69.8%. Each patient received an average of 4.20+/-1.50 kinds of drugs in 2005 and 4.02+/-1.77 in 2008. The average dose of drugs was 6.1+/-3.50 in 2005 and 6.49+/-4.09 in 2008, and the difference was not statistically significant. The average number of types of psychiatric drugs prescribed to the patients decreased from 2.37+/-0.86 in 2005 to 2.17+/-0.87 in 2008 (p<0.05).
CONCLUSION
Although practice of polypharmacy showed a slow increase over the 3 years from 2005 to 2008, almost half of the elderly patients we studied received multiple drugs. Since polypharmacy can increase drug-drug interactions and adverse effects in the elderly, appropriate drug monitoring and careful prescription are necessary.