Physicians' prescription behavior of potentially inappropriate medications for elderly people: an analysis using the PRISCUS list based on TK routine data

Background: Referring to the German PRISCUS list, the paper analyzes differences in the prescription of potentially inadequate medication (PIM) between older and younger patients. We account for changes in the development over time and for the influence of the publication of the PRISCUS list. Methods: The retrospective study analyzes pharmaceutical prescriptions based on data from the Techniker Krankenkasse for the years 2008-20012. Age groups are compared regarding PIM prescriptions as share of total prescriptions within therapeutic areas (based on ATC codes). For a comparison of prescribed daily doses between age groups the median of those younger than 65 was indexed to the value 100. Results: The share of older insured with at least one PRISCUS prescription declined from 21,7 % in 2008 to 18,9 % in 2012. Moreover, the total share of PIM prescriptions is steadily higher for elderly persons. Comparing major therapeutic areas shows a heterogeneous picture. An influence of the PRISCUS list on the prescription behavior is not observable. Conclusion: The share of PIM prescriptions in the TK sample is slightly declining over time. Unexpectedly, the total share is higher for the elderly than for those below 65. With regard to different therapeutic areas, results are less clear. For future research, our findings emphasize the need to rely on the applied methods.