title: [Assessment of polypharmacy: A question of definition and underlying data].
abstract: BACKGROUND
  Older persons are often subjected to polypharmacy. There is a large degree of variability in the definitions used, the underlying data sources and the medications included. Our aim was to analyse the influence of different definitions on the prevalence of polypharmacy.
  
  
  METHODS
  We used data of the study "Inappropriate Medication in patients with REnal insufficiency in Nursing homes" (IMREN) conducted in nursing homes in Bremen and the surrounding area. Anonymised data were collected by nursing staff. Prescription drugs and over-the-counter drugs as well as scheduled and as-needed medications were assessed.
  
  
  RESULTS
  852 residents from 21 nursing homes were recruited (mean age: 83.5 years; 76.5% female). Each resident received an average of 8.8 scheduled and as-needed medications, the prevalence of polypharmacy (≥5 medications) was 83.5%. When including scheduled medications only, residents received an average of 6.3 medications (polypharmacy 69.7%). When restricting the analysis to prescription-only medicines, the results were comparable (6.3 medications per resident; polypharmacy 69.1%). However, the two analyses included different drugs. A total of 74.3% received at least one over-the-counter drug as scheduled medication (59.7% on an as-needed basis).
  
  
  CONCLUSIONS
  In studies investigating polypharmacy, the methods used should be reported in a transparent manner. This is particularly important when addressing the question of which drugs were included in the study.
authors.affiliation: Department für Versorgungsforschung, Fakultät für Medizin und Gesundheitswissenschaften Carl von Ossietzky Universität Oldenburg. Electronic address: falk.hoffmann@uni-oldenburg.de.
authors.forename: Falk
authors.initials: F
authors.lastname: Hoffmann
authors.affiliation: Abteilung Versorgungsforschung, Institut für Public Health und Pflegeforschung (IPP), Universität Bremen; Health Sciences Bremen, Universität Bremen, Bremen, Deutschland.
authors.forename: Guido
authors.initials: G
authors.lastname: Schmiemann
authors.affiliation: Department für Versorgungsforschung, Fakultät für Medizin und Gesundheitswissenschaften Carl von Ossietzky Universität Oldenburg.
authors.forename: Michael
authors.initials: M
authors.lastname: Dörks
mesh_terms: D000369:Aged, 80 and over; D000375:Aging; D005260:Female; D005858:Germany; D006801:Humans; D008297:Male; D009735:Nursing Homes; D061214:Patient Safety; D019338:Polypharmacy; D012307:Risk Factors; D012308:Risk Management
keywords: Arzneimitteltherapie; Health services research; Pflegeheim; Polypharmazie; Querschnittsstudie; Versorgungsforschung; cross-sectional study; nursing home; pharmacotherapy; polypharmacy