Drugs & Aging

, Volume 28, Issue 7, pp 547–560

Variation Over Time in the Association between Polypharmacy and Mortality in the Older Population

  • Kathryn Richardson
  • Alexandrine Ananou
  • Louise Lafortune
  • Carol Brayne
  • Fiona E. Matthews
Original Research Article

DOI: 10.2165/11592000-000000000-00000

Cite this article as:
Richardson, K., Ananou, A., Lafortune, L. et al. Drugs Aging (2011) 28: 547. doi:10.2165/11592000-000000000-00000

Abstract

Background: In the older population, multimorbidity is common and ‘best practice’ may invite the prescription of multiple medications.

Objective: To examine the association between polypharmacy, defined as the concurrent use of five or more prescription or nonprescription medications, and mortality in 12 423 participants aged ≥65 years representative of the older population of England and Wales.

Methods: Data on self-reported medication use, disability and health conditions were collected at baseline in 1991–3. The cohort was followed for up to 18 years with full mortality notification. Cox proportional hazards regression adjusted for age, baseline institutionalization, smoking, disability and health conditions was used to investigate polypharmacy and mortality, stratified by sex. Various methods for modelling the time-varying effect of polypharmacy are presented.

Results: A strong independent association between polypharmacy and mortality existed in the short-term (first 2 years) for both men and women. This association remained, although attenuated, in the medium-long term (2–18 years of follow-up) for women, but became non-significant in the longer term for men.

Conclusions: It remains unclear whether polypharmacy is a marker for poor health or is an independent risk factor for mortality. However, polypharmacy strongly predicts adverse outcomes, and multiple medication use should therefore be carefully monitored in the older population.

Copyright information

© Adis Data Information BV 2011

Authors and Affiliations

  • Kathryn Richardson
    • 1
    • 2
  • Alexandrine Ananou
    • 3
  • Louise Lafortune
    • 1
  • Carol Brayne
    • 1
    • 3
  • Fiona E. Matthews
    • 4
  1. 1.Institute of Public HealthUniversity of CambridgeCambridgeUK
  2. 2.The Irish Longitudinal Study on Ageing, Department of Medical GerontologyTrinity College DublinDublin 2Ireland
  3. 3.Department of Public Health and Primary CareUniversity of CambridgeCambridgeUK
  4. 4.Medical Research Council Biostatistics UnitCambridgeUK