Medication adherence in healthy elders: small cognitive changes make a big difference

J Aging Health. 2009 Jun;21(4):567-80. doi: 10.1177/0898264309332836. Epub 2009 Apr 1.


Objective: This was a cross-sectional study of the ability of independently living healthy elders to follow a medication regimen. Participants were divided into a group with High Cognitive Function (HCF) or Low Cognitive Function (LCF) based on their scores on the ADAS-Cog.

Method: Thirty-eight participants aged 65 or older and living independently in the community followed a twice-daily vitamin C regimen for 5 weeks. Adherence was measured using an electronic 7-day pillbox.

Results: The LCF group had significantly poorer total adherence than the HCF group (LCF: 63.9 +/- 11.2%, HCF: 86.8 +/- 4.3%, t( 36) = 2.57, p = .007), and there was a 4.1 relative risk of non-adherence in the LCF group as compared to the HCF group.

Discussion: This study has important implications for the conduct of clinical drug trials, as it provides strong evidence that even very mild cognitive impairment in healthy elderly has a detrimental impact on medication adherence.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Activities of Daily Living
  • Aged
  • Aged, 80 and over
  • Ascorbic Acid / therapeutic use
  • Cognition Disorders / psychology*
  • Cognition*
  • Cross-Sectional Studies
  • Female
  • Geriatric Assessment
  • Health Status
  • Humans
  • Male
  • Medication Adherence / psychology
  • Medication Adherence / statistics & numerical data*
  • Oregon
  • Psychiatric Status Rating Scales
  • Self Administration
  • Self Care


  • Ascorbic Acid