Advertisement

International Journal of Clinical Pharmacy

, Volume 36, Issue 1, pp 15–19 | Cite as

Challenges in measuring medication adherence: experiences from a controlled trial

  • Kay StewartEmail author
  • Kevin P. Mc Namara
  • Johnson George
Commentary

Abstract

Measurement of adherence is complex and many methods, both direct and indirect are used; there is no universal gold standard. In this article, we share our experiences in a randomised controlled study, the Hypertension Adherence Program in Pharmacy trial, evaluating a community pharmacy-based intervention for improving adherence to antihypertensive medication. Several objective and subjective measures of adherence (Morisky score, TABS score, MedsIndex, Medicines Possession Ratio) were used, but produced varying results, limiting confidence in the conclusions that could be drawn. Despite using a specifically designed data mining software program to identify potentially nonadherent patients from dispensing records, many participants were found to be adherent by the self reported Morisky scale. A lesson to be learned when targeting people for interventions to improve adherence is that information from dispensing records should be supplemented by other methods in order to identify patients most in need of assistance.

Keywords

Medication adherence Adherence measures Randomised controlled trial 

Notes

Acknowledgments

We acknowledge the other researchers on the HAPPy trial: Michael J. Bailey, Rosalind Lau, Jenny McDowell (Monash University), Diana Bortoletto (Monash University; Barwon Health); Shane L. Jackson, Gregory M. Peterson, Luke Bereznicki, Peter Gee (University of Tasmania); Jeffery D. Hughes (Curtin University); Ya-Seng (Arthur) Hsueh (The University of Melbourne).

Funding

The HAPPy Trial was funded by the Australian Government Department of Health and Ageing through the Fourth Community Pharmacy Agreement Research & Development Grants Program managed by The Pharmacy Guild of Australia.

Conflicts of interest

The authors declare no conflict of interests.

References

  1. 1.
    Sabaté E. World Health Organization. Adherence to long-term therapies: evidence for action. 2003. Geneva: World Health Organisation, 2003. http://www.who.int/chp/knowledge/publications/adherence_full_report.pdf. Accessed August 2013.
  2. 2.
    Farmer K. Methods for measuring and monitoring medication regimen adherence in clinical trials and clinical practice. Clin Ther. 1999;21(6):1074–90.PubMedCrossRefGoogle Scholar
  3. 3.
    Lau R, Stewart K, Mc Namara K, Jackson SL, Hughes JD, Peterson GM, et al. Evaluation of a community pharmacy-based intervention for improving patient adherence to antihypertensives: a randomized controlled trial. BMC Health Serv Res. 2010;10(1):34.PubMedCentralPubMedCrossRefGoogle Scholar
  4. 4.
    Nelson MR, Reid CM, Ryan P, Willson K, Yelland L. Self-reported adherence with medication and cardiovascular disease outcomes in the Second Australian National Blood Pressure Study (ANBP2). MJA. 2006;185(9):487–9.PubMedGoogle Scholar
  5. 5.
    Bramley TJ, Gerbino PP, Nightengale BS, Frech-Tamas F. Relationship of blood pressure control to adherence with antihypertensive monotherapy in 13 managed care organizations. J Manag Care Pharm. 2006;12(3):239–45.PubMedGoogle Scholar
  6. 6.
    Ho PM, Magid DJ, Masoudi FA, McClure DL, Rumsfeld JS. Adherence to cardioprotective medications and mortality among patients with diabetes and ischemic heart disease. BMC Cardiovasc Disord. 2008;6:48. doi: 10.1186/1471-2261-6-48.CrossRefGoogle Scholar
  7. 7.
    Osterberg L, Blaschke T. Adherence to medication. N Engl J Med. 2005;353(5):487–97.PubMedCrossRefGoogle Scholar
  8. 8.
    Chapman RH, Benner JS, Petrilla AA, Tierce JC, Collins SR, Battleman DS, et al. Predictors of adherence with antihypertensive and lipid-lowering therapy. Arch Intern Med. 2005;165(10):1147–52.PubMedCrossRefGoogle Scholar
  9. 9.
    Vrijens B, Vincze G, Kristant P, Urquhart J, Burnier M. Adherence to prescribed antihypertensive drug treatments: longitudinal study of electronically compiled dosing histories. BMJ. 2008;336:1114–7.PubMedCrossRefGoogle Scholar
  10. 10.
    Simons LA, Ortiz M, Calcino G. Persistence with antihypertensive medication: Australia-wide experience, 2004–2006. MJA. 2008;188(4):224–7.PubMedGoogle Scholar
  11. 11.
    Cramer JA, Roy A, Burrell A, Fairchild CJ, Fuldeore MJ, Ollendorf DA, et al. Medication compliance and persistence: terminology and definitions. Value Health. 2008;11(1):44–7.PubMedCrossRefGoogle Scholar
  12. 12.
    Briganti EM, Shaw JE, Chadban SJ, Zimmet PZ, Welborn TA, Mcneil JJ, Atkins RC. Untreated hypertension among Australian adults: the 1999–2000 Australian Diabetes, Obesity and Lifestyle Study (AusDiab). MJA. 2003;179(3):135–9.PubMedGoogle Scholar
  13. 13.
    Janus ED, Bubker SJ, Kilkkinen A, Mc Namara KM, Philpot B, Tideman P, et al. Prevalence, detection and drug treatment of hypertension in a rural Australian population: the Greater Green Triangle Risk Factor Study 2004-2006. Intern Med J. 2008;38:879–86.PubMedCrossRefGoogle Scholar
  14. 14.
    Brown MJ, Cruickshank JK, Dominiczak AF, MacGregor GA, Poulter NR, Russell GI, et al. Better blood pressure control: how to combine drugs. J Hum Hypertens. 2003;17(2):81–6.PubMedCrossRefGoogle Scholar
  15. 15.
    Burnier M. Medication adherence and persistence as the cornerstone of effective antihypertensive therapy. Am J Hypertens. 2006;19(11):1190–6.PubMedCrossRefGoogle Scholar
  16. 16.
    Morisky DE, Green LW, Levine DM. Concurrent and predictive validity of a self-reported measure of medication adherence. Med Care. 1986;24(1):67–74.PubMedCrossRefGoogle Scholar
  17. 17.
    George J, Mackinnon A, Kong DC, Stewart K. Development and validation of the beliefs and behaviour questionnaire (BBQ). Patient Educ Couns. 2006;64:50–60.PubMedCrossRefGoogle Scholar
  18. 18.
    Pharmacy Guild of Australia. MedsIndex: a medicines compliance indicator. Canberra: The Pharmacy Guild of Australia, 2008. http://www.guild.org.au/iwov-resources/documents_members/The_Guild/tab-Business_Support/eHealth_and_IT_Tools/MedsIndex/PGA1596_02A_MedsIndex_Brochure_Final.pdf. Accessed June 2013.
  19. 19.
    Steiner JF, Prochazka AV. The assessment of refill adherence using pharmacy records, methods, validity and application. J Clin Epidemiol. 1997;50(1):105–16.PubMedCrossRefGoogle Scholar

Copyright information

© Koninklijke Nederlandse Maatschappij ter bevordering der Pharmacie 2013

Authors and Affiliations

  • Kay Stewart
    • 1
    Email author
  • Kevin P. Mc Namara
    • 1
    • 2
    • 3
  • Johnson George
    • 1
  1. 1.Centre for Medicine Use and SafetyMonash University (Parkville Campus)ParkvilleAustralia
  2. 2.Greater Green Triangle University Department of Rural HealthFlinders UniversityAdelaideAustralia
  3. 3.Greater Green Triangle University Department of Rural HealthDeakin UniversityWarrnamboolAustralia

Personalised recommendations