Evidence brief · July 2026
Medication non-adherence: its health and financial impact.
A concise interpretation of published evidence on failure to start, take or continue prescribed medicines. The figures describe population-level associations and modelled burden—not the consequence of every individual missed dose.
44%lower odds of death were associated with good medication adherence.
A meta-analysis of 21 observational studies involving 46,847 participants found a pooled odds ratio of 0.56 for mortality among people with good adherence compared with poor adherence.3 This is an association and does not prove that adherence alone caused the difference.
The scale
Non-adherence is common and multifactorial.
The World Health Organization reported that adherence to long-term therapies for chronic disease averages approximately 50% in developed countries.1 This is not simply forgetfulness: affordability, health literacy, treatment complexity, side effects, beliefs about medicine, cognitive or practical barriers and access to care can all contribute.
Effective support therefore needs to be personalised and non-judgemental. No single reminder, device or intervention will address every reason a person does not take a medicine as agreed.
Health outcomes
Association with poorer outcomes.
A meta-analysis of 21 observational studies covering 46,847 participants reported all-cause mortality of 8.5% among those classified as poorly adherent and 4.7% among those classified as adherent.3 The authors found an association; the study does not prove that adherence alone caused the difference.
| Evidence area | Published finding |
|---|---|
| All-cause mortality | Good adherence was associated with lower mortality than poor adherence across the included studies (pooled odds ratio 0.56; 95% CI 0.50–0.63).3 |
| Diabetes and heart disease | The OECD review reports mortality rates among non-adherent patients as nearly twice those of adherent patients.2 |
| Clinical deterioration | Non-adherence is associated with poorer disease control, complications and greater use of emergency and inpatient care.2,4 |
Economic burden
Avoidable use of healthcare resources.
The OECD estimated that poor medication adherence contributes to approximately €125 billion in avoidable hospitalisations, emergency care and outpatient visits in Europe each year.2 A systematic review also found substantial economic burden across disease groups, while noting major variation in study methods and cost estimates.4
How to interpret these figures
They are population-level estimates. They should not be used to assign a financial or clinical consequence to one person, one medicine or one missed dose.
Unequal circumstances
Rates are not evenly distributed.
Published rates vary by condition, medicine, population, time period and the definition used. A UK study conducted during the COVID-19 period found that 22.6% of adults with long-term conditions reported missing at least one medicine within seven days.5
Systematic reviews have reported relationships with age, sex and income in particular medicine groups, while US research has identified racial and ethnic inequalities in cost-related non-adherence among older adults.6–8 These characteristics should be understood as markers of unequal circumstances and barriers—not inherent causes.
What digital tools can do
Support routine and improve the record.
A reminder can address one practical barrier, but medication support is more useful when it also makes the regimen clear and records the actual outcome. A personal administration history can help the user recognise patterns and support a better-informed conversation with a pharmacist, prescriber or relative.
MediMAR is designed around that narrower role. It does not claim to solve non-adherence, improve clinical outcomes or replace professional support.
See how MediMAR goes beyond a pill reminder →Harvard-style bibliography
References.
- World Health Organization (2003) Adherence to long-term therapies: Evidence for action. Geneva: WHO. Available at: who.int/publications/i/item/9241545992 (Accessed: 31 July 2026).
- Khan, R. and Socha-Dietrich, K. (2018) ‘Investing in medication adherence improves health outcomes and health system efficiency’, OECD Health Working Papers, No. 105. Available at: doi.org/10.1787/8178962c-en (Accessed: 31 July 2026).
- Simpson, S.H. et al. (2006) ‘A meta-analysis of the association between adherence to drug therapy and mortality’, BMJ, 333, p. 15. Available at: doi.org/10.1136/bmj.38875.675486.55 (Accessed: 31 July 2026).
- Cutler, R.L. et al. (2018) ‘Economic impact of medication non-adherence by disease groups: a systematic review’, BMJ Open, 8, e016982. Available at: doi.org/10.1136/bmjopen-2017-016982 (Accessed: 31 July 2026).
- Dalton, K. et al. (2023) ‘What affected UK adults’ adherence to medicines during the COVID-19 pandemic?’, International Journal of Clinical Pharmacy, 45, pp. 118–129. Available at: doi.org/10.1007/s11096-022-01479-w (Accessed: 31 July 2026).
- Hope, H.F. et al. (2021) ‘Determinants of non-adherence to medications for dyslipidemia: a systematic review’, Patient Preference and Adherence, 15, pp. 1853–1871. Available at: doi.org/10.2147/PPA.S290216 (Accessed: 31 July 2026).
- Mann, D.M. et al. (2010) ‘Predictors of nonadherence to statins: a systematic review and meta-analysis’, Annals of Pharmacotherapy, 44(9), pp. 1410–1421. Available at: doi.org/10.1345/aph.1P150 (Accessed: 31 July 2026).
- Gellad, W.F. et al. (2007) ‘Race/ethnicity and nonadherence to prescription medications among seniors’, Journal of General Internal Medicine, 22, pp. 1572–1578. Available at: doi.org/10.1007/s11606-007-0385-z (Accessed: 31 July 2026).
Editorial and clinical scope
This evidence brief was prepared by MediMAR Ltd from the cited sources and reviewed for faithful representation of the published findings. It is not a systematic review, medical advice or evidence that MediMAR improves adherence or clinical outcomes.