Adherence: what it is and why it fails
- Concept
Adherence is how far what the patient does matches what was agreed with the care team; in chronic disease it is around one half.
What it is
WHO defines adherence as the extent to which a person's behaviour (taking medicines, following a diet or changing habits) matches the recommendations agreed with a health professional. It is preferred to ‘compliance’ because it implies agreement rather than obedience. According to WHO's 2003 report, only about 50 % of patients with chronic disease in developed countries are adherent, and fewer in developing countries. WHO groups the causes into five dimensions and stresses that responsibility does not lie with the patient alone.
The five dimensions of adherence (WHO 2003), with examples
| Dimension | Factors that worsen it |
|---|---|
| Social and economic | Poverty, cost, distance and transport, illiteracy, lack of social support, unstable housing |
| Health system and care team | Poor relationship, short visits, little education, no follow-up, barriers to access and to getting medicines |
| Condition | No symptoms, chronic course, depression, cognitive impairment, lack of insight |
| Therapy | Complex regimens, several doses a day, side effects, long duration, no immediate benefit |
| Patient | Forgetting, beliefs about the medicine, fear, low motivation, low self-efficacy, low health literacy |
Clinical notes
- In CDC Grand Rounds (2017), about 1 in 5 new prescriptions is never filled, and about half of those filled are taken incorrectly in timing, frequency or duration.
- Non-adherence increases complications, hospital admissions, antimicrobial resistance and costs.
- In hypertension, the lack of symptoms lowers perceived threat; in schizophrenia, lack of insight weighs heavily; in HIV and tuberculosis, poor adherence favours resistance.
In the lab
- Direct: blood or urine levels of the drug or a marker, and directly observed dosing.
- Indirect: self-report and questionnaires, pill counts, pharmacy refill records, electronic container monitors and clinical response.
- White-coat adherence improves in the days before a visit and fools one-off measurement.
- Clinicians overestimate their patients' adherence: asking without judgment beats assuming.
Test yourself
Think of the answer, then tap the question to see it.
Why is adherence preferred to compliance?
Adherence implies a plan agreed between patient and clinician; compliance suggests passive obedience to an order.
What are WHO's five dimensions of adherence?
Social and economic, health system and care team, condition-related, therapy-related and patient-related.
What is white-coat adherence?
A temporary improvement in adherence in the days before a visit, which makes one-off measurements overestimate it.
Roughly what adherence to long-term therapy did WHO report for developed countries?
About 50 %, and lower in developing countries.
Elsewhere in DurgiPedia
Connections
Educational content on behavior and the clinical relationship; not a diagnostic or treatment guide and no substitute for assessment by a health professional. If you or someone near you is at risk, seek help now from an emergency service or a mental-health helpline.
Sources: Failure to take prescribed medicine for chronic diseases is a massive, world-wide problem (World Health Organization, 2003); CDC Grand Rounds: Improving Medication Adherence for Chronic Disease Management — Innovations and Opportunities (Centers for Disease Control and Prevention (MMWR), 2017); Theory at a Glance: A Guide For Health Promotion Practice (Second Edition) (National Cancer Institute, National Institutes of Health (US), 2005).
Spotted a mistake?We are always improving for the community. Tell us what is wrong and our team will review it.Report a mistake
Representative model, for educational purposes only.