Overview
This lecture defines treatment adherence and distinguishes it from compliance, then quantifies how often adherence actually happens across acute illness, chronic illness and lifestyle change. It traces where adherence is lost along the medication pathway, sets out the consequences of non-adherence for four stakeholders (patient, whānau, doctor, healthcare system), classifies the causes using the WHO’s Five Dimensions of Adherence, and finishes with the clinician-side strategies that act on those causes. The parts fit together as a chain: what adherence is, how often it fails, why that matters, what drives it, and what a doctor can do about it.
Course context and links
- Sits in the ELM 2 Psychological Medicine Block, within the Medical Psychology component. The block runs Medical Psychology, then Mental Disorders, then Human Development; a Psychological Medicine Vertical Module runs across both ELM 2 and ELM 3.
- Linked material: Personality and Health Behaviour module; Motivational Interviewing lecture; Health Behaviour Change lecture; Behavioural addictions lecture; ELM 2 Case 2 (Health And Illness Behaviour).
Learning objectives
- Understand what treatment adherence is.
- Learn how frequently adherence occurs.
- Describe consequences of non-adherence.
- Name factors that influence adherence.
- Learn strategies to enhance adherence for patients.
What treatment adherence is
Key points:
- Definition: congruency between behaviour and agreed health recommendations.
- Adherence ≠ compliance.
- Adherence is an active choice and responsibility.
- Compliance is a passive behaviour of following the doctor’s orders.
- Adherence sits on the causal path between treatment and outcome: treatment feeds into adherence, and adherence feeds into outcome. Treatment therefore only produces an outcome through the patient’s adherence.
- Adherence increases in the days before and after a doctor’s visit.
How frequent adherence is
Adherence rates by context:
| Context | Adherence rate |
|---|---|
| Acute illness | 67% |
| Chronic illness | 50–55% |
| Lifestyle change — diet | 13–76% |
| Lifestyle change — exercise | 65–90% |
Diabetes specifically:
- 20–40% follow diet and physical activity recommendations.
- 65–70% monitor blood glucose as recommended.
Other reported figures:
- 50% of patients aged 65 years and older do not take their medications as prescribed.
- 125,000 premature deaths in the U.S. each year result from non-adherence.
- $300 billion in avoidable costs to the U.S. healthcare system annually.
- $637 billion in annual cost to the pharmaceutical industry globally.
Where adherence is lost — the medication pathway
Adherence falls stepwise along the route from prescribing to continued use:
- Provider’s office — meds prescribed: 100%
- Pharmacy — meds filled: 88%
- At home — meds not taken: 76%
- At home — meds discontinued: 47%
Important
Losses occur at every step, but the largest single drop is at home after dispensing — so a filled prescription is not evidence of adherence.
Warning
One statistic on the healthcare-system costs slide is cropped: a heading reading ”…ARE NON-ADHERENT” has its leading words cut off the slide, so the figure it refers to is not visible.
Consequences of non-adherence
Discussed for four stakeholders.
For the patient:
- Worsen the patient’s health condition
- Increase risk of disease progression and complications
- Reduce effectiveness of treatment
- Delayed recovery
- Prolonged hospitalisation
- Increased medical cost
- Reduced quality of life
For the whānau (family):
- Caregiver burden — time, distress, relationship strain
- Financial burden
For the doctor:
- Increased workload → burnout
- Distrust and resentment toward the patient
- Give-up
- Blaming the patient → reinforcing stereotypes
For the healthcare system:
- Increased healthcare cost and resources
- Longer waiting list
- Reduced time to improve healthcare and for professional development
WHO’s Five Dimensions of Adherence
The five dimensions, arranged clockwise in the WHO model, with the factors given for each:
1. Social & Economic
- Limited English proficiency
- Limited access to healthcare
- Financial barriers
- Cultural beliefs
2. Health Care System
- Provider–patient relationship
- Health inequity
- Long wait times
- Lack of positive reinforcement from provider
3. Condition-Related
- Chronic conditions
- Lack of symptoms
- Depression
- Neurodevelopmental difficulties
4. Therapy-Related
- Complex medication regimen
- Changes in medication regimen
- Unpleasant side effects
- Interference with lifestyle
5. Patient-Related
- Cognitive impairment
- Beliefs about health/treatment
- Fear of dependency
- Frustration with health provider
Strategies for managing adherence
Starting stance
- Consider every patient to be at risk for non-adherence.
- Consider every patient to encounter barriers to treatment adherence.
The mechanism driving adherence
Adherence is presented as a set of interlocking cogs: six contributing factors turn one another and ultimately drive adherence.
- Memory support
- Routine
- Practical and emotional support
- Past experiences with healthcare & treatment
- Belief in and experience of benefits
- Purpose
Three clinician levers act on this system: the doctor-patient relationship, Stages of Change, and Motivational Interviewing.
Clinician actions, paired to the mechanism
Acting on past experiences, beliefs and purpose (via the doctor–patient relationship, stages of change and motivational interviewing):
- Assess stages of change
- Assess past adherence patterns and current beliefs and concerns about treatment
- Have the patient rate their confidence in carrying out treatment
- Identify barriers
Acting on memory support, routine and practical/emotional support:
- Prompts and reminders
- Treatment education
- Regular follow-up visits with the patient
- Continue to assess adherence and barriers to adherence
- Refer to other health professionals — social worker, Health Improvement Practitioners, etc.
Patient-facing tools shown
- Medication-reminder apps: Medisafe (Medication Management — Pill and Medicine Reminder; lock screen widget, 70+ symptom trackers, works with Apple Health) and MyTherapy (Medication Reminder — Pill Tracker & Med Alarm; intake tracking, symptom/well-being patterns, health diary with PDF printout, inventory tracking and refill reminders).
- CardioSmart patient poster: skipping, changing or ignoring your medicine can be bad for your health; take your medicine in the right doses, at the right time, the right way. Helpful tips — use a weekly pillbox; create reminders with notes or alarms; ask your care team whether to take medicine with or without food; bring a list of all your medicines to every health visit.
- A four-photo demonstration sequence captioned “A–C: Medicine controlling virus inside the body” and “D: virus still present next day”.
Warning
This slide is a collage of third-party graphics with no lecturer commentary text, so the intended teaching point is not stated on the slide. The smallest disclaimer and app-store rating lines are not fully legible.
Summary
- Treatment adherence is an active choice and responsibility to follow the recommended treatment.
- Non-adherence is common across health conditions and lifestyle changes, e.g. chronic illness: 50–55% treatment adherence.
- Non-adherence can negatively impact the patient, their whānau, the doctor, and the healthcare system.
- WHO’s five dimensions of adherence: social & economic, healthcare system, condition-related, therapy-related, patient-related.
- There are many ways for you as a doctor to improve your patient’s adherence: support & reminders, understanding experience and beliefs, treatment education, and building a good doctor–patient relationship.
Warning
On the summary slide the final numbered item is numbered “1)” rather than “5)”.
Self-test
- Define treatment adherence.
- Distinguish adherence from compliance.
- Describe where adherence sits in the relationship between treatment and outcome.
- State the treatment adherence rates given for acute illness and for chronic illness.
- Give the adherence ranges reported for diet and for exercise as lifestyle changes.
- List the two diabetes-specific adherence figures given.
- Describe the four steps of the medication pathway and the adherence percentage at each.
- Explain why a filled prescription is a poor indicator that a patient is adhering.
- List the consequences of non-adherence for the patient.
- List the consequences of non-adherence for the whānau.
- List the consequences of non-adherence for the doctor.
- List the consequences of non-adherence for the healthcare system.
- Name the five dimensions of the WHO model of adherence.
- Give two factors under the Social & Economic dimension.
- Give two factors under the Health Care System dimension.
- Give two factors under the Condition-Related dimension.
- Give two factors under the Therapy-Related dimension.
- Give two factors under the Patient-Related dimension.
- State the two assumptions a clinician should start from when managing adherence.
- List the six contributing factors that drive adherence in the cog model.
- Name the three clinician levers that act on the adherence mechanism.
- List the assessment actions paired with past experiences, beliefs and purpose.
- List the clinician actions paired with memory support, routine and practical/emotional support.
- Explain why “lack of symptoms” makes a condition harder to adhere to treatment for, using the cog model.
- A patient with type 2 diabetes has limited English, waits a long time for appointments, is on a recently changed multi-drug regimen with unpleasant side effects, and does not believe the medicines are helping. Classify each of these four barriers by WHO dimension.
- A 70-year-old on four medications reports that they fill their prescriptions but “lose track” during the week and stopped one tablet after a month because they felt no different. Predict which cogs are failing and name a matching intervention for each.
- Integrative: explain how non-adherence in one patient can propagate into consequences for the doctor and the healthcare system.
- Explain why adherence measured immediately after a clinic visit may overestimate a patient’s usual adherence.
Answers
Reveal answers
- Congruency between behaviour and agreed health recommendations.
- Adherence is an active choice and responsibility; compliance is a passive behaviour of following the doctor’s orders.
- Treatment feeds into adherence, and adherence feeds into outcome — adherence is the intermediate step on the path from treatment to outcome.
- Acute illness 67%; chronic illness 50–55%.
- Diet 13–76%; exercise 65–90%.
- 20–40% follow diet and physical activity recommendations; 65–70% monitor blood glucose as recommended.
- Prescribed at the provider’s office 100%; filled at the pharmacy 88%; not taken at home 76%; discontinued at home 47%.
- Because adherence continues to fall after dispensing — from 88% filled to 76% actually taken and 47% once discontinuation at home is counted.
- Worsened health condition; increased risk of disease progression and complications; reduced treatment effectiveness; delayed recovery; prolonged hospitalisation; increased medical cost; reduced quality of life.
- Caregiver burden (time, distress, relationship strain) and financial burden.
- Increased workload leading to burnout; distrust and resentment toward the patient; giving up; blaming the patient, which reinforces stereotypes.
- Increased healthcare cost and resources; longer waiting lists; reduced time to improve healthcare and for professional development.
- Social & Economic; Health Care System; Condition-Related; Therapy-Related; Patient-Related.
- Any two of: limited English proficiency; limited access to healthcare; financial barriers; cultural beliefs.
- Any two of: provider–patient relationship; health inequity; long wait times; lack of positive reinforcement from provider.
- Any two of: chronic conditions; lack of symptoms; depression; neurodevelopmental difficulties.
- Any two of: complex medication regimen; changes in medication regimen; unpleasant side effects; interference with lifestyle.
- Any two of: cognitive impairment; beliefs about health/treatment; fear of dependency; frustration with health provider.
- Consider every patient to be at risk for non-adherence, and consider every patient to encounter barriers to treatment adherence.
- Memory support; routine; practical and emotional support; past experiences with healthcare & treatment; belief in and experience of benefits; purpose.
- The doctor–patient relationship, stages of change, and motivational interviewing.
- Assess stages of change; assess past adherence patterns and current beliefs and concerns about treatment; have the patient rate their confidence in carrying out treatment; identify barriers.
- Prompts and reminders; treatment education; regular follow-up visits; continued assessment of adherence and barriers; referral to other health professionals such as social workers and Health Improvement Practitioners.
- Without symptoms the patient does not experience benefit from the treatment, so the “belief in and experience of benefits” cog — and with it purpose — fails to drive the rest of the mechanism.
- Limited English proficiency — Social & Economic; long wait times — Health Care System; recently changed complex regimen with unpleasant side effects — Therapy-Related; belief that the medicines are not helping — Patient-Related.
- Losing track during the week points to failures of memory support and routine, addressed with prompts and reminders (e.g. a weekly pillbox, alarms or a reminder app); stopping a tablet because they felt no different points to belief in and experience of benefits, addressed by treatment education and by assessing beliefs and concerns about treatment within the doctor–patient relationship.
- The patient’s condition worsens and recovery is delayed, prolonging hospitalisation and repeat contact; this increases the doctor’s workload, risking burnout, distrust and blaming of the patient; the extra consultations, admissions and resources raise system costs and lengthen waiting lists, reducing time available to improve healthcare and for professional development.
- Because adherence increases in the days before and after a doctor’s visit, so a measurement taken then is not representative of everyday behaviour.