Adherence, Compliance & Concordance Notes

Adherence, Compliance & Concordance

Learning Outcomes

  • Understand definitions: adherence, compliance, and concordance.
  • Differentiate types of non-adherence.
  • Measure adherence/compliance.
  • Describe consequences of non-adherence and associated economic/societal costs.
  • Explain factors influencing adherence behavior.
  • Identify effective interventions for improving adherence/compliance.

Key Terms

  • Compliance/Non-compliance: Alignment with prescriber’s instructions.
  • Adherence/Non-adherence: How well the patient follows treatment recommendations.
  • Concordance/Non-concordant: Partnership approach in patient-physician decision-making.
  • NICE Guidance on Medicines Adherence: Reference for adherence strategies (https://www.nice.org.uk/guidance/cg76).

Compliance

  • Definition: Acting according to a request or demand, matching behavior with prescriber instructions.

Adherence

  • Definition: The extent to which individuals reciprocate healthcare recommendations (WHO, 2003).
    • Includes medication intake, diet, lifestyle changes.

Concordance

  • Definition: Collaborative relationship emphasizing negotiation and shared decision-making in treatment goals.

Types of Non-Adherence

  • Primary Non-Adherence: Failing to start medication after it has been prescribed.
  • Non-Persistence: Stopping medication after starting without advice.
  • Non-Conforming: Deviating from prescribed medication regimens (skipping doses, incorrect timings/doses, etc.).
  • Intentional Non-Adherence: Choosing to stop due to side effects/beliefs.
  • Unintentional Non-Adherence: Forgetting to take medication or not adhering to schedules.

Measuring Compliance/Adherence

Self-Report
  • Ranges from simple to complex assessments of missed doses.
    • Pros: Low-cost, easy to implement.
    • Cons: Subject to biases (social desirability, memory).
  • Stirratt et al (2015): Recommendations on optimal use of self-report measures.
Pill Counts
  • Tracking unused pills at visits to match expected counts based on prescribed doses.
    • Pros: Inexpensive.
    • Cons: Potential for abuse (pill renting schemes).
  • Viscomi et al (2013): Pill counts as an unintended entrepreneurial opportunity.
Drug Concentrations
  • Measurement of drug levels in blood; more intrusive and expensive.
    • Cons: Variable metabolic rates can affect accuracy.
  • Lam and Fresco (2015): Overview of medication adherence measures.

Prevalence of Non-Adherence

  • Common in chronic diseases such as asthma, depression, diabetes, epilepsy, and hypertension.
  • 30% to 50% of patients fail to properly adhere (WHO, 2003).

Consequences of Non-Adherence

  • Poor health-related quality of life.
  • Increased hospitalizations.
  • Premature mortality.
  • Increased NHS costs.

Wider Economic and Societal Costs

  • Increased healthcare expenditure (e.g., for avoidable hospitalizations).
  • Social care costs (e.g., long-term care).
  • Criminal justice costs linked to non-adherence in mental health cases.
  • Development of drug resistance due to inconsistent medication usage.

Factors Influencing Adherence Behavior

  • Patient-Related: Beliefs, comorbidities, demographics, and understanding of condition.
  • Therapy-Related: Complexity of regimens and side effects.
  • System-Related: Challenges with medication packaging and prescription costs.
  • Practitioner-Related: Importance of supporting informed choices and shared decision-making.

Interventions for Improving Adherence

Medication Education
  • Providing clear verbal/written information.
  • In-patient self-administration programs.
Improving Convenience
  • Simplifying dosing schedules.
  • Linking regimens to daily habits.
  • Using multi-compartment devices (e.g., Dosett boxes).
Enhancing Labelling/Packaging
  • Addressing sensory impairments (e.g., braille labels, bottles without child-resistant caps).
Providing Prompts and Reminders
  • Personalized reminders through charts, phone calls, and refill prompts.

Summary

  • Key areas explored include:
    • Definitions and Importance of adherence, compliance, and concordance.
    • Types and measurement of non-adherence.
    • The consequences and broader implications of non-adherence.
    • Factors influencing adherence behaviors and strategies for improving compliance.

Any Questions?