The World Health Organization (WHO) defines adherence as “the extent to which a person’s behaviour—taking medication, following a diet, and/or executing lifestyle changes—corresponds with agreed recommendations from a healthcare provider”. This definition highlights a collaborative approach between the patient and provider, emphasizing that the treatment plan is mutually acceptable. The concept of adherence has evolved from the older, more paternalistic term 'compliance' to reflect a shift towards patient-centered care and shared decision-making.
Adherence vs. Compliance: Understanding the Difference
While the terms 'adherence' and 'compliance' were once used interchangeably, modern healthcare distinguishes between them to better reflect the patient's role in their care. This distinction is crucial for fostering a supportive patient-provider relationship built on trust and shared goals.
| Feature | Adherence | Compliance |
|---|---|---|
| Patient's Role | Active and collaborative; the patient voluntarily agrees to the treatment plan. | Passive; the patient is expected to obediently follow instructions without question. |
| Decision-Making | Shared decision-making between the patient and the healthcare provider. | The provider is the authority figure who issues instructions. |
| Psychological Aspect | Patient takes responsibility for their well-being, empowered by the treatment plan. | Implies obedience to authority, with no proactive or independent choice by the patient. |
| Non-following Behavior | Patient is considered 'non-adherent' and the reasons are explored collaboratively. | Patient may be labeled as 'non-compliant,' implying disobedience or failure. |
Key Factors Influencing Adherence
Adherence is a complex and multifactorial issue, influenced by a wide range of factors organized into five dimensions according to the WHO framework. Addressing these specific barriers is key to developing effective interventions. These factors include patient-related issues like forgetfulness, beliefs about medication, and health literacy; therapy-related factors such as complex regimens and side effects; socioeconomic factors like treatment cost and social support; and healthcare system-related issues including communication with providers and access to care.
Methods for Measuring Treatment Adherence
Assessing adherence is crucial for monitoring treatment effectiveness, but there is no single "gold standard" method. Healthcare providers often use a combination of direct and indirect methods.
Indirect methods
Indirect methods are less intrusive and include self-reporting through diaries or questionnaires, pill counts, reviewing pharmacy refill records, and using electronic monitoring devices. While useful, these methods can be subject to inaccuracies due to recall bias, patients discarding pills, or devices not confirming ingestion.
Direct methods
Direct methods provide more objective data and include direct observation of the patient taking medication and measuring drug levels in bodily fluids (biochemical markers). These methods are generally more accurate but can be costly and less practical for long-term monitoring.
The Consequences of Poor Adherence
Poor adherence has severe consequences for both individual patients and the healthcare system, leading to treatment failure and significant economic burden. It can result in worsening health outcomes, increased morbidity and mortality, a higher risk of hospitalizations and emergency room visits, and a reduced quality of life. The financial impact is substantial, with estimates of the annual economic cost of non-adherence in the U.S. reaching hundreds of billions of dollars.
Strategies to Improve Adherence
Effective interventions for improving adherence often employ a combination of strategies tailored to the individual patient's needs. These strategies include providing clear patient education about their condition and treatment, fostering open communication with healthcare providers, simplifying complex medication regimens, utilizing medication reminder tools, addressing the cost of medication, and involving pharmacists and other members of the care team. The American Medical Association emphasizes that addressing potential non-adherence is a critical step in providing effective care.
Conclusion
Defining adherence to treatment involves a collaborative relationship where patients actively participate in and agree to a plan that may include medication, diet, or lifestyle changes. The shift from 'compliance' to 'adherence' reflects a modern, patient-centered approach that empowers individuals and builds trust with healthcare providers. Recognizing the various patient, therapy, socioeconomic, and healthcare system factors that influence adherence is crucial for addressing the issue effectively. Poor adherence carries significant health and financial consequences, emphasizing the importance of tailored, multifaceted interventions to support patients. By promoting better communication, patient education, and support tools, the healthcare system can improve adherence, leading to better clinical outcomes and a higher quality of life.
