Medication adherence—Everybody's problem but nobody's responsibility?

Medication nonadherence has become somewhat of an adage—starting with Hippocrates commonly used quote by adherence researchers: ‘Keep a watch … on the faults of the patients, which often make them lie about the taking of things prescribed’. Many publications focused on adherence refer to the statistic where approximately 50% of medicines prescribed to people with long-term conditions are not taken as recommended. This number originated in a Cochrane review published in 2002¹ and reached a global audience in the 2003 World Health Organization ‘Adherence to Long-Term Therapies: Evidence for Action’.² Whilst these documents are well overdue for updates, the statistic they promote is hardly groundbreaking anymore and has almost become accepted in practice and research as the ‘norm’. Despite decades of referring to the same statistic and millions of dollars of funding dedicated to research to investigate nonadherence, there has been little shift in the size and nature of the problem.

It is therefore time to ask ourselves—as clinicians, researchers and policymakers—whether we are becoming complacent in accepting that nonadherence is a public health problem that is here to stay. Medication adherence seems to be a problem that affects everybody—regardless of age, ethnicity, gender or health, yet nobody's responsibility to address. Is adherence simply a health problem that cannot be solved or have the key actors, such as health professionals and policymakers, become complacent?

The recent paper ‘Pan-European survey on medication adherence management by healthcare professionals’ by Kamusheva and colleagues³ as part of the European Cooperation in Science and Technology (COST) project ENABLE (European Network to Advance Best Practices and Technology on Medication AdherencE) comes at a timely moment as the adherence field begins to show signs of clinical inertia. The study provides insights into the practice of health professionals in relation to medication adherence across 40 European countries in a range of health professionals. The findings outline a sobering outlook on the current landscape of medication adherence practice. The survey data show that there is a risk that medication adherence is being de-prioritized in healthcare delivery despite being a critical determinant of variability in medication response and a central driver of good health outcomes.

Of the 2875 health professionals who participated, the most used method for monitoring medication adherence was by far ‘asking the patient’ (86.4% of respondents). Checking dispensing history or prescriptions was only performed by just over half of respondents (56.8%) despite the relatively easy accessibility to health records to health professionals. This is concerning and surprising as other aspects of clinical decision-making, such as the diagnosis of a health condition or medication administration, always involve checking of clinical records and careful establishment of case history.⁴ It would be considered a poor clinical practice if a physician made a clinical diagnosis by simply ‘asking the patient’ about symptoms without checking their clinical notes or if a nurse administered a medication without checking for allergies. This should be no different for the monitoring of medication adherence—yet why is the use of dispensing or prescribing records so low when it comes to medication adherence monitoring?

Whilst it is critical that the patient is involved as an information source for medication adherence monitoring, it is well-documented that patient self-report carries a large degree of bias and frequently overestimates adherence.⁵ We propose that it is better to make the most of the patient consultation time and use evidence-based validated questionnaires to elicit adherence instead rather than relying on an unstructured discussion with the patient. Less than 6% of the study respondents reported by Kamusheva and colleagues selected ‘validated questionnaires’ as their response option when asked which method they used for monitoring medication adherence, and this was mostly in Western European countries. There are clearly a wide range of validated adherence measurement tools that exist,^{6, 7} but they are being underutilized. This represents a significant research implementation gap for adopting validated adherence monitoring tools and an easy, practical opportunity to improve practice without necessitating major changes in practice or adoption of sophisticated or expensive tools whilst ensuring quality of adherence measurement.⁸

The lack of prioritization of medication adherence as a necessary clinical task was another notable finding from the study. It is concerning that just over half of the health professionals (53.7%) surveyed stated that they would check adherence if treatment goals were not reached, and importantly 4.4% reported that they would be unconcerned about their patients' medication adherence even if their condition was worsening. This raises the risk that there is a significant degree of unnecessary dose and/or treatment escalation occurring in practice if health professionals are not routinely checking adherence even if treatment goals are not achieved in their patients. With the widespread use of expensive treatments as step-up therapy in patients who do not respond to first-line agents, such as the use of biologics in inflammatory diseases in patients who do not respond to oral agents, it would be an irresponsible use of the health dollar⁹ and clinically inappropriate to skip this critical step of checking adherence prior to treatment escalation. Addressing adherence issues prior to treatment change is also necessary as changing treatment itself could worsen adherence.

Confusion about role responsibility and lack of ownership for addressing nonadherence was another factor exacerbating inaction towards addressing nonadherence. Approximately 11% of both nurses and of pharmacists reported that assessing treatment outcome is not their role. The main reason cited for not improving adherence was because the health professional did not conceive of it as their professional task, or that the task is the responsibility of other health professionals. The key question then is who's responsibility is it?

Professional responsibility for medicines management, which includes adherence, would suggest that pharmacists should be the health professional who is best placed to identify and address nonadherence.¹⁰ Yet from the Kamusheva et al. survey, pharmacists were the health profession who were least likely to monitor adherence with only 31.6% of pharmacist respondents stating they would assess adherence compared to 59.7% physicians and 53.9% of nurses. Pharmacists were also least likely to document nonadherence (52.0% compared with 70% physicians and 85% of nurses), and be involved in applying adherence enhancing interventions (57.7% vs. 81.1% physicians and 75.7% nurses) compared with other health professionals. Further qualitative work to follow-up these survey results would be useful to fully understand why this is the case. From the survey, the most commonly reported reason in pharmacists for not monitoring adherence was that there were no methods or data for monitoring, or no guidelines. The reasons for pharmacists not documenting adherence were a lack of knowledge on where to document or report; a lack of guidelines; or a lack of established good practices on documenting. This was also similar to the reasons reported by nurses and physicians, though the nurses and physicians were more likely to cite the lack of established practices as the most common reason for not recording nonadherence.

These findings serve as a wake-up call to the health sector to introspectively reflect on our day-to-day practice priorities. If the most cited reasons for not taking action towards nonadherence were a lack of knowledge, a lack of established practice and a lack of guidelines, then perhaps there needs to be a global standard for managing nonadherence that can be applied across cultures and regions. This would support a positive culture shift towards making adherence assessment and recording and adherence promotion the norm. The latest World Health Organization guideline on medication adherence was published in 2003,² over two decades ago. There is a need to revisit this and reinvigorate evidence-based practice towards improving medication adherence.

We propose three key recommendations as a call to action for all stakeholders involved in healthcare (Table 1) to improve and advance adherence. There is a clear need for a joined-up collaborative approach if we are serious about improving medication adherence and addressing this public health problem.

It is no longer sufficient to cite decades of literature and state that the adherence rate to medicines averages 50%. Deliberate and decisive action needs to be taken to raise the minimum standards of practice towards monitoring and improving adherence so that individuals, health professionals and policymakers alike can benefit from improved healthcare.

AHYC reports research grants from Health Research Council of New Zealand, Auckland Medical Research Foundation, Asthma UK, University of Auckland, Oakley Mental Health Foundation, Chorus Ltd, AstraZeneca, World Health Organisation, and Hong Kong University, outside the submitted work and all paid to her institution (the University of Auckland). AC previously held the Robert Irwin Postdoctoral Fellowship. AHYC also reports consultancy fees from AcademyeX and Spoonful of Sugar Ltd, travel support from AstraZeneca, and was previously on the Board of Asthma NZ. She is a member of Respiratory Effectiveness Group (REG), ESPACOMP research, policy and implementation committee, member of the Scientific Advisory Board for Asthma Respiratory Foundation NZ, and working group lead for the European Respiratory Society Clinical Research Collaboration “CONNECT.” DFBW is co-chair of the ESPACOMP research, policy and implementation committee and reports no other relevant conflicts of interest.