Medication non‐adherence: the hidden problem in clinical practice

Medication non-adherence was recognized over 2000 years ago when Hippocrates observed that patients did not always take the medicines recommended to them. Today, medication non-adherence remains a considerable and often hidden problem in clinical practice, with people typically taking only half of their prescribed medication. In this issue of the JEADV, Zschocke et al.1 explored adherence to psoriasis treatment. This is an important area of research with high relevance to clinical practice. We know that adherence can be problematic in people living with inflammatory skin conditions,2 and this is a missed opportunity for optimizing the effectiveness of available treatments. It can be difficult for patients to be honest about their medication usage, through fear of being labelled ‘a bad patient’. It is important that we take a non-judgemental approach and recognize non-adherence as the norm for at least some of the time. We all know how difficult it is to adhere to health behaviour recommendations, such as diet, alcohol and exercise; medication adherence is no different. Taking a ‘no-blame’ approach encourages honest and open discussions about medication use and is fundamental in helping to identify non-adherence and its causes. Just as we cannot ascertain a patient's medical diagnosis without performing diagnostic procedures or tests, we cannot discern which patients are (or are not) using their medication as prescribed. Adherence to medication involves complex combinations of decision-making and behaviours. This is particularly true in the context of dermatological conditions such as psoriasis. Even supposing the patient concurs with their clinician's choice of a therapy, they are then expected to make additional judgements such as ‘how much’ or ‘how often’ to use a topical treatment, or whether a recent infection is severe enough to justify omitting their next methotrexate dose. While adherence is sometimes labelled as intentional (patients decide to use less or more of their treatment than prescribed or stop treatment for a while) or unintentional (patients forget or lack capacity to use their medication), the reality is often more complicated. We need to know what level of adherence is ‘good enough’ for a particular therapy to advise patients about their degree of latitude. Finally, we need to develop accurate systems to determine the extent and types of non-adherent behaviours so that we can intervene as necessary. Improving medication adherence requires more than simply ‘giving advice’3 especially in the Internet age of readily accessible but potentially conflicting recommendations. So where should clinicians and researchers go from here? First, it is well established in other diseases such as asthma, cardiovascular disease and diabetes that patients’ beliefs about their illness and medication are key modifiable drivers of non-adherence. Patients’ experiences of medication can shape their expectations and vice versa.4 Patients who have concerns about the potential for adverse effects and perceive poor control of symptoms may underuse their psoriasis treatment to manage these concerns.5 Eliciting and addressing their perceived need for treatment and any concerns they may have about its usage could help support adherence6 Second, psychological distress can be very high in dermatology patients. This may reduce motivation and ability to manage their condition. Concerns about the nature or impact of dermatological treatments may be additional sources of distress; however, these issues are often missed or the distress is undertreated.7 Third, patients must also manage other real-life demands on their time and energy, such as relationships, work and additional comorbidities. It is important to encourage patients to discuss how medication use fits into their daily life and identify practical barriers they may face. Such discussions help identify potential solutions and develop good medication-taking routines. Longitudinal studies of treatment outcome in the ‘real world’ are increasingly common in dermatology. These provide the ideal platform to identify biomedical and psychological predictors of intentional and unintentional non-adherence. However, this is where the need for well-designed dermatology-specific measures is highlighted. The evidence supporting self-management interventions in dermatology is currently very limited.8 Understanding modifiable factors that influence non-adherence would pave the way to the development of tailored and targeted adherence interventions ultimately allowing patients to optimize the benefits from prescribed medicines. No external funding. RJT and CEMG are funded in part by the Medical Research Council, Grant MR/1011808/1. CEMG is a National Institute for Health Research Senior Investigator. CEMG has received research grant funding and/or honoraria from AbbVie, Almirall, Celgene, Janssen, Leo Pharma, Lilly, Novartis, Pfizer, Sun Pharmaceuticals and UCB Pharma. LC has received honoraria from AbbVie and Janssen and an unrestricted research grant from Pfizer. RJT has received an honorarium from Novartis.