Medicines adherence in respiratory disease

Adherence is the term currently used to describe a patient following prescribed or suggested treatment regimens; in other words the degree to which a patient correctly follows medical advice (Bell et al, 2007). Adherence was previously, and sometimes concomitantly, known as compliance and concordance, however these terms are not synonymous (Bell et al, 2007). Concordance does not refer to a patient's medicine-taking behaviour, but instead to the nature of the interaction between clinician and patient (Bell et al, 2007).

Adherence is regarded as a major problem in all pharmacological interventions, with approximately half of all patients with chronic diseases not adhering to their medical regimens, so is not specific to respiratory diseases (Jungst, 2019).

Commonly, adherence refers to medication or drug compliance, but it also applies to interventions, such as the use of medical devices, self-directed exercise programmes, self-care, self-management, and therapy sessions such as pulmonary rehabilitation. It is known that both the person receiving the advice or prescription and the healthcare provider affect adherence, and it is said that a positive physician–patient relationship is the single most important factor in improving adherence; this finding has been consistent over time (World Health Organization (WHO), 2003; Mathes et al, 2014). The cost of prescription medication may also play a major role in adherence to therapies, although in 2016, 89.4% of prescriptions dispensed in England were free of charge so it is not the whole answer (National Institute of Health and Care Excellence (NICE), 2009; NHS Digital, 2016).