Special Issue: Adjustment to Chronic Illness Original Articles and Reviews
Supporting Adherence to Medicines for Long-Term Conditions A Perceptions and Practicalities Approach Based on an Extended Common-Sense Model Rob Horne, Vanessa Cooper, Vari Wileman, and Amy Chan Centre of Behavioral Medicine, Department of Practice and Policy, UCL School of Pharmacy, London, UK
Abstract: Pharmaceutical prescriptions are core to the treatment of most chronic illnesses, yet only half are taken as prescribed. Despite the high costs of nonadherence to individuals and society, effective adherence-promoting interventions are elusive. This is partly due to the sheer complicity of the issue. There are numerous determinants of adherence, both internal to the patient (intrinsic) and external (extrinsic, e.g., environmental or health system-related factors). Also, the relative importance of these determinants varies between individuals and even within the same individual over time and across treatments, presenting a challenge for intervention design. One complication is that interventions can target several levels: (1) patient (e.g., enhancing motivation and/or ability to adhere), (2) patient-provider interactions (e.g., improving communication and the prescribing process), and (3) the healthcare system (e.g., providing the opportunity to access medication through regulatory approval and co-payment schemes). Here, we focus on level 1: the patient. Although environmental factors are important, the effect of an intervention designed to change them will depend on how they impact on the individual. We describe the Perceptions and Practicalities Approach (PAPA), a pragmatic framework positing that adherence/nonadherence is essentially a produce of individual motivation and ability. Adherence interventions, targeted at any level, will therefore be more effective if tailored to address the perceptions and practicalities underpinning individual motivation and ability. We discuss how PAPA can be operationalized, including the application of theoretical models of illness and treatment representation (Necessity-Concerns Framework and Leventhal’s Common-Sense Model) to address salient adherence-related perceptions. Keywords: adherence, Perceptions and Practicalities Approach (PAPA), Necessity-Concerns Framework (NCF), interventions, Common-Sense Model (CSM)
Nonadherence to Medication in Chronic Illness: The Need for More Effective Interventions The prescription of a medicine is one of the most common interventions in developed health economies (Kantor, Rehm, Haas, Chan, & Giovannucci, 2015) and is essential to the treatment of most chronic illnesses (Simpson et al., 2006). However, treatment adherence rates are highly variable, ranging from 0% to over 100% (Nieuwlaat et al., 2014), depending on the condition, therapy, and methods used to measure adherence. The World Health Organization (WHO) estimates that, on average, only half of prescriptions for long-term conditions are taken as advised (Sabaté, 2003). If the prescription was appropriate, this may represent a lost opportunity for health gain and increased financial costs resulting from unnecessary escalations of treatment (DiMatteo, Giordani, Lepper, & Croghan, European Psychologist (2019), 24(1), 82–96 https://doi.org/10.1027/1016-9040/a000353
2002; Sabaté, 2003). The complex comorbidities that accompany many long-term conditions, with their associated polypharmacy and complicated medication regimes, further exacerbate the problem of nonadherence (Murray & Kroenke, 2001). Despite the costs of nonadherence to individuals and society, effective adherence-promoting interventions remain elusive. A series of systematic reviews have examined the efficacy of medication adherence interventions. These began with a review of 13 randomized controlled trials (RCTs) in 1996 (Haynes, McKibbon, & Kanani, 1996) and culminated in a recent Cochrane review which included 46,962 participants in 182 published RCTs across 24 conditions (Nieuwlaat et al., 2014). Although the number of RCTs investigating interventions has increased substantially in the last two decades, the findings have changed little. Each systematic review has concluded that while adherence can be improved, most interventions have limited effectiveness (Nieuwlaat et al., 2014). Ó 2019 Hogrefe Publishing
