Can supporting health literacy reduce medication-related harm in older adults?

More people than ever before are living into old age. The increased longevity is partly due to the increased use of medicines. Despite the potential benefits of medicines, they can still cause significant harm. Medication-related harm (MRH) may be from adverse drug reactions or harm from inappropriate drug use, for example, nonadherence or medication error. The European Commission estimated in 2008 that MRH contribute to at least 100,800 deaths in member states annually and costs society €79 billion.1 Older adults are most at risk due to their high exposure to medicines and age-related pharmacokinetic and pharmacodynamic changes. A recent systematic review found that 1 in 10 hospitalized older adults are admitted due to MRH, and approximately the same proportion experience MRH as an inpatient.2 Avoidable health service use due to MRH is substantial. A study in the Netherlands estimated the average cost of an avoidable MRH hospitalization in an older adult at €5500.3 Top-down interventions to reduce MRH and unplanned admissions, such as pharmacist-led medicines review, have shown limited effectiveness. There is a need to consider a bottom-up approach, exploring patient-centred modifiable determinants. Health literacy is one such determinant that is being explored in relation to MRH. A survey of eight countries in the European Union (EU) found that 30–60% of people are not health literate, with the older population representing a particularly high-risk group.4 A ‘mandate’ to enhance health literacy has been sent out to policy- makers in the 2016 World Health Organization (WHO) 9th Global Conference on Health Promotion. In this editorial we consider how health literacy can be conceptualized as a fundamental principle in reducing MRH in the older adult.