A scoping review of international literature on health literacy and polypharmacy.

BACKGROUND: Polypharmacy, the use of multiple medications, is linked to adverse outcomes. Shared decision making supports personalised care for patients with multiple medicines and long-term conditions, but relies on adequate health literacy. Health literacy - comprising functional, interactive, and critical domains - is often lower in people with chronic illness. This scoping review explores how health literacy is reported in the context of polypharmacy. AIM: The aim of this study was to examine how health literacy is conceptualised in literature where polypharmacy is present. METHOD: This was a systematic scoping review guided by Arksey and O'Malley's framework focused on standardised health literacy assessments in studies noting polypharmacy. The databases searched were Embase, MEDLINE, PsycINFO, Web of Science, and CINAHL. An author-developed tool extracted study characteristics, participant details, health literacy assessment type, and health literacy-polypharmacy relationships. RESULTS: The search yielded 711 citations; 17 were evaluated, 14 met inclusion. Thirteen studies used quantitative designs and one used mixed methods, across six countries. Health literacy assessments varied: seven functional, one communicative, and six critical. Fourteen assessed patients; two also included input from doctors and carers. Six studies directly linked polypharmacy to low health literacy. All reported low health literacy, which was associated with poorer health outcomes. CONCLUSION: Health literacy in the context of polypharmacy is underexplored. Evidence is limited globally, but existing studies consistently report low health literacy and related adverse outcomes. Further research is needed to clarify this relationship and inform interventions.