Presentation (CTI)

OBJECTIVES: Medication adherence is influenced by multiple patient-related factors, including health literacy and treatment involvement. While previous studies have demonstrated associations between health literacy and adherence, less is known about its relationship with specific reasons for low adherence. This study examined associations between health literacy, shared decision-making, medication adherence, and reasons for low adherence, and explored related patient experiences.
METHODS: A sequential explanatory mixed-methods design was used. Quantitative data were collected with the 13-item OsloMet Adherence-to-medication Survey, OMAS-13, and the Health Literacy Survey HLS19-Q12. Linear regression analyses examined associations between health literacy, medication adherence, and adherence-related challenges. Semi-structured interviews explored quantitative findings and were analysed using systematic text condensation.
RESULTS: Low medication adherence was identified in 50.8%, while 53.4% demonstrated low health literacy (n=191). Health literacy was significantly associated with medication adherence (p=0.012). Higher levels of perceived shared decision-making were associated with both better adherence (p=0.008) and higher health literacy (p<0.001). The most prominent reasons for low adherence were concerns about side effects or dependence, insufficient treatment effect, and treatment discontinuation when symptoms improved. Lower health literacy was significantly associated with challenges related to managing multiple medications (p=0.013) and perceived insufficient treatment effect (p=0.002). Qualitative findings (n=11) indicated that motivation for medication use was linked to understanding the treatment rationale. When information needs were not met by healthcare professionals, patients sought information independently and developed substantial knowledge about their condition and treatment. This facilitated involvement in treatment decisions, but also led some patients to modify medication use based on own assessment of benefits and risks.
CONCLUSIONS: Health literacy appears central to medication adherence, both directly and through its influence on shared decision-making and patients’ ability to manage medication-related challenges. Efforts to improve adherence should focus not only on patient behaviour, but also on strengthening health literacy and supporting patient involvement in treatment decisions.