Association Between Health Literacy and Medication Adherence in Hypertensive Patients

Abstract Background Nonadherence to antihypertensive therapy is a key barrier to effective blood pressure control. Health literacy (HL), as the ability to access, understand, and apply health information, may influence treatment adherence. This study aims to examine the association between HL and adherence to antihypertensive therapy. Methods A cross-sectional survey was conducted in October 2024 with 422 hypertensive adults attending an outpatient clinic, via face-to-face interviews. HL was assessed using the validated Turkish version of the HLS19-Q12 scale (Cronbach's alpha: 0,88), producing both percentage scores (0-100) and categorized levels. Medication adherence was assessed using the 12-item Hill-Bone Compliance to Blood Pressure Therapy Scale (Cronbach's alpha: 0,83), where lower scores indicate better adherence (range: 0-36). Mann-Whitney U and Kruskal-Wallis tests assessed group differences; Pearson correlation tested the association between HL and adherence. Results The mean adherence score was 7.83 (SD = 6.49). HL levels were: 22% inadequate, 32.7% problematic, 32.0% sufficient, 13.3% excellent. Better adherence was observed among patients living with others (mean: 7.45 vs. 9.33, p = 0.039), non-smokers (7.12 vs. 8.36, p = 0.037), those regularly measuring blood pressure at home (6.26 vs. 10.59, p < 0.001), who received disease education during their last visit (6.74 vs. 8.52, p = 0.001), and who knew the names of their medications (5.86 vs. 10.00, p < 0.001). HL was significantly associated with adherence: mean adherence scores were 11.65 (inadequate), 8.32 (problematic), 6.40 (sufficient), and 3.72 (excellent) (p < 0.001). Correlation was found between HL and adherence (r = -0.368, p < 0.001). Conclusions Health literacy is moderately associated with medication adherence. HL-sensitive communication and tailored education into routine care may enhance self-management in hypertensive patients and reduce complications associated with poor adherence. Key messages • Higher health literacy scores are associated with better adherence to antihypertensive therapy. • Health systems should integrate literacy-focused interventions to support chronic disease management.