Association between Health Literacy and Medication Adherence among Hypertensive Adults

Less than half of US adults with hypertension have their blood pressure controlled. This study examines health literacy and medication adherence among adults with hypertension in a primary care setting (n=196). Medication adherence was measured using the Hypertension Self-Care Activity Level Effects (H-SCALE), and health literacy was assessed using the Newest Vital Sign (NVS). Average age of the sample was 55.7 years, 67.2% were women, and 77.1% were Black. Within the sample, 51.9% were adherent to anti-hypertension medications, 51.8% had limited health literacy, 19.4% had moderate and 28.8 % had good health literacy. Logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) of the association between increasing levels of health literacy and medication adherence. In unadjusted analyses, patients with moderate health literacy had increased odds of medication adherence (OR=1.17; 95%CI=0.52-2.65), and those with good health literacy had reduced odds of being adherent to medications (OR=0.95; 95% CI=0.47-1.91) as compared to those with low health literacy. After adjusting for confounders, patients with moderate health literacy had 30% greater odds (OR=1.3; 95% CI=0.52-3.22), and those with good health literacy had 26% reduced odds of being adherent to medications (OR= 0.74; 95%CI= 0.31-1.77) as compared to those with low health literacy. Preliminary results suggest a curvilinear association between increasing health literacy and medication adherence. Adults with good health literacy may focus on other self-care activities, such as eating a low-salt diet, to manage blood pressure. Data collection is ongoing. Additional analyses will examine other hypertension self-care behaviors.