Association Between Health Literacy and Medication Adherence Among Hispanics with Hypertension

Poor adherence to prescribed antihypertensive medication is a major contributor to disparities in effective blood pressure control among Hispanics. The purpose of this study was to investigate the association between health literacy level and adherence to antihypertensive medications among Hispanic adults, who self-reported hypertension, controlling for potential covariates of adherence and/or health literacy.

We conducted a cross-sectional survey of 1355 Hispanic adults, primarily Dominicans, who self-reported hypertension. Antihypertensive medication adherence and health literacy were evaluated along with covariates, including sociodemographic characteristics, depression, anxiety, and sleep disturbance. Linear regression models were created for health literacy, each covariate, and adherence. Factors found to be significantly associated with adherence in the individual regression models at a p value of < 0.20 were included in a hierarchical multiple linear regression model.

Overall, the majority of participants had low adherence levels to antihypertensive medications (88.4%; n = 1026) and inadequate health literacy (84.9%; n = 1151). When controlling for age, sex, birth country, education level, recruitment location, depression, anxiety, and sleep disturbance, having adequate as compared to inadequate health literacy was associated with a higher adherence score (b = 0.378, p = 0.043). The full model explained 13.6% of the variance in medication adherence (p value < 0.001), but the unique contribution of health literacy to the model was minimal (R² change = 0.003).

Tailored interventions considering health literacy are needed to support medication adherence in order to improve hypertension outcomes of Hispanics. Additional studies are needed to identify and prioritize factors in the development of targeted and effective adherence interventions for Hispanics with hypertension.