Health Literacy, Medication Adherence, and Blood Pressure Level among Hypertensive Older Adults Treated at Primary Health Care Centers.

We conducted this study to explore the causal relationships between health literacy, individual characteristics, literacy, culture and society, cognitive ability, medication adherence, and the blood pressure levels of hypertensive older adults receiving health care services at Primary Health Care Centers in Sa Kaeo Province, Thailand. Six hundred hypertensive older adults had their blood pressure level recorded and were interviewed using questionnaires. Structural Equation Modeling (SEM) was used to determine the effect size, both direct and indirect, among factors. Almost half (48.7%) of studied subjects had inadequate health literacy, 98.3% had good medication adherence, and 80% had good blood pressure levels. The highest effect size on health literacy was literacy, followed by cognitive ability, and culture and society. Medication adherence was affected directly and indirectly by cognitive ability, literacy, and culture and society. Health literacy had not only a direct effect on medication adherence but was also the mediator. Finally, the highest effect size on blood pressure level was critical and communicative health literacy. These findings suggest that health literacy should be considered in the Health Literacy Program of the National Public Health Policy and Plan, Ministry of Public Health.