Association Between Health Literacy and Prehypertension in South Korean Adults: Cross-Sectional Study Using the 2023 Korea National Health and Nutrition Examination Survey.

Low health literacy was associated with a significantly higher likelihood of prehypertension after multivariable adjustment.

• Adults with low health literacy had a 43% higher likelihood of prehypertension compared to those with high health literacy (odds ratio 1.43, 95% CI 1.07-1.91).
• The analysis used a multivariable survey-weighted logistic regression model adjusting for sociodemographic and health-related covariates.
• Data were drawn from the 2023 Korea National Health and Nutrition Examination Survey with a total analytic sample of N=1873 adults aged 19 years and older.

Prehypertension and low health literacy were both prevalent in the study sample.

• Of the 1873 participants, 319 (17.0%) had prehypertension.
• 1098 participants (58.6%) showed low health literacy.
• Prehypertension was defined as a systolic blood pressure of 130 to 139 mm Hg or a diastolic blood pressure of 80 to 89 mm Hg.
• Health literacy was measured using the Korean Health Literacy Index.

The protective impact of health literacy on prehypertension was not uniform but varied across demographic subgroups.

• Subgroup analyses revealed context-dependent variation in the association between health literacy and prehypertension.
• The authors identified three potential mechanisms: motivation for and dependency on health information (e.g., in women, middle-aged, lower education, and unemployed groups); synergy between health literacy and resources (e.g., in high-income, urban, married, and employer-insured groups); and preventive efficacy in low-risk populations.
• These patterns suggest that demographic context modulates how health literacy relates to prehypertension risk.

The study used a nationally representative cross-sectional design with a stratified, multistage clustered sampling methodology.

• Data were obtained from the 2023 Korea National Health and Nutrition Examination Survey.
• A stratified, multistage clustered sampling design was used to invite participants.
• Participants were adults aged 19 years and older who completed the Korean Health Literacy Index.
• Survey-weighted analytic methods were applied to account for the complex sampling design.

Health literacy may serve as a modifiable determinant and compensatory resource for cardiovascular risk prevention, particularly in populations with limited health care access.

• The authors frame health literacy as a 'modifiable determinant and compensatory resource for cardiovascular risk prevention.'
• The study highlights that targeted interventions addressing domain-specific health literacy deficits are needed to reduce the prehypertension burden.
• The study explicitly notes this research differs from prior work by focusing on prehypertension prevention rather than treatment adherence in diagnosed patients.
• The findings suggest health literacy may be especially important in populations with limited access to health care.