The impact of health literacy on adherence to isometric exercise and its effect on blood pressure in hypertensive patients

Background: Hypertension is a major global health problem and a leading cause of cardiovascular disease. Objective: This study aimed to analyze the influence of health literacy on adherence to isometric exercise and its effects on blood pressure reduction among patients with hypertension in Kolaka. Methods: A quasi-experimental study with a pretest–posttest control group design. Sixty respondents diagnosed with hypertension were randomly selected using simple random sampling and divided into two groups: 30 with higher health literacy and 30 with lower health literacy, as measured by the Health Literacy Questionnaire (HLQ). Blood pressure was measured before and after the intervention using a standardized digital sphygmomanometer. Data were analyzed using paired t-tests and ANCOVA with a significance level of p < 0.05, and Cohen’s d was calculated to determine the magnitude of the intervention effect. Results: The intervention group experienced a significant decrease in systolic blood pressure from 152.1 ± 9.0 to 141.3 ± 7.5 mmHg and in diastolic pressure from 95.2 ± 6.5 to 87.1 ± 5.8 mmHg (both p < 0.001; large effect sizes). In contrast, the control group showed no significant changes in either systolic or diastolic pressure (p > 0.05). ANCOVA revealed that health literacy significantly influenced reductions in both systolic (p = 0.014) and diastolic (p = 0.017) blood pressure, with a significant interaction between literacy level and exercise adherence (p < 0.05). Conclusion: Health literacy plays a crucial role in enhancing the effectiveness of isometric exercise in lowering blood pressure among hypertensive patients. Patients with higher literacy demonstrated greater adherence and achieved better blood pressure control.