Knowledge, attitudes, and practices regarding dietary salt intake and its relationship with blood pressure in Vietnamese adults

Objectives This study aimed to assess knowledge, attitudes, and practices (KAP) related to dietary salt intake and to investigate the association between KAP and blood pressure among adults in Vietnam. Methods A cross-sectional study was conducted involving 2100 participants selected through a multistage random sampling method. Data were collected through face-to-face interviews using a structured questionnaire and anthropometric measurements. Multivariable logistic regression models were employed to identify factors associated with KAP, while multivariable linear regression models were used to examine the relationship between KAP levels and blood pressure. Results Among the 2100 participants, 24.9% demonstrated good knowledge, 32.3% exhibited positive attitudes, and 6.5% reported good practices regarding dietary salt intake. Only 11.1% of participants had good overall KAP. Participants with good knowledge had systolic blood pressure that was 1.80 mmHg lower than those with poor knowledge (95% CI: −3.15 to −0.45; p = 0.009). Similarly, participants with good practices had diastolic blood pressure that was 1.83 mmHg lower than those with poor practices (95% CI: −3.40 to −0.26; p = 0.023). Furthermore, participants with good overall KAP had lower systolic (−2.78 mmHg; 95% CI: −4.00 to −1.57; p < 0.001) and diastolic blood pressure (−2.27 mmHg; 95% CI: −4.07 to −0.47; p = 0.013) compared with those with poor overall KAP. Conclusions This study underscores the importance of improving knowledge and practices regarding dietary salt intake to enhance blood pressure control. Public health interventions promoting awareness and healthy behaviors may play a critical role in reducing hypertension.