Association between household income and pulse pressure: data from the Korean National Health and Nutrition Examination Survey.

Purpose: There has been limited evidence for the association between socioeconomic status (SES) and arterial stiffness. This study was performed to investigate the association between household income and brachial pulse pressure (PP) in the general Korean population.

Materials and methods: This study was based on data acquired in the 2018 Korea National Health and Nutrition Examination Survey (2018 KNHANES). A total of 13004 subjects at the age of 20 years or older analysed. The information on monthly household income was obtained through the questionnaire, and was stratified into 5 groups for each quintile. Brachial blood pressure (BP) was measured 3 times, and the average of the second and third measured BPs were used. PP was calculated as the difference between systolic and diastolic BPs.

Results: A lower household income was associated with a higher prevalence of cardiovascular risk factors. As household income increased, PP decreased proportionally (p < .001). In multiple linear regression analysis, household income (per quintile) was independently associated with PP even after controlling for potential confounders (β = -.125, p < .001). Multiple binary logistic regression analysis showed that the increased household income level was significantly associated lower probability having higher PP (≥ 43.5 mmHg) even after controlling for multiple covariates (the lowest vs. the highest household income; odds ratio, 0.48; 95% confidence interval, .41-.55; p < .001).

Conclusion: Low household income was associated with higher PP. This provides additional evidence for the association between low SES and high arterial stiffness.