ADDITIVE INTERACTION OF HIGH SODIUM INTAKE AND INCREASED SERUM TRIGLYCERIDE ON HYPERTENSION

Abstract Background and Aims Both high salt diet and abnormal lipid metabolism are critical risks of vascular endothelial dysfunction. This study investigated the interactive effects of increased sodium intake and elevated serum triglyceride (TG) on elevated blood pressure (BP). Method We conducted nation-wide, population-based interaction analysis using Kawasaki method for estimating 24-h urinary sodium excretion (e24hUNaEKawasaki) as a candidate indicator of dietary sodium intake. Eligible as cases were all native Koreans aged 20 years or older without significant medical illness. Results: A total of 16936 participants were divided into quintiles according to their e24hUNaEKawasaki results. Participants in the highest quintile were more obese and hypertensive and had increased white blood cell count, decreased hemoglobin, greater glycemic exposure, and poor lipid profiles as compared to lower quintiles. Linear regression showed that e24UNaEKawasaki was closely related with dietary sodium intake, systolic BP, diastolic BP, and TG. Multiple logistic regression, adjusted for dietary sodium intake and various conventional risk factors of hypertension, demonstrated that both e24UNaEKawasaki and TG were significant predictors of hypertension. Our interaction analysis revealed that high sodium intake had a bigger effect on the risk of hypertension in participants with elevated TG than those without (adjusted RERI = 0.022, 95% CI = 0.017-0.027; adjusted AP = 0.017, 95% CI = 0.006-0.028; adjusted SI = 1.010, 95% CI = 1.007-1.014). Conclusion Our findings indicate that the interaction of high salt diet and abnormal lipid metabolism may exert synergistic biologic effect on the increased arterial BP.