Sodium Intake and Its Relation to Coronary Calcium Score in Relatively Young Korean Adults

Background: There have been inconsistent findings regarding the effects of high sodium intake on coronary artery disease (CAD). This study therefore aimed to investigate the relationship between sodium intake and the coronary artery calcium score (CACS), reflecting coronary atherosclerosis. Method: Study participants were 89,337 Koreans in whom CACS and dietary sodium intake were measured during a health check-up. They were grouped according to quartile levels of dietary sodium intake. Multivariable logistic regression analysis was performed to evaluate the association between sodium intake quartiles and CACS > 0 (adjusted odds ratio [95% confidence interval]). Among participants with CACS > 0, linear regression analysis was conducted to assess whether a dose-response relationship exists between sodium intake and the severity of coronary artery calcification. Results: In all of the participants, an increase in sodium intake was modestly associated with CACS > 0 (first quartile: reference, second quartile: 1.06 [1.00-1.14], third quartile: 1.09 [1.01-1.16], and fourth quartile: 1.11 [1.03-1.20]). This association was observed only in men (first quartile: reference, second quartile: 1.07 [1.00-1.14], third quartile: 1.08 [1.01-1.16], and fourth quartile: 1.10 [1.02-1.19]). However, women did not show a significant association. Linear regression analysis also failed to show a significant association between quartile levels of sodium intake and CACS. Conclusion: There was a positive association between dietary sodium intake and a CACS > 0 in men. Our results suggest one possible mechanism linking high sodium intake to CAD.