High salt intake is known to increase blood pressure (BP) and also to be associated with carotid-femoral pulse wave velocity (cf-PWV). However, recent data showed a sex-specific pattern in the salt-induced rise of BP. Thus, we aimed to investigate whether the association between salt intake and arterial stiffness also has a sex-specific pattern. A total of 7755 normotensive participants with a validated 12-h overnight urine collection in which daily salt intake was estimated were included. cf-PWV, as well as clinical and anthropometric parameters, was measured. Salt intake positively correlated with cf-PWV, in which the linear regression was steeper in women than in men (0.0199 ± 0.0045 vs 0.0326 ± 0.0052 m/s per gram of salt, P < .05). cf-PWV increases over the salt quartiles in men and women. However, after adjustment for confounders, the association remained significant only for men. In the path analysis, the direct path (men: 0.048 P < .001, women: 0.029 P = .028) was higher in men while that mediated by SBP (men: 0.020 P < .001, women: 0.034 P < .001) was higher in women. We clearly demonstrated that high salt intake has a direct and independent effect increasing arterial stiffness regardless of sex. Also, the association between salt intake and arterial stiffness is more dependent on BP in normotensive women than it is in normotensive men. These results highlight the need for a sex-specific approach in the evaluation of cardiovascular risk associated with dietary habits.
Keywords: arterial stiffness; blood pressure; mediation; salt intake; sex differences.
© 2019 Wiley Periodicals, Inc.