OS 35-02 THE RELATION AMONG DIETARY SALT, ALDOSTERONE AND LEFT VENTRICULAR STRUCTURE IN PATIENT S WITH PRIMARY ALDOSTERONISM- A CASE-CONTROL STUDY.

OBJECTIVE: High dietary salt and high aldosterone levels may be deleterious to cardiac structure in patients with primary aldosteronism (PA) in samll studies. However the relation among them still unclear. We investigated the association among dietary sodium intake, aldosterone levela and cardiac structure in patients with PA and essential hypertension (EH).

DESIGN AND METHOD: This cross-sectional study enrolled 158 patients with confirmed PA and 158 patients with EH. We measured 24 hour urinary sodium (Una) and aldosterone (Ualdo) level while consuming usual diet and echocardiography parameters.

RESULTS: In analysis of left ventricular mass index, Una and Ualdo was not correlated with LVMI in EH patients. In patients with PA, Ualdo was positively correlated with left ventricular (LV) mean wall thickness (MWT; r = 0.189, p = 0.027) and left ventricular mass index (LVMI; r = 0.231, p = 0.007). The Una was not linearly associated with LV structural parameters in patients with PA. Multifactor ANOVA and post hoc analysis revealed that both higher and lower Una (1 and 3 tertile) were associated with higher LVMI compared with middle tertile Una (both p < 0.05) after adjusting clinical parameter (Figure 1, table 1). Furthermore, compare to middle tertile, PA patients with lowest Una have higher MWT but not cardiac dimention. In contrast, PA patients with highest Una have larger cardiac dimention but not MWT.

CONCLUSIONS: The middle tertile of Una is associated with lowest LVMI in patients with PA. The higher LVMI in other two groups may be due to different mechanisms.