Abstract:

Objective To investigate the role of plasma aldosterone to direct renin ratio（ADRR） in the diagnosis of primary aldosteronism（PA） and its optimal cut-off value. Methods A total of 222 hypertension patients were enrolled,and there were 33 cases of PA. Plasma aldosterone and renin were determined by chemiluminescence immunoassay. ADRR was calculated. Using receiver operating characteristic（ROC） curve,the role and cut-off value of ADRR for the diagnosis of PA were evaluated. Results The proportion of PA in hypertension patients was 14.86%（33/222）. Plasma renin levels at both supine and upright positions in PA group were lower than those in hypertension group（P<0.05）. ADRR in PA group was higher than that in hypertension group（P<0.05）. ROC curve analysis showed that the areas under curves（AUC） of ADRR were 0.906（supine position）and 0.908（upright position）. The optimal cut-off value of ADRR at supine position was 31.32. The sensitivity was 96.97%,and the specificity was 73.54%. However,the optimal cut-off value of ADRR at upright position was 27.57,the sensitivity was 81.82%,and the specificity was 86.77%. Conclusions Plasma ADRR is an effective index for PA screening,and the cut-off value 25 is optimal for screening ADRR at upright position.

Key words: Aldosterone, Renin, Aldosterone to direct renin ratio, Chemiluminescence immunoassay, Primary aldosteronism, Hypertension