Abstract:

Objective To investigate the roles of plasma aldosterone level,renin activity and aldosterone/renin ratio（ARR） in different-time supine and standing positions on the diagnosis of primary aldosteronism（PA）. Methods A total of 103 patients with suspected PA were enrolled,which included 44 cases of PA group and 59 cases of non-PA group. Blood samples were taken for standing position 2 h,supine position 4 h and supine position 2 h,and plasma aldosterone level and renin activity were determined,and ARR was calculated. Receiver operating characteristic（ROC）curve was used to analyze the diagnostic value of ARR for PA. Results Between PA group and non-PA group,aldosterone levels,renin activities and ARR for standing position 2 h,supine position 4 h and supine position 2 h had statistical significance（P<0.01）. In PA group,aldosterone level,renin activity and ARR for standing position 2 h had statistical significance compared with those for supine position 4 h and supine position 2 h（P<0.05）. Within PA and non-PA groups,aldosterone level,renin activity and ARR for standing position 2 h,supine position 4 h and supine position 2 h had no statistical significance（P>0.05）. Aldosterone level,renin activity and ARR between supine position 4 h and supine position 2 h had no statistical significance（P>0.05）. ROC curve analysis results showed that the areas under curves（AUC） of ARR for standing position 2 h,supine position 4 h and supine position 2 h were 0.821,0.779 and 0.787,respectively. Conclusions ARR for standing position 2 h,supine position 4 h and supine position 2 h has certain accuracy in the diagnosis of PA. The test execution rate can be improved by supine position 2 h if the patients cannot lie for a long time.

Key words: Aldosterone/renin ratio, Supine position, Standing position, Primary aldosteronism