Abstract：ObjectiveTo evaluate the diagnostic ability of primary aldosteronism(PA) via the changes of plasma renin activity(PRA) with postural variation in hypertensive patients.MethodsThree hundred and seven patients had received the estimation of PRA,aldosterone level on basal sitting posture and after 2 hours on upright,sitting and supine posture,and collection of other biochemistry measurements.PA group was defined according to aldosterone/renin acrivity ≥554pmol/L·［μg/ (L·h)］-1 and plasma aldosterone concentration≥277pmol/L after saline infusion test,the rest were regarded as no-PA group.Related parameters were calculated to show the sensitivity and specificity,and so on.ResultsIn PA group,the levels of PRA upright,sitting,supine ［0.61μg/（L·h），0.62μg/（L·h），0.31μg/（L·h）］ were lower than those of noPA group［1.42μg/（L·h），1.18μg/（L·h），0.51μg/（L·h）］,and the differences were statistically significant (F=11.465,12.052,10.296；P=0.001).The Dvalue［0.24μg/(L·h)］ of PRA between PRA upright and PRA supine in PA group was lower than that ［0.78μg/（L·h）］ in no-PA group,and the difference was statistically significant (F=8.303,P=0.004).The sensitivity values of PRA upright <1.0μg/（L·h） or PRA uprightPRA supine<0.6μg/（L·h） to diagnose PA were 64% and 70%,respectively;the specificity values were 62% and 68%;the negative predictive values were 91% and 93%,respectively.Using PRA upright<1.0μg/（L·h） and PRA upright-PRA supine <0.6μg/（L·h） as diagnostic criterion of PA,the sensitivity and specificity values were 45% and 88%,respectively.ConclusionsThere is a low efficacy to use the changes of PRA via posture alteration as a diagnostic standard,but it′s brief and safe to provide some referenced information to doctors on the identification of PA.
