Clinical Value of Captopril Test for Primary Aldosteronism Diagnosis / 中国循环杂志

ABSTRACT

Objective: To evaluate the clinical value of Captopril test for diagnosing primary aldosteronism (PA) and to calculate the best cut-off point for PA diagnosis. Methods: We retrospectively analyzed 96 PA patients with conifrmed diagnosis by clinical situation, laboratory test and auxiliary examination in our hospital from 1994-06 to 2012-05, and meanwhile, studied 45 highly suspicious PA patients with final exclusion by confirmed diagnosis of primary hypertension (PH). All patients received the in-hospital Captopril test, the area under the curve of receiver operating characteristic (AUCROC) was applied to evaluate plasma aldosterone level and the ratio of aldosterone/renin after Captopril test and to obtain the best cut-off point with the corresponding sensitivity and speciifcity for PA diagnosis. Results: At 1h and 2h after Captopril test, AUCROC for plasma levels of aldosterone were 0.831 and 0.818, the ratios of aldosterone/rennin were 0.909 and 0.922 respectively. At 1h after Captopril test, the cut-off point of aldosterone level was 544.95 pmol/L and the diagnostic sensitivity was 70%, speciifcity was 90.7%; at 2h after Captopril test, the cut-off point of aldosterone level was 466.8 pmol/L and the diagnostic sensitivity was 69.8%, speciifcity was 70.5%. At 1h after Captopril test, the ratio of aldosterone/rennin was 34.6 [ng/dl μg/(ml·h)] with the sensitivity at 78.3% and speciifcity at 88.4%. At 2h after Captopril test, the maximum AUCROC for the ratio of aldosterone/rennin was obtained, when cut-off point of aldosterone level was 42.2[ng/dl μg/(ml·h)] , the diagnostic sensitivity was 76.7%, speciifcity was 95.3%. Conclusion: At 1h and 2h after Captopril test, plasma aldosterone level and the ratio of aldosterone/rennin had been valuable for PA diagnosis, the maximum diagnostic value could be obtained at 2h after Captopril test.