Screening for primary aldosteronism in essential hypertension: diagnostic accuracy of the ratio of plasma aldosterone concentration to plasma renin activity.
Screening for primary aldosteronism in essential hypertension: diagnostic accuracy of the ratio of plasma aldosterone concentration to plasma renin activity.
复制标题
DOI：
10.1373/clinchem.2004.041780
复制
发表时间：
2005-02
影响因子：
9.3
通讯作者：
G. Schwartz;S. Turner
中科院分区：
文献类型：
--
作者：
G. Schwartz;S. Turner
背景：血浆醛固酮浓度与血浆肾素活性(PRA)的比值被认为是原发性醛固酮增多症的首选筛查指标。然而，关于其诊断的准确性以及抗高血压药物和膳食钠平衡对测试特征的影响仍存在不确定性。方法对118例既往诊断为原发性高血压的白人成人(男71例，女47例；平均年龄51(7)岁)进行PRA和醛固酮测定。在患者接受降压药物治疗时、停药2周后、饮食钠负荷4天后和急性速尿利尿后进行测量。我们在膳食钠负荷的第4天测定24小时尿醛固酮排泄量和肾素活性，以确定原发性醛固酮增多症的诊断。ROC曲线被构建为在每种临床条件下测量的比率，并确定了接受或停止抗高血压药物治疗的个体的似然比。结果15例患者[13%，95%可信区间(CI)，7-20%]符合原发性醛固酮增多症的参考标准。ROC曲线下的平均(SD)面积在不同测量条件下无显著差异[范围为0.80(0.10)至0.85(0.04)；P=0.72]。当测量是否接受降压药物治疗时，该比率的最佳临界点的95%的顺式曲线重叠。治疗前后敏感度积分估计分别为73%(95%CI，50-96%)和87%(70-100%)，特异度分别为74%(65-83%)和75%(66-84%)。在任何一种情况下，比率的增加都与测试后的赔率比测试前的赔率增加2.4到13倍相关。结论：在筛选原发性醛固酮增多症时，醛固酮/PRA比值只提供了较好的诊断准确性，但伴随的降压药物治疗或饮食钠平衡的急性变化不会对检测准确性产生不利影响。报告与醛固酮：PRA比值的取值范围相关的似然比，而不是使用单一的“最佳”切割点，可能会增强测试的有用性。
BACKGROUND The ratio of plasma aldosterone concentration to plasma renin activity (PRA) is considered the screening test of choice for primary aldosteronism. Uncertainty exists, however, regarding its diagnostic accuracy and the effects of antihypertensive drugs and dietary sodium balance on test characteristics. METHODS We measured PRA and aldosterone in 118 white adults [71 men and 47 women; mean (SD) age, 51 (7) years] with previously diagnosed essential hypertension. Measurements were made while individuals were on antihypertensive drug therapy, after a 2-week drug-free period, after 4 days of dietary sodium loading, and after acute furosemide diuresis. We measured 24-h urine aldosterone excretion and PRA on the 4th day of dietary sodium loading to establish the diagnosis of primary aldosteronism. ROC curves were constructed for ratios measured under each clinical condition, and likelihood ratios were determined for individuals on or off antihypertensive drug therapy. RESULTS Fifteen patients [13%; 95% confidence interval (CI), 7-20%] met the reference standard for primary aldosteronism. The mean (SD) areas under the ROC curves did not differ significantly across conditions of measurement [range, 0.80 (0.10) to 0.85 (0.04); P = 0.72]. When measured on and off antihypertensive drug therapy, the 95% CIs for the optimum cutpoint for the ratio overlapped. Point estimates of sensitivity on and off therapy were 73% (95% CI, 50-96%) and 87% (70-100%), respectively, and specificities were 74% (65-83%) and 75% (66-84%). Under either condition, increased ratios were associated with 2.4- to 13-fold increases of posttest odds above pretest odds. CONCLUSIONS The aldosterone:PRA ratio provides only fair diagnostic accuracy in screening for primary aldosteronism, but concomitant antihypertensive drug therapy or acute variation in dietary sodium balance does not adversely affect test accuracy. Reporting of likelihood ratios associated with ranges of values of the aldosterone:PRA ratio, rather than use of a single "optimum" cutpoint, may enhance the usefulness of the test.