联合应用血钾血钠和尿钾尿钠的综合指数在原发性醛固酮增多症筛查中的作用

目的 评估联合应用血钾血钠和尿钾尿钠的综合指数(SUSPUP指数和SUSPPUP指数)在原发性醛固酮增多症(PA)筛杳中的作用.方法 对39例PA患者、296例原发性高血压患者及158名健康者进行立位1 h醛固酮浓度(PAC)及血浆肾素活性(PRA)、血钾、血钠、24 h尿钾和24 h尿钠的检测,计算出血钠/血钾、SUSPUP指数(血钠与尿钠的比值除以血钾与尿钾的比值)、SUSPPUP指数(血钠与尿钠的比值除以血钾平方与尿钾的比值)和PAC/PRA比值(Aaa),比较3组人群中以上指标的差异.构建和比较血钠/血钾、SUSPUP、SUSPPUP、PAC和ARR对诊断PA的ROC曲线.结果 (1)原发性高血压患者血钾和尿钠水平均低于健康者,而血钠水平则高于健康者.PA患者(3.3±0.6)mmol/L]较健康者(4.14±0.39)mmol/L]和原发性高血压患者(3.9±0.5)mmol/L]具有更低水平的血钾;与原发性高血压患者和健康者比较,PA患者具有更高水平的血钠(141.7±2.7)mmol/L比(140.2±2.3)mmol/L比(139.6 ±2.1)mmol/L]和尿钾(74 ±41)mmol/24 h比(36±17)mmol/24 h比(36±16)mmol/24 h]以及更高水平的SUSPUP(在PA、原发性高血压患者、健康者分别为27±13、12±9、9±4)和SUSPPUP指数(分别为9.0±6.4、3.3±2.8、2.1±1.1)mmol/L.(2)SUSPUP、SUSPPUP曲线下面积分别为0.824和0.840,与PAC相当(0.875),但低于ARR(0.991).SUSPUP的最佳切点为14.44,敏感性和特异性分别达到81.58%和75.56%;SUSPPUP的最佳切点为4.08,敏感性和特异性分别达到81.58%和80.00%.结论 SUSPUP和SUSPPUP也可以作为PA筛查的辅助指标,诊断效率达80%以上.

New index of using serum sodium and potassium and urine sodium and potassium jointly in screening primary aldosteronism in hypertensive patients

Objective Although the aldosterone-to-renin ratio (ARR) is valuable in the screening for primary aldosteronism ( PA) . However, the hormonal determinations are both time-consuming and expensive. So we tried to use new indexes of serum sodium to urinary sodium to serum potassium to urinary potassium (SUSPUP) and serum sodium to urinary sodium to (serum potassium)~2 to urinary potassium (SUSPPUP) in screening of PA. Methods The present study included 39 patients with PA, 296 patients with essential hypertension and 158 normotensitive subjects. Serum potassium and sodium, urine potassium and sodium were measured by ion-selective electrodes. In addition, serum aldosterone concentration and plasma rennin activity after staying upright for one hour were measured by radioimmunoassay. The serum potassium and sodium, urine potassium and sodium in these groups were evaluated in the screening of SUSPPUP for differentiating PA from hypertensive patients. Results (1) Compared with healthy volunteers, the essential hypertension patients had lower levels of both serum potassium and urine sodium, higher levels of serum sodium. Compared with healthy volunteers and primary hypertension patients, the PA patients had the lowest serum potassium and highest serum sodium, urine potassium resulting in the highest SUSPUP and SUSPPUP ratio. (2) The AUCs of SUSPUP and SUSPPUP were 0. 824 and 0. 840 respectively according to the ROC curve. The optimal cutoffs of SUSPUP and SUSPPUP were 14.44 and 4.08 respectively. Conclusion The SUSPUP and SUSPPUP ratios are rapid and inexpensive indices to assess the extent of mineralocorticoid excess. Therefore they may be employed to screen PA in hypertensive patients.