Differences of blood plasma renin activity, angiotensin Ⅱ and aldosterone levels in essential or secondary hypertension / 中华内科杂志

ABSTRACT

Objective To study on the difference of plasma renin activity ( PRA),angiotensin Ⅱ (Ang Ⅱ ),and aldosterone levels in patients with essential hypertension (EH) or primary aldosteronism (PA) or pheochromocytoma (PHEO),and to analyze the sensitivity and specificity on the diagnosis of PA among patients with hypertension with aldosterone/PRA ratio (ARR).Methods The plasma aldosterone,Ang Ⅱ and PRA concentrations in supine and upright positions were measured by radioimmunoassay from 413 patients including idiopathic hyperaldosteronism (IHA,n =111 ),aldosterone-producing adenoma (APA,n=l18),PHEO (n=98) and EH (n=86).ARR was calculated.Results Plasma aldosterone concentrations in both of supine and upright positions in PHEO group [ 374 (294,465 ) pmol/L and 629 (449,997) pmol/L] and PA group [471 (346,632) pmol/L and 673(499,825) pmol/L] were higher than those in EH group [ 277 (224,332) pmol/L and 427 (341,501 ) pmol/L ] (P ＜ 0.01 ).They were also higher in APA group [576 (416,731 ) pmol/L and 726 (554,906 )pmol/L ] than those in IHA group [399(313,504) pmol/L and 609(485,776)pmol/L ] (P ＜0.01).Ang Ⅱ levels in both positions were lower in PA group [43.2(26.4,74.4) ng/L and 60.1(38.5,103.6) ng/L] than in EH group [56.7 (43.3,78.9) ng/L and 84.3(61.3,108.4) ng/L] or PHEO group [54.3(29.9,101.5) ng/L and 102.8 (49.9,167.0) ng/L] (all P values ＜ 0.01 ),and there was no difference between IHA and APA group (P ＞ 0.05 ).The PRA level in both positions of each group were PHEO group [ 0.3 (0.2,1.0) μg ·L-1 · h-1 and 1.4(0.6,3.4) μg · L-1 · h-1] ＞EH group [0.2(0.1,0.4)μg · L-1 · h-1 and 0.6(0.4,1.0)μg· L-1 ·h-1] (P＜0.01) ＞PAgroup [0.1(0.1,0.1)μg· L-1 · h-1 and 0.2(0.1,0.3)μg·L-1 · h-1] (P＜0.01),and APA group [0.1(0.1,0.1)μg · L-1 · h-1 and0.1(0.1,0.3)μg · L-1 ·h - 1 ] ＜ IHA group [ 0.1 ( 0.1,0.2 ) μg · L - 1 · h - 1 and 0.2 (0.1,0.3 ) μg · L-1 · h - 1 ] ( supine P ＜0.01 ; upright P ＜ 0.05 ).APA was divided into 2 types with renin-Ang Ⅱ -responsive APA ( n =26) and unresponsive APA (n =92).The plasma aldosterone concentration was lower in supine position but higher in upright position in renin-Ang Ⅱ-responsive APA than in unresponsive APA patients.ARR in upright was higher in PA group ( P ＜ 0.01 ) but lower in PHEO group ( P ＜ 0.05 ) compared with EH.ARR was higher in APA than in IHA (P ＜0.01 ).The sensitivity and specificity of ARR as 40 (aldosterone unitng/dl;PRA unitμg · L-1 · h-1; its value should multiply 27.7 when transferred to pmol/L,simili) were 93％ and 76％,respectively.Conclusion The levels of PRA,Ang Ⅱ and aldosterone from patients with EH,PA and PHEO are significant different.ARR as 40 in upright position could be used for PA screening cutoff point.