Search

Context Current threshold values for primary aldosteronism (PA) diagnostic testing are based on measuring aldosterone (PAC) using immunoassays. Quantification of PAC by liquid chromatography-tandem mass spectrometry (LC-MS/MS) yields lower values. Objective To compare aldosterone measurement by radioimmunoassay (RIA) with LC-MS/MS and evaluate performances of proposed LC-MS/MS–specific cutoffs for PA screening and confirmatory testing. Patients and Intervention Forty-one patients underwent aldosterone/renin ratio (ARR) testing to screen for, and fludrocortisone suppression testing (FST) to confirm or exclude, PA. Renin (DRC) was measured by chemiluminescent immunoassay. Results Median serum PACLC-MS/MS was 27.8% lower (P < 0.05) than plasma PACRIA in 164 pairs of FST samples. A positive correlation (Spearman coefficient, 0.894, P < 0.01; Pearson r coefficient, 0.861, P < 0.01) was observed between the two assays. Thirty-seven patients showed consistent FST diagnoses (29 positive, 8 negative), whereas four showed inconsistent FSTs by the two assays. Good agreement (κ coefficient, 0.736; P < 0.01) was observed between the current FST diagnostic PACRIA cutoff of 165 pmol/L and the proposed PACLC-MS/MS cutoff of 133 pmol/L. Among 37 patients with consistent FST results, no differences were observed in sensitivity (89.7% vs 93.1%) or specificity (87.5% vs 87.5%) for PA screening between the current ARR cutoff of 70 pmol/mU (PACRIA/DRC) and the proposed cutoff of 55 pmol/mU (PACLC-MS/MS/DRC). Conclusions Adjustment of the current cutoffs for PA diagnostic testing is necessary if PAC is measured by LC-MS/MS. Our preliminary results suggest that the proposed LC-MS/MS cutoffs for ARR and FST perform as well as current RIA cutoffs.

Background: Plasma aldosterone/renin ratio (ARR) is the most popular screening test for primary aldosteronism (PA). Because both estrogen and progesterone (including in oral contraceptive agents) affect aldosterone and renin levels, we studied the effects of combined hormonal replacement therapy (HRT) on ARR; renin was measured as both direct renin concentration (DRC) and plasma renin activity (PRA). Methods: Fifteen normotensive, healthy postmenopausal women underwent measurement (seated, midmorning) of plasma aldosterone, DRC, PRA, electrolytes, and creatinine and urinary aldosterone, cortisol, electrolytes, and creatinine at baseline and after 2 weeks and 6 weeks of treatment with combined HRT (conjugated estrogens 0.625 mg and medroxyprogesterone 2.5 mg daily). Results: Combined HRT was associated with statistically significant increases in aldosterone [median (range): baseline, 150 (85 to 600); 2 weeks, 230 (129 to 790); 6 weeks, 434 (200 to 1200) pmol/L; P < 0.001 (Friedman test)] and PRA [2.3 (1.2 to 4.3), 3.8 (1.4 to 7.0), 5.1 (1.4 to 10.8) ng/mL/h, respectively; P < 0.001] but decreases in DRC [21 (10 to 31), 21 (10 to 39), and 14 (8.0 to 30) mU/L, respectively; P < 0.01], leading to increases in ARR calculated by DRC [7.8 (3.6 to 34.8), 11.4 (5.4 to 48.5), and 30.4 (10.5 to 90.2), respectively; P < 0.001]. The ARR calculated by DRC exceeded the cutoff value (70) in three patients after 6 weeks. There were no significant changes in ARR calculated by PRA [79 (26 to 184), 91 (23 to 166), and 88 (50 to 230), respectively; P = 0.282], plasma electrolytes and creatinine, or any urinary measurements. Conclusion: The combined oral HRT used in this study is capable of significantly increasing ARR with a risk of false-positive results during screening for PA but only if DRC (and not PRA) is used to calculate the ratio.

Background: The most popular screening test for primary aldosteronism is the plasma aldosterone/ renin ratio (ARR). Medications, dietary sodium, posture, and time of day all affect renin and aldosterone levels and can result in false-negative or false-positive ARRs if not controlled. Most antihypertensive medications affect the ARR and can interfere with interpretation of results. To our knowledge, no study has been undertaken to evaluate the effects of moxonidine on the ARR. Methods: Normotensive, nonmedicated male volunteers (n = 20) underwent measurement (seated, midmorning) of plasma aldosterone (by high-performance liquid chromatography-tandem mass spectrometry), direct renin concentration (DRC), plasma renin activity (PRA), cortisol, electrolytes and creatinine; and urinary aldosterone, cortisol, electrolytes and creatinine at baseline and after 1 week of moxonidine at 0.2 mg/d and a further 5 weeks at 0.4 mg/d. Results: Compared with baseline, despite the expected significant falls in both systolic and diastolic blood pressure, levels of plasma aldosterone [median, 134 (range, 90 to 535) pmol/L], DRC [20 (10 to 37) mU/L], PRA [2.2 (1.0-3.8) ng/mL/h], and ARR using either DRC [8.0 (4.4 to 14.4)] or PRA [73 (36 to 218)] were not significantly changed after either 1 [135 (98-550) pmol/L, 20 (11-35) mU/L, 2.0 (1.2-4.1) ng/mL/h, 8.8 (4.2 to 15.9), and 73 (32-194), respectively] or 6 weeks [130 (90-500) pmol/L, 22 (8 to 40) mU/L, 2.1 (1.0 to 3.2) ng/mL/h, 7.7 (4.3 to 22.4), and 84 (32 to 192), respectively] of moxonidine. There were no changes in any urinary measurements. Conclusion: Moxonidine was associated with no significant change in the ARR and may therefore be a good option for maintaining control of hypertension when screening for primary aldosteronism.

Context:In primary aldosteronism (PA), adrenal vein sampling (AVS) distinguishes unilateral and bilateral disease by comparison of aldosterone/cortisol (A/F) ratios. There is controversy about the criteria for interpretation, however, and in particular it is not clear whether contralateral suppression (CS) (defined as A/Fadrenal ≤ A/Fperipheral on the unaffected side) is important. We therefore performed a retrospective study to determine whether CS in surgically treated unilateral PA was associated with blood pressure (BP) and biochemical outcomes.Setting and Design:Patients who underwent unilateral adrenalectomy for PA after successful AVS were included if the lateralization index (A/Fdominant:A/Fnondominant) was ≥2. Cases were reviewed at 6 to 24 months follow-up for outcomes with respect to the presence and degree of CS.Results:Sixty-six of 80 patients had CS. Baseline characteristics were similar. At postoperative follow-up, those with CS had lower systolic BP (SBP) (128 mm Hg vs 144 mm Hg, P = .001), a greater proportion with cure or improvement of hypertension (96% vs 64%, P = .0034), a greater proportion with biochemical cure of PA on fludrocortisone suppression testing (43 of 49 [88%] vs 4 of 9 [44%], P = .002) and were taking a lower median number of antihypertensive medications (0 vs 1.5, P = .0032). In a multivariate model, the degree of CS and preoperative SBP were both significantly correlated with postoperative SBP, but the lateralization index, sex, and age were not.Conclusion:In this study, the presence of CS correlated with good BP and biochemical outcomes from surgery. This finding suggests that CS should be a factor in deciding whether to offer surgery for treatment of PA.

Measurement of quality of life (QOL) allows assessment of the impact of a disease or treatment from the patient's perspective, including need for social, emotional, or physical support. We are not aware of any published QOL assessment in patients with bilateral primary aldosteronism (BPA), before or after commencing medical treatment (MT) with spironolactone and/or amiloride.Using the internationally validated Medical Outcomes Study Short Form 36 General Health Survey (SF-36), QOL was assessed in 21 patients with BPA at baseline (time of diagnosis), and at 3 and 6 months after commencing MT. QOL scores at baseline were compared with published normative values for the Australian population. The results of the current study were compared with those from our previous study showing reduced QOL in patients with unilateral primary aldosteronism (UPA) with normalization by 3 months after unilateral laparoscopic adrenalectomy.Compared with the general population, patients with BPA showed significant reduction (P0.01) in four QOL domains--physical functioning, role limitations due to physical health problems, general health perceptions, and vitality. After 6 months (but not 3 months) of MT, statistically significant (P0.05) improvements were detected in all these domains of QOL. When compared with patients with UPA treated surgically, scores were significantly (P0.05) lower at 3 months for five domains (role limitations due to physical health, general health, role limitations due to emotional health, mental health, and vitality) but at 6 months for only one domain (role limitations due to emotional problems).Subnormal QOL scores were improved after 6 months of MT in 21 patients with BPA, but more slowly and to a lesser degree than surgical treatment had previously been shown to improve QOL scores in 22 patients with UPA.

The most popular screening test for primary aldosteronism is plasma aldosterone/renin ratio (ARR). Because both estrogen and progesterone affect aldosterone and renin levels, we studied effects of two contraceptives commonly used in our population, one oral and one subdermal, on ARR, measuring renin as both direct renin concentration (DRC) and plasma renin activity (PRA).Normotensive, healthy women underwent measurement (seated, midmorning) of plasma aldosterone, DRC, PRA, electrolytes, and creatinine and urinary aldosterone, cortisol, electrolytes, and creatinine at baseline (menses) and after either 1) 3 wk treatment with oral ethinylestradiol plus drospirenone (n = 17) or 2) 1 wk and 6 wk treatment with subdermal etonogestrel (n = 15), a third-generation progestin.Treatment with oral ethinylestradiol plus drospirenone was associated with significant increases in aldosterone [median (range) at baseline = 131 (85-590) pmol/liter; at 1 wk, 200 (130-784) pmol/liter; and at 3 wk, 412 (199-1010) pmol/liter (P0.001, Friedman test)] and PRA [2.1 (1.2-4.7), 3.6 (1.5-7.1), and 4.9 (1.5-10.8) ng/ml · h, P0.001] but decreases in DRC [22 (11-36), 21 (8.7-41), and 14 (8.5-39) mU/liter, P0.01] leading to increases in ARR calculated by DRC [6.6 (3.3-31.3), 10.9 (5.2-58.9), and 29.8 (5.1-88.5), P0.001]. There were no significant changes in ARR calculated by PRA, plasma electrolytes and creatinine, and all urinary measurements. In contrast, treatment with subdermal etonogestrel was associated with no significant changes in PRA, DRC, aldosterone, or ARR at either 1 or 6 wk.The combined oral contraceptive ethinylestradiol plus drospirenone is capable of significantly increasing ARR with risk of false-positive results during screening for primary aldosteronism, but only if DRC is used to calculate the ratio. Subdermal etonogestrel had no effect on ARR after 6 wk.