Diagnostic value of aldosterone to renin ratio calculated by plasma renin activity or plasma renin concentration in primary aldosteronism: a meta-analysis

Evaluation of aldosterone to direct renin ratio, low renin and related Phenotypes in Afro-Colombian patients with apparent treatment resistant hypertension

Apparent resistant hypertension (aTRH) is a significant public health issue. Once low adherence to antihypertensive treatment has been ruled out and true resistant hypertension is diagnosed, aldosterone-direct-renin-ratio (ADRR) aids in the screening of an aldosterone-producing adenoma (APA) and primary aldosteronism (PA). Once PA and other secondary causes have been ruled out, the values of aldosterone and renin allow patients to be classified into phenotypes such as low renin hypertension (LRH), Liddle's-like (LLph), and primary hyperaldosteronism (PAph). These classifications could aid in the treatment decision-making process. However, optimal cut-off points for these classifications remain uncertain. This study aims to assess the prevalence of these phenotypes and the behavior of different cut-offs of the ADRR in an Afro-Colombian population with apparent resistant hypertension, as well to describe their sodium consumption. Afro-descendant individuals 18 years of age or older, diagnosed with resistant hypertension and attending to a primary care center in Colombia were recruited as volunteers. As part of the study, their plasma renin concentration (PRC) and plasma aldosterone concentration (PAC) were measured. The phenotypes were categorized into three groups based on multiple cut-off points from different authors: low renin and low aldosterone phenotype (LLph), low renin and high aldosterone phenotype (PAph), and high renin and high aldosterone phenotype, referred to as the renal phenotype (Rph). The prevalence of ADRR values exceeding the cut-off and phenotypes were calculated. A linear regression model was derived to assess the effect of sodium consumption with PAC, PRC and ADRR. A total of 88 patients with aTRH were included. Adherence to at least 3 antihypertensive medications was 62.5%. The median age was 56 years (IQR 48-60), 44% were female, and 20% had diabetes. The study found that the prevalence of ADRR values exceeding the cut-off ranged from 4.5 to 23%, while low-renin hypertension (LRH) varied from 15 to 74%, Rph was found in approximately 30 to 34% of patients, PAph in 30 to 51%, and the LLph in 15 to 41%, respectively, depending on the specific cut-off value by different authors. Notably, sodium consumption was associated with lower aldosterone (β - 0.15, 95% CI [- 0.27, - 0.03]) and renin concentrations (β - 0.75, 95% CI [- 1.5, - 0.02]), but ADRR showed no significant association with sodium consumption. There were no significant differences in prevalences between the groups taking < 3 vs ≥ 3 antihypertensive medications. Altered aldosterone-direct-renin-ratio, low renin hypertension, Liddle's-like, and primary hyperaldosteronism are prevalent phenotypes in patients within Afro-Colombian patients with apparent treatment-Resistant hypertension.

Comparison of plasma aldosterone measured by chemiluminescence immunoassay and liquid chromatography-tandem mass spectrometry in screening test for primary aldosteronism

Background

Whether chemiluminescence immunoassay (CLIA) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) for plasma aldosterone concentration (PAC) measurement can be used interchangeably in primary aldosteronism (PA) screening is still controversial. The purpose of this study was to compare CLIA to LC-MS/MS for PAC measurement in PA screening.

Methods

All participants underwent aldosterone-to-renin ratio (ARR) testing. PA was diagnosed by captopril challenge test or saline infusion test. PAC in screening test was measured with CLIA and LC-MS/MS. Plasma direct renin concentration in screening and confirmatory test was measured with CLIA. The concordance between CLIA and LC-MS/MS for PAC measurement in PA screening was analyzed.

Results

Twenty-one healthy volunteers, 61 patients with essential hypertension (EH) and 43 PA patients were enrolled. Median PAC by CLIA was 84.7 % higher than that by LC-MS/MS in screening test (P < 0.001). A positive correlation of PAC was observed between the two assays (Pearson r coefficient 0.770, P < 0.001). When ARR was used in differentiating PA from EH, there was no difference in the area under the receiver operating characteristic curve between CLIA and LC-MS/MS for PAC measurement (0.968 vs 0.950, P = 0.249).

Conclusion

CLIA and LC-MS/MS for PAC measurement exhibited high and comparable efficacy in PA screening. CLIA is a reliable and feasible alternative in PA screening test.

Aldosterone-to-renin ratio (ARR) as a screening tool for primary aldosteronism (PA)

The aldosterone-to-renin ratio (ARR) is the standard screening test for primary aldosteronism (PA). Because of the poor reproducibility of the ARR, repeat testing is recommended if the result is not compatible with the clinical condition. Various methods to measure renin are used in different hospitals in Taiwan, and the ARR cutoff values also differ among laboratories. The Task Force of Taiwan PA recommend using plasma renin activity (PRA) to calculate ARR instead of direct renin concentration (DRC) unless PRA is unavailable, because PRA is widely used in international guidelines and most studies.

Aldosterone and renin concentrations and blood pressure in young Indigenous and non-Indigenous adults in the Northern Territory: a cross-sectional study

OBJECTIVES

To evaluate aldosterone and renin levels and aldosterone-to-renin ratios (ARRs) in young Indigenous and non-Indigenous adults in the Northern Territory, and their association with blood pressure levels.

DESIGN

Cross-sectional study; single time point sub-study of two prospective birth cohort studies.

SETTING, PARTICIPANTS

Participants in the Aboriginal Birth Cohort (ABC) - born to Indigenous mothers at the Royal Darwin Hospital during 1987-1990 - and the Top End Cohort (TEC) - people born to non-Indigenous mothers in Darwin, recruited during 2007-2009 - aged 32-35 years at the time of this sub-study.

MAIN OUTCOME MEASURES

Plasma aldosterone and direct renin concentrations; ARRs (positive screening test result for primary aldosteronism defined as > 70 pmol/mU); systolic and diastolic blood pressure.

RESULTS

A total of 255 ABC (205 in remote, 50 in urban locations) and 76 TEC members participated. Median aldosterone concentration was similar for all three groups. The median renin concentration was 7.5 mU/L (interquartile range [IQR], 4.1-12.4 mU/L) in the TEC group, 12.4 mU/L (IQR, 5.1-19 mU/L) in the urban ABC group, and 29.3 mU/L (IQR, 15.0-52.9 mU/L) in the remote ABC group. The median ARR was 10 pmol/mU (IQR, 6-19 pmol/mU) in the remote ABC group, 28 pmol/mU (IQR, 16-70 pmol/mU) in the urban ABC group, and 43 pmol/mU (IQR, 26-74 pmol/mU) in the TEC group. Thirteen urban ABC participants (26%), 21 TEC participants (28%), and six people in the remote ABC group (3%) had ARR values above 70 pmol/mU. Adjusted for age and body mass index (BMI), mean systolic and diastolic blood pressure were lower for women than men in all participant groups; after adjusting for age, sex, and BMI, larger ARR was associated with higher systolic blood pressure in the TEC group but not the two ABC groups.

CONCLUSION

Screening test results for primary aldosteronism were positive for about one-quarter of urban Indigenous and non-Indigenous participants. A prospective study that includes confirmatory testing would more accurately assess the prevalence of primary aldosteronism among Indigenous Australians in the Northern Territory.