LabMedica

Download Mobile App
Recent News Expo Clinical Chem. Molecular Diagnostics Hematology Immunology Microbiology Pathology Technology Industry Focus

Urinary Sodium/Potassium Ratio Screens for Hyperaldosteronism in Hypertensive Men

By LabMedica International staff writers
Posted on 08 Jun 2021
Print article
Image: Blood test for  plasma aldosterone concentration was used to screen For hyperaldosteronism in hypertensive men (Photo courtesy of  VisitHealth Ltd)
Image: Blood test for plasma aldosterone concentration was used to screen For hyperaldosteronism in hypertensive men (Photo courtesy of VisitHealth Ltd)
Among individuals with hypertension, the prevalence of secondary hypertension has been reported to be around 10%. More than half of individuals with secondary hypertension have associated hyperaldosteronism.

Hyperaldosteronism is a medical condition wherein too much aldosterone is produced by the adrenal glands, which can lead to lowered levels of potassium in the blood (hypokalemia) and increased hydrogen ion excretion (alkalosis).

A team of medical scientists led by those at Kyoto Prefectural University (Kyoto, Japan) hypothesized that the urinary sodium/potassium ratio (Na/K) could be used as a simple, low-cost method of screening for hyperaldosteronism among individuals with hypertension in primary care and health examination settings. They recruited hypertensive individuals aged 30-69 years old who were not taking any antihypertensive medications from among participants in health examinations. Overall, 160 participants (108 men and 52 women) with a mean age of 54.3 years were eligible for this study.

Urinary Sodium (Na) and potassium (K) were measured using second morning urine samples, and the plasma aldosterone concentration (PAC) was also measured. The assay kit used for the measurement of the PAC was the SPAC-S Aldosterone Kit (TFB, Inc. Tokyo, Japan). The team evaluated the association of the second morning urine Na/K ratio (SMU Na/K) with a high PAC, defined as ≥90th percentile (24.3 ng/dL), using receiver operating characteristic (ROC) curves.

The investigators reported that the area under the ROC curve for the relationship between SMU Na/K and high PAC was 0.77 (95% confidence interval [CI]: 0.59-0.95) in men and 0.64 (95% CI: 0.36-0.93) in women. In men, SMU Na/K values of less than 1.0 could detect hyperaldosteronism with a sensitivity of 45.5%, a specificity of 97.9%, a positive predictive value of 71.4%, and a negative predictive value of 94.1%.

The authors concluded that the use of the urinary Na/K ratio may be appropriate as a method of screening for hyperaldosteronism in hypertensive men. The urinary Na/K ratio in second morning urine was inversely associated with the PAC in hypertensive men but not in women. A low urinary Na/K ratio could be a surrogate marker for the detection of a high PAC in hypertensive men. The study was published on May 17, 2021 in the journal Hypertension Research.

Related Links:
Kyoto Prefectural University
TFB Inc


Platinum Member
COVID-19 Rapid Test
OSOM COVID-19 Antigen Rapid Test
Magnetic Bead Separation Modules
MAG and HEATMAG
Complement 3 (C3) Test
GPP-100 C3 Kit
New
Gold Member
TORCH Panel Rapid Test
Rapid TORCH Panel Test

Print article

Channels

Hematology

view channel
Image: The CAPILLARYS 3 DBS devices have received U.S. FDA 510(k) clearance (Photo courtesy of Sebia)

Next Generation Instrument Screens for Hemoglobin Disorders in Newborns

Hemoglobinopathies, the most widespread inherited conditions globally, affect about 7% of the population as carriers, with 2.7% of newborns being born with these conditions. The spectrum of clinical manifestations... Read more

Immunology

view channel
Image: The AI predictive model identifies the most potent cancer killing immune cells for use in immunotherapies (Photo courtesy of Shutterstock)

AI Predicts Tumor-Killing Cells with High Accuracy

Cellular immunotherapy involves extracting immune cells from a patient's tumor, potentially enhancing their cancer-fighting capabilities through engineering, and then expanding and reintroducing them into the body.... Read more

Microbiology

view channel
Image: The T-SPOT.TB test is now paired with the Auto-Pure 2400 liquid handling platform for accurate TB testing (Photo courtesy of Shutterstock)

Integrated Solution Ushers New Era of Automated Tuberculosis Testing

Tuberculosis (TB) is responsible for 1.3 million deaths every year, positioning it as one of the top killers globally due to a single infectious agent. In 2022, around 10.6 million people were diagnosed... Read more