Key result
Low morning urine sodium-to-potassium ratio identifies high aldosterone in hypertensive men with ~98% specificity.
Why the study?
Patients with secondary hypertension due to hyperaldosteronism often remain undiagnosed in current clinical settings, necessitating a simple screening method.
Does the second morning urine sodium/potassium ratio accurately screen for hyperaldosteronism in hypertensive individuals not on antihypertensive medications?
Cross-Sectional (n=160)
No
Does the second morning urine sodium/potassium ratio accurately screen for hyperaldosteronism in hypertensive individuals not on antihypertensive medications?
A second morning urine sodium/potassium ratio <1.0 provides high specificity (97.9%) for detecting hyperaldosteronism in hypertensive men, offering a simple, low-cost screening method.
May support urine Na/K ratio as a specific screen for hyperaldosteronism in untreated hypertensive men; leaves open prospective validation.
Among individuals with hypertension, the prevalence of secondary hypertension has been reported to be ≈10%. More than half of individuals with secondary hypertension have associated hyperaldosteronism. However, given the current clinical environment, these patients often remain undiagnosed. We 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. We recruited hypertensive individuals aged 30-69 years old who were not taking any antihypertensive medications from among participants in health examinations. Urinary Na and K were measured using second morning urine samples, and the plasma aldosterone concentration (PAC) was also measured. We 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. Overall, 160 participants (108 men and 52 women) with a mean age of 54.3 years were eligible for this study. 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 <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 use of the urinary Na/K ratio may be appropriate as a method of screening for hyperaldosteronism in hypertensive men.
No takes yet. Share an insight, caveat, or question.
Segawa et al. (2021) conducted a cross-sectional in Hypertension (n=160). Second morning urine sodium/potassium ratio was evaluated on High plasma aldosterone concentration (≥90th percentile) in men (AUC 0.77, 95% CI 0.59-0.95). In hypertensive men, a second morning urine sodium/potassium ratio <1.0 predicted high plasma aldosterone concentration with an area under the curve of 0.77, 45.5% sensitivity, and 97.9% specificity.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: