Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Observational Study
. 2019 Mar 7;14(3):330-340.
doi: 10.2215/CJN.07820618. Epub 2019 Feb 14.

Urinary Potassium Excretion and Progression of CKD

Hyung Woo Kim  1 , Jung Tak Park  1 , Tae-Hyun Yoo  1 , Joongyub Lee  2 , Wookyung Chung  3 , Kyu-Beck Lee  4 , Dong-Wan Chae  5 , Curie Ahn  5 , Shin-Wook Kang  1 , Kyu Hun Choi  1 , Seung Hyeok Han  1 ; KNOW-CKD Study Investigators
Affiliations
Observational Study

Urinary Potassium Excretion and Progression of CKD

Hyung Woo Kim et al. Clin J Am Soc Nephrol. .

Abstract

Background and objectives: Data on whether low or high urinary potassium excretion is associated with poor kidney outcome have been conflicting. The aim of this study was to clarify the association between urinary potassium excretion and CKD progression.

Design, setting, participants, & measurements: We investigated the relationship between lower urinary potassium excretion and CKD progression and compared three urinary potassium indices among 1821 patients from the Korean Cohort Study for Outcome in Patients with CKD. Urinary potassium excretion was determined using spot urinary potassium-to-creatinine ratio, spot urinary potassium concentration, and 24-hour urinary potassium excretion. Patients were categorized into four groups according to quartiles of each urinary potassium excretion metric. The study end point was a composite of a ≥50% decrease in eGFR from baseline values and ESKD.

Results: During 5326 person-years of follow-up, the primary outcome occurred in 392 (22%) patients. In a multivariable cause-specific hazard model, lower urinary potassium-to-creatinine ratio was associated with higher risk of CKD progression (adjusted hazard ratio, 1.47; 95% confidence interval, 1.01 to 2.12) comparing the lowest quartile with the highest quartile. Sensitivity analyses with other potassium metrics also showed consistent results in 855 patients who completed 24-hour urinary collections: adjusted hazard ratios comparing the lowest quartile with the highest quartile were 3.05 (95% confidence interval, 1.54 to 6.04) for 24-hour urinary potassium excretion, 1.95 (95% confidence interval, 1.05 to 3.62) for spot urinary potassium-to-creatinine ratio, and 3.79 (95% confidence interval, 1.51 to 9.51) for spot urinary potassium concentration.

Conclusions: Low urinary potassium excretion is associated with progression of CKD.

Keywords: Confidence Intervals; Disease Progression; Follow-Up Studies; Kidney Failure, Chronic; Potassium; Proportional Hazards Models; Renal Insufficiency, Chronic; Urinary potassium excretion; chronic kidney disease; creatinine; glomerular filtration rate; kidney.

PubMed Disclaimer

Figures

None
Graphical abstract
Figure 1.
Figure 1.
Cumulative incidence of CKD progression according to baseline spot urinary potassium-to-creatinine ratio. Adverse kidney events occurred more as urinary spot urinary potassium-to-creatinine ratio was lower (P<0.001 for the Gray test). Q, quartile.
Figure 2.
Figure 2.
The relationships between three urinary potassium metrics and CKD progression. Cubic spline analyses showed that there were inverse associations of spot urinary potassium-to-creatinine ratio (A), spot urinary potassium concentration (B), and 24-hour urinary potassium excretion (C) with CKD progression. All curves represent multivariable-adjusted hazard ratios. Hazard ratios were adjusted for age, sex, smoking status, body mass index, comorbid disease (diabetes and cardiovascular disease), mean arterial pressure, eGFR, C-reactive protein level, intact parathyroid hormone level, serum albumin level, serum calcium level, spot urinary Na-to-Cr ratio (24-hour urinary sodium excretion for 24-hour urinary potassium excretion), spot urinary protein-to-creatinine ratio (24-hour urinary protein for 24-hour urinary potassium excretion), LDL cholesterol level, and renin-angiotensin system blocker, statin, and diuretics usage. The histograms in A–C represent the frequency distribution of spot urinary potassium-to-creatinine ratio, spot urinary potassium, and 24-hour urinary potassium, respectively. Median value of each urinary potassium metric was set as a reference.
Figure 3.
Figure 3.
Subgroup associations of urinary potassium-to-creatinine ratio with CKD progression. The significant association between urinary potassium excretion and CKD progression was seen in most subgroups. Cause-specific hazard ratios (HRs; 95% confidence intervals [95% CIs]) per 1-SD lower spot urinary potassium-to-creatinine ratio (millimoles per gram) were on log scale. HRs were adjusted for age, sex, smoking status, body mass index, comorbid disease (diabetes and cardiovascular disease), mean arterial pressure, eGFR, high-sensitivity C-reactive protein level, intact parathyroid hormone level, serum albumin level, serum calcium level, spot urinary Na-to-Cr ratio, spot urinary protein-to-creatinine ratio, LDL cholesterol level, and renin-angiotensin system blocker, statin, and diuretics usage. UPCR, urinary protein-to-creatinine ratio.
See this image and copyright information in PMC

Comment in

References

    1. Holbrook JT, Patterson KY, Bodner JE, Douglas LW, Veillon C, Kelsay JL, Mertz W, Smith JC Jr.: Sodium and potassium intake and balance in adults consuming self-selected diets. Am J Clin Nutr 40: 786–793, 1984 - PubMed
    1. Mente A, O’Donnell MJ, Rangarajan S, McQueen MJ, Poirier P, Wielgosz A, Morrison H, Li W, Wang X, Di C, Mony P, Devanath A, Rosengren A, Oguz A, Zatonska K, Yusufali AH, Lopez-Jaramillo P, Avezum A, Ismail N, Lanas F, Puoane T, Diaz R, Kelishadi R, Iqbal R, Yusuf R, Chifamba J, Khatib R, Teo K, Yusuf S; PURE Investigators : Association of urinary sodium and potassium excretion with blood pressure. N Engl J Med 371: 601–611, 2014 - PubMed
    1. O’Donnell M, Mente A, Rangarajan S, McQueen MJ, Wang X, Liu L, Yan H, Lee SF, Mony P, Devanath A, Rosengren A, Lopez-Jaramillo P, Diaz R, Avezum A, Lanas F, Yusoff K, Iqbal R, Ilow R, Mohammadifard N, Gulec S, Yusufali AH, Kruger L, Yusuf R, Chifamba J, Kabali C, Dagenais G, Lear SA, Teo K, Yusuf S; PURE Investigators : Urinary sodium and potassium excretion, mortality, and cardiovascular events. N Engl J Med 371: 612–623, 2014 - PubMed
    1. O’Donnell MJ, Yusuf S, Mente A, Gao P, Mann JF, Teo K, McQueen M, Sleight P, Sharma AM, Dans A, Probstfield J, Schmieder RE: Urinary sodium and potassium excretion and risk of cardiovascular events. JAMA 306: 2229–2238, 2011 - PubMed
    1. Dunkler D, Dehghan M, Teo KK, Heinze G, Gao P, Kohl M, Clase CM, Mann JF, Yusuf S, Oberbauer R; ONTARGET Investigators : Diet and kidney disease in high-risk individuals with type 2 diabetes mellitus. JAMA Intern Med 173: 1682–1692, 2013 - PubMed

MeSH terms