title: Higher serum potassium level associated with late stage chronic kidney disease.
abstract: BACKGROUND
  The serum potassium (K+) level is kept in a narrow range to sustain normal physiology within the human body by the kidneys. The serum K+ level in different stages of chronic kidney disease (CKD) remains undefined.
  
  
  METHODS
  We conducted a cross-sectional study to observe the serum K+ level in patients without clinical manifestations of hyperkalemia in the late stages of CKD (stages 3-5). A total of 531 patients with late stage CKD were included and followed up for at least 1 year, from March 2006 to May 2007. The patients were sub-grouped by stages of CKD, which were determined by a "Modification of Diet in Renal Disease" equation estimating the glomerular filtration rate (eGFR). The serum creatinine, eGFR and K+ levels were recorded at least twice during the study. We analyzed the average K+ level in these late-stage CKD patients.
  
  
  RESULTS
  The average K+ level increased along with renal function deterioration in the late stages of CKD (stage 3: 4.36 ± 0.49; stage 4: 4.50 ± 0.55; stage 5: 4.69 ± 0.73 mEq/L, p < 0.05). Men and patients with diabetes mellitus, a low eGFR, and a low hemoglobin might have higher levels of serum K+. We also noticed that there was a linear increase in the standard deviation of the serum K+ level as renal function deteriorated. The use of angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers was not associated with hyperkalemia in our patients.
  
  
  CONCLUSIONS
  Our results reflected that the serum K+ level increased in correlation with the decline in the eGFR in the late stages of CKD. Also, male gender, diabetes mellitus, and anemia might be risk factors for higher K+ levels in CKD patients. The variation in the serum K+ level became wider as renal failure progressed.
authors: Department of Nephrology, Chang Gung Memorial Hospital at Keelung, Chang Gung University College of Medicine, Taoyuan, Taiwan.
authors: Ming-Fang
authors: MF
authors: Hsieh
authors: I-Wen
authors: IW
authors: Wu
authors: Chin-Chan
authors: CC
authors: Lee
authors: Shun-Yin
authors: SY
authors: Wang
authors: Mai-Szu
authors: MS
authors: Wu
mesh_terms: D000328:Adult; D000368:Aged; D057911:Angiotensin Receptor Antagonists / Q000494:pharmacology; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology; D002908:Chronic Disease; D003430:Cross-Sectional Studies; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007674:Kidney Diseases / Q000097:blood* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011188:Potassium / Q000097:blood*
chemical_list: D057911:Angiotensin Receptor Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors; D011188:Potassium