Clinica Chimica Acta-Serum potassium in renal impairment: At what concentration of estimated GFR does it rise?

摘要

Kidney disease is a well recognized cause of hyperkalaemia. Despite adaptive mechanisms that can maintain potassium at near normal concentrations, renal excretion of potassium is ultimately dependent on sufficient blood flow to the kidney for glomerular filtration and urinary tubular flow to the distal collecting duct. Hyperkalaemia requiring intervention is rarely a problem in chronic kidney disease until the glomerular filtration rate (GFR) falls below to 10-20 ml/min/1.73 m~2 [1,2]. Few studies have described the natural history of deteriorating GFR and potassium concentration in humans to examine at what concentration of GFR potassium begins to rise. Laboratory result data mining together with new mathematical modeling techniques such as locally weighted scatterplot smoothing (LOESS) now allows such relationships to be visualised. This study describes how serum potassium concentration changes with decreasing estimated GFR (eGFR) in 4 different patient populations.