Temporal Profile of Serum Potassium Concentration in Nondiabetic and Diabetic Outpatients on Chronic Dialysis

We analyzed routine serum potassium concentration measurements and conditions temporally associated with abnormalities in potassium concentration in outpatients on chronic hemodialysis (136 nondiabetics, 36 diabetics) and continuous ambulatory peritoneal dialysis (16 nondiabetics, 10 diabetics). The following potassium concentration frequencies were found: prehemodialysis, nondiabetics: normal 51.3%, severe hyperkalemia (greater than 6.0 mmol/l) 10%, severe hypokalemia (less than 3.0 mmol/l) 0.3%; diabetics: normal 57.8%, severe hyperkalemia 8.7%, severe hypokalemia 0.5%. Peritoneal dialysis, nondiabetics: normal 73.7%, severe hyperkalemia 0.6%, severe hypokalemia 4.9%; diabetics: normal 72.5%, severe hyperkalemia 0.9%, severe hypokalemia 2.9%. Normokalemia and severe hypokalemia were significantly (chi 2 test) more frequent in peritoneal dialysis than in prehemodialysis, whereas severe hyperkalemia was more frequent in prehemodialysis serum samples. No difference was found between nondiabetics and diabetics for either form of dialysis. 50% of prehemodialysis episodes of hyperkalemia were diet-induced. Hyperkalemic drugs and anuria were not associated with a higher risk of prehemodialysis hyperkalemia, but each one of 3 abnormalities, very high BUN (greater than 40 mmol/l), metabolic acidosis (TCO2 less than 15 mmol/l) and, in diabetics, severe hyperglycemia (serum glucose greater than 30 mmol/l), was associated with a statistically higher risk of hyperkalemia.