EFFECTS OF A LOW-PROTEIN, LOW-PHOSPHORUS DIET ON METABOLIC INSULIN-CLEARANCE IN PATIENTS WITH CHRONIC-RENAL-FAILURE

The metabolic clearance rate (MCR) of insulin was studied in 17 nondia betic patients with advanced chronic renal failure (creatinine 479 +/- 15 mu mol/L, glomerular filtration rate 14.6 +/- 2.9 mL/min) before a nd after 3 mo of a low-protein, low-phosphorus diet (LPD) providing da ily per kilogram 0.3 protein of vegetal origin and 3-5 mg inorganic ph osphorus. The energy supply (146 kJ.kg(-1).d(-1)) was furnished mainly by carbohydrates. The diet was supplemented with a mixture of essenti al amino acids and ketoanalogues. The MCR of insulin was determined by using the euglycemic clamp technique. Before the diet the MCR of insu lin was low (450 +/- 127 mL.min(-1).m(-2)) but increased significantly at the third month (568.8 +/- 148 mL.min(-1).m(-2)), reaching values close to the MCR of control subjects (630 +/- 135 mL.min(-1).m(-2)). I dentical results have been described during hemodialysis of anephric p atients, leading us to hypothesize that an LPD reduces the production of dialyzable factors that interfere with peripheral insulin metabolis m.