Dietary protein restriction in combination with angiotensin converting enzyme inhibitor improves insulin resistance in patients with chronic renal disease.

Insulin resistance (IR) and secondary hyperinsulinaemia are major risk factors of atherosclerosis and probably also of related glomerulosclerosis. Angiotensin converting enzyme inhibitors (ACEI), while improving IR in essential hypertension, do not improve it in patients with chronic renal disease. Thus, the combination of ACEI and low protein diet was evaluated. Thirty-eight patients with various kidney diseases and mild to moderate impairment of kidney function were included in the study. Thirteen of them suffered from IR. Their dietary protein intake was decreased from > or = 1.0 g/kg/d to 0.6-0.7 g/kg/d. Moreover, they were treated by ACEI enalapril at dosages of 2-10 mg/d depending on the absence/presence and severity of hypertension. The patients were followed for 8 months. No clinically relevant kidney disease progression (KDP) was found. IR patients improved remarkably. IR was examined by the oral glucose tolerance test and glucose, insulin and C-peptide determinations. Their increased plasma triglyceride, VLDL concentrations and proteinuria decreased, HDL concentration increased. Acid-base balance and anaemia did not change. It is concluded that protein restriction in combination with ACEI treatment improve IR and the associated dyslipoproteinaemia and proteinuria.