The effect of insulin delivery route on lipoproteins in type I diabetic patients on CAPD

Objective:To evaluate the influence of subcutaneous and intraperitoneal (IP ) insulin on plasma lipoproteins in type I diabetic (IDDM) patients with en d-stage renal failure (ESRD) treated with continuous ambulatory peritoneal dialysis (CAPD). Design: A before-after trial. Setting: University hospital outpatient care. Participants: Eleven IDDM patients with stabilized peritoneal dialysis, age 42.9 +/- 2.9 (SEM) years and duration of diabetes 31.4 +/- 3.4 years. Intervention: Two treatment periods during stabilized CAPD. All patients we re first treated with subcutaneous and then with IP insulin. The studies we re performed after a median time of 3 months on each treatment. Main Outcome Measures: Plasma lipids; apoproteins (Apo) A-I, A-II, and B; h igh-density lipoprotein (HDL) subfractions; glycemic status; and uremic sta tus. Results: After changing from subcutaneous insulin to IP insulin, plasma HDL cholesterol decreased (from 1.29 +/- 0.13 mmol/L to 0.96 +/- 0.06 mmol/L, p < 0.05), and the low density to high density lipoprotein (LDL/HDL) choles terol ratio increased (p < 0.05). The HDL cholesterol decreased in both HDL , and HDL, fractions, but significantly so only in HDL, (p < 0.01). ApoA-I (p < 0.05) decreased while the ApoB/ApoA-I ratio (p < 0.01) and the ApoA-I/ HDL-cholesterol ratio (p < 0.01) increased during IP insulin therapy. Intra peritoneal insulin resulted in significantly better glycemic control than s ubcutaneous insulin (p < 0.01). Conclusions: in diabetic patients on CAPD therapy, IP insulin, although ind ucing better glycemic control than subcutaneous insulin, was associated wit h lowered plasma HDL cholesterol and ApoA-I levels. The atherogenic potenti al is probably less than expected as the relative particle size of HDL rema ined unchanged.