Comparison of apolipoprotein B100 metabolism between continuous subcutaneous and intraperitoneal insulin therapy in type 1 diabetes.

Objective: In type 1 diabetic patients, the replacement of sc insulin infusion with ip insulin infusion restores the normal physiological gradient between the portal vein and the peripheral circulation, which is likely to modify lipoprotein metabolism. Design: To check this hypothesis, we performed two apolipoprotein (apo) B100 kinetic studies in seven type 1 diabetic patients, first under sc insulin infusion and then 3 months after the beginning of ip insulin infusion. Results: Glycemic control was similar under sc insulin infusion and ip insulin infusion, as assessed by glycated hemoglobin A(1c) and the capillary glycemic curve determined during the kinetic study. Very low-density and intermediate-density lipoprotein apoB100 pool size, production rate, and fractional catabolic rate (FCR) were similar under sc insulin infusion and ip insulin infusion. The low-density lipoprotein apoB100 FCR tended to decrease under ip insulin (0.45 +/- 0.06 vs. 0.55 +/- 0.11 pool/d), but the difference did not reach statistical significance (95% confidence interval for the difference, -0.33, 0.11). The low-density lipoprotein apoB100 pool size and production rate remained unchanged under ip insulin infusion compared with sc insulin infusion. Conclusion: In type 1 diabetic patients, the replacement of sc insulin infusion with ip insulin infusion does not induce profound modifications of apoB100-containing lipoprotein production and FCRs.