Intermediary metabolism, insulin sensitivity and insulin receptor status under comparable long-term therapy with insulin injections and continuous subcutaneous insulin infusion

Abstract

We have compared metabolic parameters, insulin sensitivity and insulin receptor status in 12 patients with insulin-dependent diabetes after 6 months treatment with insulin injection therapy and continuous subcutaneous insulin infusion therapy (CSII) in random order. Mean 24-h blood glucose, intermediary metabolite, plasma free insulin and counter-regulatory hormone concentrations were equivalent on the two regimes despite a significantly lower insulin dose on CSII (49.8 +/- 4.0 vs 39.3 +/- 2.2 U/24 h, P less than 0.01). When compared with a group of matched normal subjects, mean blood glucose and M-value, blood 3-hydroxybutyrate and free insulin concentrations were significantly higher on both regimes whilst blood alanine levels were depressed. Peripheral insulin sensitivity as assessed by the euglycemic clamp, basal hepatic glucose output, glucose carbon recycling, adipocyte insulin binding, adipocyte insulin sensitivity and lipogenesis were all similar after the two treatments. Insulin-stimulated initial rates of glucose uptake by adipocytes were higher after CSII (1.78 +/- 0.16 vs 2.35 +/- 0.27 pmol per cm2 cell membrane per 20 sec, P less than 0.005).