Effect of treatment with acarbose and insulin in patients with non-insulin-dependent diabetes mellitus associated with non-alcoholic liver cirrhosis

Aim: Non-insulin-dependent diabetes mellitus (type 2 diabetes) not responding to dietary treatment alone in patients with non-alcoholic liver cirrhosis is characterized by high postprandial hyperglycaemia. The control of postprandial hyperglycaemia in such patients, is generally achieved by the means of progressively higher doses of insulin, with an increasing risk of hypoglycaemia in the late postprandial period. The aim of this study was to evaluate the use of acarbose for the control of postprandial hyperglycaemia in 100 patients with well-compensated liver cirrhosis and type 2 diabetes treated with insulin. Methods: The study was double blind with randomization of treatments into acarbose (52 patients) vs. placebo (48 patients) with parallel branches over a period of 28 weeks. Results: All patients tolerated the treatments well and no significant variations in liver function tests were observed (< 5% vs. pretreatment). A significant reduction of several parameters was observed only after acarbose treatment: fasting glycaemia (173 +/- 28 vs. 146 +/- 19 mg/dl; p < 0.01), postprandial glycaemia (230 +/- 24 vs. 148 +/- 20 mg/dl; p < 0.01), mean glycaemia (206 +/- 20 vs. 136 +/- 13 mg/dl; p < 0.01), mean variation (180 +/- 14 vs. 51 +/- 10 mg/dl; p < 0.01), HbA(1c) (8.9 +/- 0.8 vs. 7.2 +/- 0.5; p < 0.05), C-peptide 2 h after a standard meal (4.5 +/- 1.9 vs. 2.8 +/- 1.7 ng/ml; p < 0.05), whereas the parameters did not change significantly after the placebo. After acarbose treatment a significant increase of intestinal voiding/week (+ 116% vs. + 10%; p < 0.01) and a parallel reduction of blood ammonia levels (- 52 +/- 9% vs. - 9 +/- 5%; P < 0.01) were observed. Conclusions: The results clearly document the good tolerability and the absence of toxic effects of acarbose on liver, due to the lack of both intestinal absorption and hepatic metabolism of the drug at doses in the therapeutic range. In fact, acarbose increases the peristalsis movements of the gut, stimulates the proliferation of the saccarolytic bacteria and simultaneously reduces the proliferation of proteolytic bacteria, thus resulting active in the reduction of blood ammonia levels. These effects of acarbose may be advantageously exploited in the treatment of type 2 diabetic patients with well-compensated non-alcholic liver cirrhosis.