Diabetes Care, Vol 19, Issue 6 559-563, Copyright © 1996 by American Diabetes Association
Does suppression of postprandial blood glucose excursions by the alpha-glucosidase inhibitor miglitol improve insulin sensitivity in diet-treated type II diabetic patients?
AB Johnson and R Taylor
Department of Medicine, University of Newcastle upon Tyne, UK.
OBJECTIVE: Insulin sensitivity is impaired in patients with type II
diabetes and is exacerbated by high mean blood glucose (BG). Potentially,
large postprandial swings in BG could result in further decrements of
insulin sensitivity. Because alpha-glucosidase inhibitors cause a marked
reduction in the amplitude of BG changes, the aim of this study was to
determine if such a BG-smoothing effect improves insulin sensitivity in
well-controlled type II diabetic subjects treated with diet alone. RESEARCH
DESIGN AND METHODS: Patients received either miglitol (BAY m 1099) (50 mg
three times daily) or placebo for 8 weeks in a randomized double-blind
parallel study. The miglitol (9 men, 2 women) and placebo (7 men, 3 women)
groups were well matched (mean +/- SD) for age, weight, and blood glucose
control (fasting BG, 6.4 +/- 1.0 vs. 6.9 +/- 1.6 mmol/l; HbA1, 7.7 +/- 1.0
vs. 7.9 +/- 0.4%; fructosamine, 0.99 +/- 0.08 vs. 1.07 +/- 0.17 mmol/l).
The glucose metabolic clearance rate was calculated during the last 30 min
of a 150 min glucose/insulin sensitivity test (glucose, 6 mg . kg-1 .
min-1; insulin, 0.5 U . kg-1 . min-1). RESULTS: There was no significant
improvement in metabolic clearance rate (0.21 +/- 0.27 vs. 0.16 +/- 0.35 l
. kg-1 . min-1) for the miglitol- and placebo-treated groups, respectively.
There were no statistically significant differences between miglitol and
placebo for changes from baseline in BG (0.1 +/- 0.1 vs. -0.1 +/- 0.2
mmol/l), HbA1 (0.1 +/- 0.1 vs. 0.3 +/- 0.1%), and fructosamine (-0.06 +/-
0.02 vs. -0.03 +/- 0.02 mmol/l). CONCLUSIONS: Alpha-glucosidase-induced
improvement in postprandial hyperglycemia does not result in increased
insulin sensitivity.