Gastric emptying in Type II (non-insulin-dependent) diabetes mellitus before and after therapy readjustment: no influence of actual blood glucose concentration.

AIMS/HYPOTHESIS: Hyperglycaemia that is induced short-term slows gastric emptying in healthy subjects and patients with diabetes mellitus. Little information is available on the impact of longer-lasting, naturally occurring blood glucose increases and their reduction to euglycaemic values. We studied the relation between gastric emptying and pre-prandial and postprandial blood glucose concentrations in patients with Type II (non-insulin-dependent) diabetes mellitus and secondary failure to respond to oral hypoglycaemic treatment (a) before readjusting hypoglycaemic therapy and (b) 1 week thereafter.

METHODS

We studied 9 female and 1 male patient (age 60-78 years, BMI 21.9-32.5 kg/m2, diabetes duration 3-33 years, HbA1c 8.8-13.2%). Gastric emptying of a radiolabelled semisolid 1168 kJ meal was recorded scintigraphically.

RESULTS

Blood glucose concentration pre-prandial and postprandial was considerably lower subsequent to than before therapy readjustment in all patients (fasting, 7.9 mmol/l+/-1.5 SD vs 11.7+/-1.7 mmol/l; 60 min postprandial, 11.7+/-2.0 vs 15.4+/-2.2 mmol/l). By contrast, gastric emptying was unchanged (residual radioactivity in stomach 50 min postprandial 65.7+/-14.1% vs 66.5+/-12.9%). There was no relation between emptying and either fasting blood glucose concentration or its postprandial increase.

CONCLUSION/INTERPRETATION: The data do not support a major impact of actual, longer-lasting, naturally occurring blood glucose concentrations upon the rate of gastric emptying in patients with Type II diabetes.