Abstract
In this study we evaluated which injection time is preferable: morning or evening insulin in the combination glibenclamide plus a single low‐dose injection of biphasic insulin (Insuman Combitard 25/75) in Type 2 patients with secondary failure to sulphonylurea treatment. Forty one patients within 25% of ideal body weight (IBW) were randomised in an open controlled study. Insulin was given as a single dose 0.15 U/kg in the morning (am) or at night (pm). Efficacy data from 37 patients were calculated. Eighteen patients received am insulin and 19 received pm insulin. Glibenclamide was continued in maximum dose of 10 mg in the am, 5 mg in the pm. Compared with baseline values, fasting, mean post‐prandial and mean 11 hr glucose expressed as area under curve (AUC) plasma glucose were decreased by 27%, 17% and 18% respectively (p< 0.001) following pm insulin. Treatment with am insulin revealed no significant change in fasting glucose but there were decreases of 25% and 24% respectively (p< 0.001) in mean postprandial and AUC glucose. Fructosamine and lipids decreased significantly following pm insulin (p<0.05, p<0.01) while AUC for c‐peptide decreased following am insulin (p=0.014) but did not change following pm insulin. Cholesterol decreased significantly following am insulin (p=0.002). No hypoglycaemia was observed following am insulin. Target glucose values were not achieved with either regimen.
It was concluded that am and pm insulin both improved metabolic control but this was achieved with am insulin with a possible β‐cell sparing effect in the absence of hypoglycaemia.