Aims: In type 2 diabetes (T2D), insulin-induced weight gain may stem from a reduction in resting energy expenditure (REE). We sought to determine the early effects of insulin introduction on REE in 20 poorly controlled T2D patients.
Methods: After improving the glycaemia, REE was measured on Day 0 and Day 4 during two treatment regimens: bedtime insulin (n=10, group 1); and one off (3-day) intravenous insulin infusion (n=10, group 2).
Results: Both groups were similar in age, gender, BMI, C-peptide, HbA(1c) and initial REE. By Day 4, fasting glycaemia had similarly improved in both groups: group 1: -5.3+/-2.7mmol/L vs group 2: -5.8+/-4.2 mmol/L. In group 2, the second REE was measured 12h after stopping the intravenous insulin infusion, whereas subcutaneous insulin was maintained in group 1. REE did not change in group 2 (-1.3+/-6.5%), whereas it decreased significantly in group 1 (-8.0+/-7.0%; P<0.05).
Conclusion: Bedtime insulin led to an early and specific reduction in REE.