Basal insulin dose in 40 type 1 diabetic patients remains stable 1 year after educational training in flexible...

Basal insulin dose (BID) determination is the key to successful flexible insulin therapy (FIT). As our hypothesis was that BID changes over time, the primary objective of the present study was to determine the changes in BID 1 year after a therapeutic educational programme on FIT.

This single-centre retrospective study recruited the first 40 type 1 adult diabetic patients undergoing an educational FIT programme, which was conducted over a 4-day hospital stay and included a carbohydrate-fasting test.

Patients' BIDs decreased between Day 0 and Day 4 after the programme (0.31±0.11IU/kg/day vs 0.27±0.09IU/kg/day; P<0.0001), and was increased at 1 year (0.29±0.09IU/kg/day; P=0.004). There was no significant variation in prandial insulin requirements. A tendency toward a reduction in HbA(1c) was observed at 1 year (8.3±1.4% vs 8.1±1.6%; P=0.075), with a decrease by more than 0.5% in 37.5% of patients. Body weight increased at 1 year (66.9±10.4 kg vs 68.1±10.7 kg; P=0.003), and the gain was greater than 5% in 7.5% of patients. Frequency of mild hypoglycaemia either remained stable (40%) or decreased (30%). Only nine patients (baseline HbA(1c) 8.03±1.7%, baseline BID 0.27±0.09IU/kg/day) had BID increases more than 20%, with no changes in prandial insulin requirements and no distinctive phenotype. Baseline HbA(1c), and BID have an impact on the BID at 1 year of approximately 0.3IU/kg/day in most patients.

The stability of BID over 1 year, with values close to 0.3IU/kg/day associated with a trend towards improvement in HbA(1c), reduction in the frequency of mild hypoglycaemic episodes and absence of major weight gain, supports the relevance of FIT educational training.