Introduction

The Stepping Up trial tested a model of care for insulin initiation in general practice consisting of training, clinical algorithms for insulin initiation and titration and diabetes educator (RN-CDE) support compared to usual care [1]. After the 12 month trial patients were followed for an additional 12 months.

Objectives

To compare HbA1c levels of the intervention (Stepping Up) and control group (usual care) over the 24 month study period.

Methods

Baseline characteristics were summarised for the 266 participants. An intention to treat approach was used. Linear mixed-effects models with random intercepts were used to estimate differences in mean outcome between groups using restricted maximum likelihood estimation, adjusted by baseline HbA1c levels. Individual participant data were treated as clusters and unstructured correlation structure used to account for repeated measures.

Results

Intervention and control groups were similar at baseline. 61% of patients were male, mean(SD) age 62 (10) years, diabetes duration 9 (5, 13) years. Baseline mean (95% CI) HbA1c was 8.9 (8.8 to 9.1)% for both groups. There was a clinically and statistically significant between group difference of HbA1c at 6 months (-0.6, 95% CI -0.9 to -0.3), 12 months (-0.7, 95% CI -1.0 to -0.3) and 18 months (-0.6, 95% CI -1.0 to -0.2).  At 24 months, the between group difference was -0.4 (95% CI -0.7 to 0.02) but was not statistically significant (p=0.065).  Mean (95% CI) HbA1c at 24 months in the intervention group was 7.7 (7.5 to 7.9)% and 8.0 (7.7 to 8.3)% in the control group.

Conclusion

Stepping Up was associated with improved glycaemic control compared to usual care for 18 months, suggesting that the model facilitated more timely treatment intensification.  Ongoing RN-CDE support and refreshment of the clinic staff in the model of care and current guidelines may be needed to facilitate ongoing treatment intensification.