The effect of basal–bolus therapy varies with baseline 1,5-anhydroglucitol level in people with Type 2 diabetes: a post hoc analysis

Aims: To investigate the impact of baseline 1,5-anhydroglucitol on the treatment effect of basal–bolus therapy in people with Type 2 diabetes. Methods: Post hoc analysis of onset 3, an 18-week, randomized, phase 3 trial evaluating the efficacy and safety of fast-acting insulin aspart in basal–bolus therapy (n = 116) vs. basal insulin-only therapy (n = 120) in people with Type 2 diabetes. The estimated treatment difference in change from baseline in HbA_1c was investigated for different cut-off values of baseline 1,5-anhydroglucitol (2, 3, 4, 5 and 6 μg/ml). Results: The estimated treatment difference in change from baseline in HbA_1c between basal–bolus therapy and basal insulin-only therapy was statistically significantly greater in participants with baseline 1,5-anhydroglucitol ≤3 μg/ml (n = 34) vs. >3 μg/ml (n = 198) [estimated treatment difference (95% CI): −1.53% (−2.12; −0.94) vs. −0.82% (−1.07; −0.57); P-value for interaction = 0.03]. The estimated treatment difference became more pronounced when comparing participants with 1,5-anhydroglucitol ≤2 μg/ml (n = 15) vs. >2 μg/ml (n = 217) [estimated treatment difference (95% CI): −2.26% (−3.15; −1.36) vs. −0.85% (−1.08; −0.62); P-value for interaction = 0.003]. For cut-off values ≥4 μg/ml, estimated treatment differences were numerically greater below the cut-off compared with above, although the interaction terms were not statistically significant. Conclusion: This analysis indicates that people with Type 2 diabetes with low 1,5-anhydroglucitol have an added treatment benefit with basal–bolus therapy compared with people with higher 1,5-anhydroglucitol. Further research is needed to clarify any clinical utility of these findings. Clinical Trials Registry No: NCT01850615.