The current dosing guidelines suggesting TBD is ~ 50% of TDD and TBD = 0.5 U/kg (in T2DM) were based on uncontrolled studies. We have previously published separate controlled studies in pump-treated type 1 (n=39) and type 2 (n=30), multiple daily dosed-treated type 1 (n=49) and basal insulin only-treated type 2 diabetes (n=29). Herein we report the pooled results from these studies. In all studies the dose was titrated by CGM, the diet was the same (50% carbohydrate:30% fat:20%protein) and one meal/d was omitted to establish basal glucose control (except basal insulin-treated T2DM study in which the evening meal was limited to < 18:00h). Carbohydrate-to-insulin (CIR) was established by adjusting the pre-meal bolus so that the 2-4th h post-meal glucose was within 20% of the pre-meal. The resulting mean 24 h basal glucose of each study varied between 100 to 130 mg/dl. There was no significant difference (p > 0.10) in the mean TBD/TDD% and the mean U/kg between groups. When all subjects were then pooled, the mean TBD/kg was 0.232 U/kg (r = 0.601, n= 144) and the TBD/TDD%, 34.5% (r = 0.894, n=115). The mean CIR, g/U = 314/TDD (r = 0.829, n = 115) and 106/TBD (r = 0.747, n = 115). Basal estimation formulas are the same for T1 and T2DM. Current dosing estimation formulas recommend excessive basal and insufficient bolus insulin.


A.B. King: None.

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