The Number of Basal Rates Required to Achieve Near-Normal Basal Glucose Control in Pump-Treated Type 2 Diabetes

Abstract

It has been reported that most pump-treated patients with type 2 diabetes require only two or fewer basal rates. Using daily continuous glucose monitoring (CGM)-directed titration, this premise was re-evaluated at near-normal glycemic control. Thirty subjects who were insulin-naive (n = 10), on basal insulin (n = 10), or on basal-bolus insulin therapy (n=10) ate a fixed diet. The basal rate was started as a single rate and then adjusted to a basal glucose goal of 70-130 mg/dL. The insulin-to-carbohydrate ratio (ICR) (in g/U) was adjusted to 2-4-h postmeal CGM glucose goal of 80-120% of premeal glucose. The mean (SE) CGM basal glucose was 99.9 (4.9) mg/dL, and 4.5% (1.4%) of the readings were <70 mg/dL. The mean 2-4-h postmeal glucose was 113.3% (4.8%) of the premeal glucose. Only six subjects (20%) required two basal rates, while the remainder needed only one. The mean (SE) dosing relationships were as follows: total basal dose (TBD) (in U/day) = 0.226(0.018) × weight (in kg); TBD (in U/day) = 0.339(0.012) × total daily dose (TDD) (in U/day); ICR (in g/U) = 126(8)/TBD (in U/day); and ICR (in g/U) = 365(14)/TDD (in U/day). This study confirms that one basal rate is adequate for the majority of subjects with type 2 diabetes. The mathematical proportionality between dosing factors closely agrees with those obtained in CGM-titrated pump-treated type 1 diabetes but differs from those derived from clinical studies in which insulin titration was based on infrequent self-monitored plasma glucose testing and while on an unstructured diet.