Background and Aims

The favorable impact of using more than 4 basal infusion rates (BIR) in open-loop delivery CSII systems remains unknown.

The aim of this work was to evaluate glycemic control according to the number of daily BIR in T1D patients using CSII.

Methods

Cross-sectional study of patients treated with CSII for ≧6 months, using a flash glucose monitoring system. Patients were divided into groups 1 (G1) and 2 (G2), with ≦4 and >4 BIR/24h respectively, and compared according to HbA₁c, TIR, TAR, TBR, GMI, coefficient of variation (CV) and hypoglycemia. Regression models were performed.

Results

We included 99 patients. Median (IQR) age was 30(17) years, with 28(70) months of CSII use. The number of different BIR were 4(3): 3(2) in G1 (n=55) and 6(2) in G2 (n=44). Groups were similar in age, sex, scholarity, weight and insulin analogue used. G2 had longer disease duration (14.5(12) vs 12(14) years, p=0.016), longer CSII use (51(77) vs 19.5(48) months, p<0.001) and higher basal total daily dose/Kg (0.30(0.13) vs 0.26(0.11) U/kg, p=0.006). No significant differences were found regarding HbA₁c, median glucose, GMI, TIR, TAR and CV. G2 patients had more hypoglycemia (47.4 vs 21.3%, p=0.019), more asymptomatic hypoglycemia (16.7 vs 1.8%, p=0.040) and higher TBR (6(9) vs 4(5)%, p=0.049). After adjusting for confounders, G1 maintained a lower risk of asymptomatic hypoglycemia (OR 0.06, p= 0.035, 95% CI 0.004;0.819).

Conclusions

Programming open-loop CSII devices with >4 BIR didn’t improve metabolic control, represented a risk factor for hypoglycemia and was an independent predictor of asymptomatic hypoglycemia.