Real-Time Continuous Glucose Monitoring Significantly Reduces Severe Hypoglycemia in Hypoglycemia-Unaware Patients With Type 1 Diabetes

OBJECTIVE: To evaluate the effect of continuous glucose monitoring (CGM) on the frequency of severe hypoglycemia (SH) in patients with established hypoglycemia unawareness. RESEARCH DESIGN AND METHODS: We conducted a retrospective audit of 35 patients with type 1 diabetes and problematic hypoglycemia unawareness, despite optimized medical therapy (continuous subcutaneous insulin infusion/multiple daily insulin injections), who used CGM for >1 year. RESULTS: Over a 1-year follow-up period, the median rates of SH were reduced from 4.0 (interquartile range [IQR] 0.75–7.25) episodes/patient-year to 0.0 (0.0–1.25) episodes/patient-year (P < 0.001), and the mean (±SD) rates were reduced from 8.1 ± 13 to 0.6 ± 1.2 episodes/year (P = 0.005). HbA(1c) was reduced from 8.1 ± 1.2% to 7.6 ± 1.0% over the year (P = 0.005). The mean Gold score, measured in 19 patients, did not change: 5.1 ± 1.5 vs. 5.2 ± 1.9 (P = 0.67). CONCLUSIONS: In a specialist experienced insulin pump center, in carefully selected patients, CGM reduced SH while improving HbA(1c) but failed to restore hypoglycemia awareness.