Real-time continuous glucose monitoring significantly reduces severe hypoglycemia in hypoglycemia-unaware patients with type 1 diabetes

Abstract

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). HbA1c 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 HbA1c but failed to restore hypoglycemia awareness.

Figure 1

Annual rates of SH, requiring third-party help at baseline and 12 months after starting CGM. Also shown are the 12-month rates divided into those treated with or without LGS.