Newer metrics like TIR are gaining momentum for measurement of glycemic control. The Medtronic 670G is the first commercial hybrid closed-loop (HCL) system for the management of T1D. We conducted a single-center retrospective chart review to compare continuous glucose monitor (CGM) metrics before and after initiation of 670G system in patients with T1D. Of 408 adult T1D patients who initiated 670G system during the study period, 139 patients were using an insulin pump with CGM for at least 3 months before the initiation of 670G system and had 6 months follow-up. Mean baseline age was 41±12, (60% women) with HbA1c of 7.6±0.9%. We analyzed the change in CGM data: % TIR (70-180 mg/dl), time-below-range (<70 mg/dl) and time-above-ranges (>180 mg/dl and >250 mg/dl) at 3 and 6 months of 670G system use. Use of 670G system significantly increased TIR (p<0.0001) and decreased time-below-range (p<0.0001) and time-above-range (p<0.0001) at 3 and 6 months compared to baseline (Figure). The mean percent time in auto-mode was 71% and 73% at 3 months and 6 months respectively. We conclude that HCL use in real-life significantly improves TIR and decreases hypo- and hyperglycemia.


H.K. Akturk: Advisory Panel; Self; Sanofi. Research Support; Self; Eli Lilly and Company, MannKind Corporation, REMD Biotherapeutics. Speaker's Bureau; Self; MannKind Corporation. D.A. Giordano: None. H. Joseph: None. S.K. Garg: Advisory Panel; Self; Eli Lilly and Company, Roche Pharma, Sanofi-Aventis, Zealand Pharma A/S. Research Support; Self; Eli Lilly and Company, WebMD. J.K. Snell-Bergeon: None.

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