This study evaluated patterns of daytime and nocturnal hypoglycemia during flash continuous glucose monitoring using the FreeStyle LibreTM system. Users scan the sensor to collect the current glucose, trend, and up to 8 hours of glucose readings which are automatically stored every 15 minutes. The internet-connected PC-based software uploads the de-identified 90-day reader data to a database. De-identified data from September 2014 to September 2017 of all sensors with at least 120 hours of operation were analyzed from 237,747 readers and 1,569,588 sensors worldwide (88% from Europe). Readers were ranked by scan frequency and allocated to 20 equally sized groups. The association of significant hypoglycemia (≤54 mg/dL) and scan rate were analyzed. Users performed a mean (SD) of 13.2 (9.0) glucose scans per 24 hours, with 11.5 (8.1) during the day (06:00-23:00) and 1.7 (1.5) during the night (23:00-06:00). Time in significant hypoglycemia (≤54 mg/dL) decreased from 24.2 to 15.2 minutes/day comparing low with high frequency scanners during the 17-hour day period (p<0.001), with a similar pattern overnight (19.0 and 12.7 minutes/night, p<0.001). When expressed as a proportion of time, hypoglycemia accounted for 2.4 to 1.5% of daytime glucose (for low to high frequency scanners), prevalence of night time hypoglycemia was 4.5 to 3.0%. The benefits of scanning frequently during the day are evident at night time.

H. Pryor: Employee; Self; Abbott. Employee; Spouse/Partner; Abbott. E.S. Budiman: Employee; Self; Abbott. Stock/Shareholder; Self; Abbott, AbbVie Inc. Y. Xu: Employee; Self; Abbott.

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