Real-Time Continuous Glucose Monitoring Among Participants in the T1D Exchange Clinic Registry

OBJECTIVE To assess the frequency of continuous glucose monitoring (CGM) device use, factors associated with its use, and the relationship of CGM with diabetes outcomes (HbA(1c), severe hypoglycemia [SH], and diabetic ketoacidosis [DKA]). RESEARCH DESIGN AND METHODS Survey questions related to CGM device use 1 year after enrollment in the T1D Exchange clinic registry were completed by 17,317 participants. Participants were defined as CGM users if they indicated using real-time CGM during the prior 30 days. RESULTS Nine percent of participants used CGM (6% of children <13 years old, 4% of adolescents 13 to <18 years, 6% of young adults 18 to <26 years, and 21% of adults >= 26 years). CGM use was more likely with higher education, higher household income, private health insurance, longer duration of diabetes, and use of insulin pump (P < 0.01 all factors). CGM use was associated with lower HbA(1c) in children (8.3% vs. 8.6%, P < 0.001) and adults (7.7% vs. 7.9%, P < 0.001). In adults, more frequent use of CGM (>= 6 days/week) was associated with lower mean HbA(1c). Only 27% of users downloaded data from their device at least once per month, and <= 15% of users reported downloading their device at least weekly. Among participants who used CGM at baseline, 41% had discontinued within 1 year. CONCLUSIONS CGM use is uncommon but associated with lower HbA(1c) in some age-groups, especially when used more frequently. Factors associated with discontinuation and infrequent use of retrospective analysis of CGM data should be considered in developing next-generation devices and education on CGM use.