Endocrine Abstracts

Background: Type 1 diabetes is a chronic disease requiring constant management and a disciplined lifestyle, especially in children. Real-time continuous glucose monitoring system (RT-CGMS) can be a useful tool in maintaining good glycemic control. In our medical centre, beginning with January 2019, a National Program for free distribution of RT-CGMS has been set in motion. The results from one of our previous studies indicated a significant increase in glycosylated haemoglobin (HbA1c) levels after 6 months from RT-CGMS initiation in children already on RT-CGMS at baseline, presumptuously due to a poor metabolic control during the summer months. The present study analyses this hypothesis.

Methods and materials: The analysis included 73 patients, aged under 18 upon entering the national program, who were divided into two groups, depending on the existence of a RT-CGMS at baseline: with previous RT-CGMS at baseline (RT-CGMS+) and without a RT-CGMS at baseline (RT-CGMS-). The baseline medical visit for these patients was done in June and July 2019 when they received free glucose monitoring sensors. The 3 months visit was considered at 90 ± 30 days from baseline. This is a unicentric, prospective cohort study.

Results: We evaluated 73 patients, 36 women (49.3%), mean age 11.2 ± 3.8 years (range: 2.3–17.8 years), mean diabetes duration 4.7 ± 3.1 years. The RT-CGMS + group has 26 subjects, mean age 11.1 ± 4.1 years, mean diabetes duration 5.4 ± 3.1 years, with a mean HbA1c 7.0 ± 0.5% (53 mmol/mol) at baseline. The RT-CGMS- group has 47 subjects, mean age 11.3 ± 3.6 years (P = 0.90 vs RT-CGMS+), diabetes duration 4.3 ± 3.1 years, and HbA1c 7.6 ± 1.1% (60 mmol/mol, P = 0,016 vs RT-CGMS+) at baseline. There was a significant increase in HbA1c after 90.2 ± 8.1 days in the RT-CGMS+ group reaching 7.5 ± 0.6% (58 mmol/mol, P < 0.01 vs baseline). The HbA1c variation did not change significantly in the RT-CGMS- group, with a value at 3 months of 7.8 ± 1.1% (62 mmol/mol, P = 0.075 vs baseline).

Conclusions: The results of the three months follow-up over the summer for the two patient groups indicated that RT-CGMS initiation in patients previously not exposed to RT-CGMS cancels the increase of HbA1c levels registered in patients previously exposed to RT-CGMS, who continue to use it for the same study period. This finding is consistent with the poor glycemic control observed during the summer in most patients, and especially in teenagers.