704-P: Time in Range and Time Below Range in Insulin-Treated Older Adults with Type 2 Diabetes

Hypoglycemia is the key limiting step for optimizing glycemic control in older adults. Continuous glucose monitoring (CGM) technology has not been well-evaluated in insulin treated older patients with type 2 diabetes (T2D) .

Methods: This prospective observational cohort study assessed of glycemic control using the FreeStyle Libre Flash CGM in insulin treated older adult patients with T2D. Subjects >65 years with T2DM on insulin therapy and HbA1c between 7% and 9%, with or without oral agents, were identified from a public hospital and a private diabetes clinic and invited by phone to participate (n= 462) . Patients treated with GLP1 agonists; eGFR <30 ml/min; Hb <11g/dL; ALT> 3x ULN; glucocorticoid use in the previous 3 months, and active malignancy were excluded. Participants worn the CGM continuously during a 6-weeks study period. They returned to clinic every 2 weeks for CGM data downloaded and new CGM placement, assessment of glycemic control and hypoglycemia. The investigators adjusted insulin treatment at each visit as needed. The first 2 weeks of CGM was considered baseline point and the last 2 weeks was the endpoint. The differences on time in range (TIR 70-180, mg/dl) and time below range (TBR, < 70 mg/dl) was tested using the Wilcoxon Signed-rank test with p <0.05.

Results: A total of 125 patients were randomized and 49 patients completed the 6 weeks follow-up (women=53.9%; age=72.8 ± 5.0 years; BMI=28.3±3.6 Kg/m²; eGFR=62.4 ± 16.6; ml/min A1c=8.0 ± 0.57%; GMI=7.1 ± 0.8%. The patients had a median TIR of 65% (min= 7%, max= 94%) at the baseline and 68% (min= 4%; max= 97%) at the endpoint. The median TBR was 3% (min= 0%, max= 23%) at the baseline and 2% (min= 0%; max= 18%) at the end of study. The TBR was significantly reduced after 6 weeks of CGM (p<0.01) .

Conclusions: An individualized approach may be possible using FreeStyle Libre Flash CGM to avoid overtreatment and undertreatment of older adults with T2D. CGM is a useful tool to reduce hypoglycemia in insulin older adults with T2D.