Journal of Diabetes Science and Technology · Oct 28, 2026
Changes in CGM-Derived Glycemic Metrics and Triglyceride-Glucose Index During Ramadan in Adults With Type 2 Diabetes Using Real-Time Continuous Glucose Monitoring
By Al Hayek A, Al Zahrani WM, Al Ajlouni M et al.
PURPOSE: To evaluate longitudinal changes in continuous glucose monitoring (CGM)-derived glycemic metrics, glycemia risk indices (GRIs), triglyceride-glucose (TyG) index, and diabetes self-management before, during, and after Ramadan fasting in adults with type 2 diabetes (T2D) receiving non-intensive diabetes therapy and using real-time CGM (rtCGM). METHODS: This ambispective longitudinal cohort study included 110 adults with T2D managed at a tertiary diabetes center in Riyadh, Saudi Arabia. The study combined retrospective ascertainment of pre-enrollment data with prospective follow-up from enrollment during Ramadan through the post-Ramadan period. Glycemic outcomes were assessed across pre-Ramadan, Ramadan, and post-Ramadan periods using CGM-derived metrics, including time in range (%TIR₇₀₋₁₈₀), time above range, glucose variability, GRI, and hypoglycemia indices. The TyG index and Perceived Diabetes Self-Management Scale (PDSMS) were also evaluated. RESULTS: Compared with the pre-Ramadan period, median %TIR₇₀₋₁₈₀ increased significantly during Ramadan from 60.8% to 65.0% (P < .001), while median sensor glucose decreased from 187 to 175 mg/dL (P < .001). Glucose variability also improved during Ramadan (36.5% vs 32.0%, P < .001), accompanied by lower GRI values (38.0 vs 35.3, P < .001). Severe hypoglycemia exposure (time below range, %TBR<54) remained unchanged (P = .358), although mild hypoglycemia exposure increased modestly. The TyG index decreased during Ramadan (9.65 vs 9.55, P = .003), whereas PDSMS scores increased from 27.0 to 29.0 (P < .001). Several glycemic and metabolic parameters demonstrated post-Ramadan rebound toward pre-Ramadan levels. No hospitalizations or treatment-escalation events occurred during Ramadan. CONCLUSION: Improved glycemic control, reduced hyperglycemia exposure, and enhanced diabetes self-management were observed during Ramadan among selected adults with T2D receiving non-intensive diabetes therapy, rtCGM, and structured Ramadan-focused support, with stable severe hypoglycemia exposure despite a modest increase in mild hypoglycemia.