Time in Tight Range (TITR) stratified by Coefficient of Variation (CV) in a cohort of patients with type 1 Diabetes Mellitus and Multiple Daily Injections. A real-life study.

OBJETIVE

To analyze the Time in Tight Range (TITR) (70-140 mg/dL) and the relationship between TITR-Time in Range (TIR) and assess their possible differences according to Coefficient of Variation (CV) in a cohort of patients with type 1 Diabetes Mellitus (DM) and Multiple Daily Injections in real life.

PATIENTS AND METHODS

355 adult users of Continuous Glucose Monitoring (CGM) with at least one HbA1c (October 1, 2023-October 1, 2024) and glucose data in the 90 days prior were included.

RESULTS

Age 46.9 years (SD 13.6); 57.2% male; time of evolution 21.6 years (SD 12.6). Mean TITR was 38.4% (SD 14.6) and 20.3% had a TITR ≥ 50%. The correlation TITR-TIR was strong (β = 0.83; CI 95% 0.8-0.87; R Adjusted 0.89; p < 0.001) and varied according to CV [CV ≤ 36% (β = 0.88; CI 95% 0.83-0.93; R Adjusted 0.89; p < 0.001); CV > 36% (β = 0.84; CI 95% 0.81-0.87; R Adjusted 0.93; p < 0.001)]. The cutoff value for TIR to discriminate TITR ≥ 50% varied according to CV [(CV ≤ 36% 75.9% (sensitivity 98%, specificity 94%, AUC 0.99, p < 0.001); CV > 36% 70.5% (sensitivity 100%, specificity 98%, AUC 0.99, p < 0.001)]. The variables that were independently associated with TITR in CV ≤ 36% group were TIR (β = 0.74; CI 95% 0.57-0.9; p < 0.001) and mean glucose (β = -0.11; CI 95% -0.21 to -0.01; p = 0.045). However, in CV > 36% group were time of evolution (β = 0.04; CI 95% 0.01-0.07; p = 0.008), HbA1c (β = -0.63; CI 95% -1.22 to -0.4; p = 0.036; CV (β = 0.33; CI 95% 0.24-0.41; p < 0.001) and TIR (β = 0.84; CI 95% 0.74-0.93; p < 0.001).

CONCLUSIONS

The correlation between TITR-TIR was strong and higher in patients with CV > 36%. Cutoff value for TIR to discriminate TITR ≥ 50% and factors that were associated with TITR also differ depending on CV. It is essential to take glycemic variability into account when interpreting metabolic control data.