Table 1

Baseline characteristics of studies evaluating the association between CGM-derived TIR and microvascular complications among patients with T2DM

CharacteristicsAll included studies
TIR and diabetic retinopathy
TIR and diabetic nephropathy
TIR and diabetic neuropathy
Sample size, n (range)466 (105–5901)2315.5 (281–5901)932.5 (281–5901)349 (105–740)
Sex (%)
Age, years, mean (SD)*59.3 (1.3)62.1 (0.99)61.6 (0.4)59.1 (2.8)
Baseline A1c, %, mean (SD)*8.2 (0.5)8.0 (0.6)7.8 (0.4)8.1 (0.6)
Duration of diabetes, years, mean (SD)†11.3 (1.0)11.8 (0.7)13.1 (0.2)11.0 (1.1)
Study location (n)
South Korea2
CGM device used (n)
Abbott Freestyle Libre4
Duration of CGM use (n)
3 days4
14 days4
3 and 6 days for GOLD (Medtronic) and iPro2 (Medtronic), respectively‡2
Two 6-day periods, separated by 2 weeks§1
CGM device calibrations (n)
Not applicable4
At least two times per day3
At least four times per day3
Not reported1
  • *Two studies (Yang et al21 and Kuroda et al22) reported the median age and the median baseline A1c in their study and hence were not included in the final calculation of mean age and average baseline A1c of the participants.

  • †Four studies (Yang et al,21 Kuroda et al,22 Guo et al,13 and Guo et al14) reported the median values for the duration of diabetes and hence were not included in the calculation of the mean duration of diabetes.

  • ‡Yoo et al17 and Kim et al18 used GOLD (Medtronic) and iPro2 (Medtronic) CGM over 3 and 6 days, respectively.

  • §Mayeda et al16 collected CGM data over two 6-day periods, separated by 2 weeks.

  • A1c, hemoglobin A1c; CGM, continuous glucose monitoring; T2DM, type 2 diabetes mellitus; TIR, time in range.