Table 1.
Studies reporting glycaemic metrics before and during COVID-19 social lockdown
| Study | Region | Adults/children (n) | Type | System | Change in glycaemic metrics |
|---|---|---|---|---|---|
| Bonora BM [17] | Italy | Adults (33) | T1D | FreeStyle Libre |
AG, mg/dL 177–160 (p = 0.005) %TIR 54–65.2 (p = 0.01) %TAR1 42.3–31.6 (p = 0.016) SD, mg/dL 58.9–53.2 (p < 0.05) |
| Capaldo B [19] | Italy | Adults (207) | T1D |
FreeStyle Libre (n = 130) Medtronic Guardian (n = 47) Dexcom G6 (n = 18) Eversense (n = 12) |
%TIR 55.6–58.2 (p = 0.002) %TBR2 1.42–0.58 (p < 0.001) %CV 35.9–34.7 (p = 0.001) |
| Schiaffini R [21] | Italy | Children (22) | T1D | Dexcom G6 |
%TIR 61.45–66.41 (p < 0.001) %TAR1 34.73–29.86 (p < 0.001) TDD, IU/day 7.9–5.3 (p < 0.001) |
| Christoforidis A [77] | Greece | Children (34) | T1D | Medtronic Enlite | %CV 39.5–37.4 (p = 0.011) |
| Fernández E [78] | Spain | Adults (307) | T1D | FreeStyle Libre |
AG, mg/dL 167–158 (p < 0.001) %TIR 57.8–62.5 (p < 0.001) %TBR1 4.9–5.5 (p < 0.001) %TAR1 37.3–32.0 (p < 0.001) eA1c 7.4–7.1 (p < 0.001) |
| Mesa A [15] | Spain | Adults (92) | T1D |
Free Style Libre (n = 75) Dexcom G5 (n = 17) |
%TIR 59.3–62.6 (p < 0.05) %TAR1 34.4–30.7 (p < 0.05) GMI, % 7.2–7.0 (p < 0.05) |
| Cotovad-Bellas L [79] | Spain | Adults (44) | T1D | FreeStyle Libre | No change during lockdown |
| Caruso I [80] | Italy | Adults (48) | T1D | FreeStyle Libre |
%TBR1 6.3–4.5 (p < 0.001) %CV 38.3–35.1 (p = 0.008) |
| Aragona M [81] | Italy | Adults (63) | T1D |
FreeStyle Libre (n = 52) Dexcom G6 (n = 11) |
AG, mg/dL 165–158 (p = 0.04) %TIR 58–61 (p < 0.05) %TAR1 38–34 (p < 0.04) GMI, % 7.2–7.0 (p = 0.016) |
| Dover AR [22] | UK | Adults (572) | T1D | FreeStyle Libre |
AG, mmol/L 9.6–9.3 (p < 0.001) %TIR 53–56 (p < 0.001) %TBR 3−3 (p = 0.005) %TAR1 42–39 (p < 0.001) eA1c 61–58 (p < 0.001) |
| Di Dalmazi G [82] | Italy |
Children ≤ 12 years (30) |
T1D |
Freestyle Libre (n = 2) Dexcom G5 or G6 (n = 28) |
SD 67.4–64.3 (p = 0.029) |
| Di Dalmazi G [82] | Italy |
Teenagers 13–17 years (24) |
T1D |
Freestyle Libre (n = 2) Dexcom G5 or G6 (n = 22) |
No change during lockdown |
| Di Dalmazi G [82] | Italy | Adults (76) | T1D |
Freestyle Libre (n = 41) Dexcom G5/G6 (n = 35) |
AG, mg/dL 164–160 (p = 0.001) %TIR 57.7–61.3 (p < 0.001) %TBR1 2.5–3.0 (p = 0.019) %TAR1 26.5–25.1 (p = 0.001) %TAR2 11.1–7.8 (p = 0.007) SD 63.0–59.6 (p = 0.016) eA1c, % 7.2–6.8 (p < 0.001) GMI,% 7.7–7.6 (p = 0.001) |
| Brener A [83] | Israel | Children (102) | T1D | Dexcom G5 | No change during lockdown |
| Pla B [84] | Spain | Adults (50) | T1D | FreeStyle Libre |
AG, mg/dL 160.3–150.0 (p < 0.001) %TIR 57.5–65.8 (p < 0.001) %CV 40.7–36.4 (p < 0.001) eA1c, % 7.2–6.8 (p < 0.001) GMI,% 7.2–6.9 (p < 0.001) |
| Prabhu Navis J [18] | UK | Adults (269) | T1D |
Freestyle Libre (n = 190) Dexcom G6 (n = 79) |
%TIR 57.5–59.6 (p = 0.002) %CV 37–36 (p = 0.003) |
| Barchetta I [14] | Italy | Adults (50) | T1D | FreeStyle Libre and other CGM, unspecified |
AG, mg/dL 154–165 (p = 0.027) %TIR 75–69 (p < 0.001) %TBR1 6–10 (p = 0.002) eA1c 7.3–7.5 (p = 0.031) |
| Predieri B [85] | Italy | Children (62) | T1D | Dexcom G6 |
%TIR 60.0–62.1 (p = 0.008) %TAR1 37.8–35.7 (p = 0.048) %TBR1 2.63–2.13 (p = 0.001) %TBR2 0.5–0.34 (p = 0.002) |
| Braune K [23] | Germany | Children (28) | T1D |
Freestyle Libre (n = 9) Dexcom G5/G6 (n = 6) Medtronic Guardian (n = 13) |
%TIR 46.9–56.3 (p = 0.016) %TAR1 21.3–13.9 (p = 0.013) |
| Potier L [20] | France | Adults (1378) | T1D | FreeStyle Libre | AG, mmol/L 9.1–8.7 (p < 0.001) |
| Boscari F [24] | Italy | Adults (79) | T1D |
FreeStyle Libre (n = 52) Dexcom (n = 16) Other CGM (n = 3) |
AG, mg/dL 161.1–156.3 (p = 0.001) %TIR 63.6–66.3 (p < 0.001) %TAR1 33.4–30.5 (p = 0.002) |
| Sánchez Conejero M [86] | Spain | Children (80) | T1D |
FreeStyle Libre (n = 15) Medtronic Guardian (n = 52) Dexcom G6 (n = 13) |
%TIR 72.1–74.8 (p = 0.01) %TAR2 4.6–3.7 (p = 0.038) %TBR1 4.6–3.2 (p < 0.001) %TBR2 1.2–0.7 (p < 0.001) %CV 35.8–33.1 (p < 0.001) |
| Rachmiel M [25] | Israel | Children (195) | T1D | Unspecified CGM |
AG, mg/dL 164–160 (p < 0.001) %TIR 59–63 (p < 0.001) %TAR1 32.0–38.6 (p = 0.005) %CV 37.1–35.6 (p = 0.002) eA1c, % 7.35–7.20 (p < 0.001) |
| Marigliano M [87] | Italy | Children (233) | T1D |
FreeStyle Libre (n = 98) Dexcom G6 (n = 100) SMBG (n = 35) |
AG, mg/dL 178.6–169.1 (p < 0.001) %TIR 52.6–58.0 (p < 0.001) %TAR1 43.4–38.0 (p < 0.001) SD 68.0–63.6 (p < 0.001) GMI, % 7.60–7.37 (p < 0.001) |
| Alharthi SK [26] | Saudi Arabia | Adults (101) | T1D | Unspecified CGM |
AG, mg/dL 180–159 (p < 0.001) %TIR 46–55 (p < 0.001) %TAR1 48–35 (p < 0.001) GMI,% 7.7–7.2 (p = 0.03) |
| van der Linden J [88] | USA | NA (65,067) | All | Dexcom G6 | %TIR 59–61 (p < 0.001) |
| Viñals C [16] | Spain | Adults (59) | T1D | Medtronic 640G + Enlite |
AG, mg/dL 153.2–147.8 (p < 0.001) %TIR 67.6–69.8 (p < 0.017) eA1c, % 6.94–6.75 (p < 0.001) |
Studies are listed in date order as disclosed on PubMed. Significant changes in glycaemic metrics from before to during COVID-19 lockdown are presented. Each number sequence indicates change from before to during lockdown with p value
AG average glucose, eA1c estimated HbA1c, %CV % coefficient of mean glucose, GMI glucose management indicator, %TIR percentage time in range 70–180 mg/dL (3.9–10 mmol/L), %TBR1 percentage time below range < 70 mg/dL (3.9 mmol/L), %TBR2 percentage time below range < 54 mg/dL (3.0 mmol/L), %TAR1 percentage time above range > 180 mg/dL (10 mmol/L), %TAR1 percentage time above range > 250 mg/dL (13.8 mmol/L), TDD total daily dose of bolus insulin, NA no information about demogaphics