Table 1.
Results of the PubMed search for long-term studies (≥5 days) published between 2014 and 2016 on continuous closed-loop versus open-loop control during the day and night in the outpatient setting
| Study | Included (N) |
HbA1c (%) | Evaluated (N) |
Observation period | Physical activity during CL period | CL period | CGM | Algorithm | Defined glucose range (mmol/L) |
Time in hypoglycaemia (%) | Time in euglycemia (%) |
Time in hyperglycemia (%) |
|
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| OL | CL | ||||||||||||
| Leelarathna [35] | 21 adults | 7.6 | 17 | 7 d | 7 d | Advised not to drive or to undertake strenuous physical exercise under CL | 83.0% of the total time |
FreeStyle Navigator; Abbott |
Control to range MPC | [3.9, 10] | 3.7 CL vs 5.0 OL (ns)# | 74.5 CL vs 61.8 OL (s)# | 21.9 CL vs 30.5 OL (s)# |
| Russellab [29] | 20 adults | 7.1 | 20 | 5 d | 5 d | NR | 18–18 | G4 Platinum, Dexcom | Control to target MPC | [3.9, 10] | 4.1 CL vs 7.3 OL (s) | 79.5 CL vs 58.8 OL (s | 16.5 CL vs 33.8 OL (s) |
| Russellab [29] | 32 adolescents | 8.2 | 32 | 5 d | 5 d | NR | 18–18 | G4 Platinum, Dexcom | Control to target MPC | [3.9, 10] | 3.1 CL vs 4.9 OL (ns) | 75.9 CL vs 64.5 OL (s) | 21.0 CL vs 30.6 OL (s) |
| Ly¶ [36] | 21 adults/adolescents | 8.6 | 10 adults/adolescents in CL and 10 adults/adolescents in OL | 6 d | 6 d | NR |
07–07 (93% of total time during day and night) |
4 s sensor CL, Enlite sensor OL, Medtronic | PID | [3.9, 10] | 2.1 CL vs 2.4 OL (ns) | 69.9 CL vs 73.1 OL (ns) | 28.4 CL vs 24.8 OL (ns) |
| Thabit [30] | 33 adults | 8.5 | 32 CL, 33 OL | 12 w | 12 w | CL not used during physical activity during the initial 2 weeks |
00–24 (20.2 h/day#) |
FreeStyle Navigator, Abbott | Control to range MPC | [3.9, 10] | 2.9 CL vs 3.0 OL (s) | 67.7 CL vs 56.8 OL (s) | 29.2 CL vs 38.9 OL (s) |
| De Bock [37] | 8 adults/adolescents | 7.5 | 8 | 5 d | 5 d | NR | 00–24 |
Enlite II, MiniLink REAL-time sensor, Medtronic |
PID | [4.0, 9.9] | NI | 67.6 CL vs 58.7 OL (ns)# | NI |
| Renard [31] | 20 adults | 8.2 | 20 | 1 m | 1 m | NR | 00–24 | G4 Platinum, Dexcom | Control to target MPC | [3.9, 10] | 1.9 CL vs 3.2 OL (s) | 64.7 CL vs 59.7 OL (s) | 33.3 CL vs 37.0 (ns) |
| Bergenstal¶¶ [39] | 124 adults/adolescents | 7.4 | 124 | 2 w | 3 m | NR |
87.2% of the total time |
Enlite III, Medtronic | PID-IFB | (3.9, 10] | 3.3 CL vs 5.9 OL (NS) | 72.2 CL vs 66.7 OL (NS) | 24.5 CL vs 27.4 OL (NS) |
The studies had no restrictions regarding meals
HbA1c values and values for the percentage of time that glucose was within the defined range are reported as mean values unless they are labeled as median values
s significant, p ≤ 0.05
ns nonsignificant, p > 0.05
# Median, d days, w weeks, m months, CGM continuous glucose measurement, CL closed loop, OL open loop, NR no restrictions, NS not specified, MPC model predictive control, PID-IFB proportional integral derivative insulin feedback, NI no information
¶ During the day, research staff accompanied the participant
¶¶ During the CL period, the initial 6 days were spent in a hotel
aInsulin combined with the use of glucagon in CL modus
bIn adults, the OL period was performed in the outpatient setting, while the CL period was performed in an 8-km2 area accompanied by study staff, with the night spent in a hotel, where blood samples were drawn every 30 min. In adolescents, the OL and CL periods were performed in a diabetes camp