Table 2.
Comparison of commercially available closed-loop systems using the CARES paradigm (32).
| CARES | 670G/780G | Control IQ | CamAPS FX | |
|---|---|---|---|---|
| Licensing | 7 years+ | 6 years+ | 1 year+ | |
| Availability | USA and Europe | USA & Europe | Europe | |
| Pump | Medtronic 670G / 780G | Tandem t:slim X2 | Dana RS, Dana-i | |
| Insulin | Rapid-acting | Rapid-acting | Ultra-rapid and rapid-acting | |
| Closed-loop term | Auto Mode | Control IQ | Auto mode | |
| Calculate | Algorithm | Treat-to-target proportional integral derivative with insulin feedback (670G); added fuzzy logic component (780G) | Treat-to-range predictive control | Treat-to-target MPC |
| Set-up | TDD, weight, basal rates, ICR, ISF, active insulin time. 7 days of manual mode |
TDD, weight, basal rates, ICR, ISF | TDD and weight | |
| Adaptive learning | Overall | Not specified by manufacturer | Overall, diurnal, meals | |
| Automated insulin delivery | Based on total daily insulin dose last 2-6 days | Based on pre-programmed basal rates | Based on adaptive learning | |
| Automated corrections used to supplement basal delivery | 670G: No780G: Yes | Yes | No | |
| Adjust | Glucose target | 670G: Target 6.7mmol/L non-customisable.780G: Customisable target of 5.5, 6.1, or 6.7mmol/L. | Target range 6.2 – 8.9mmol/L.Sleep range 6.2 – 6.7mmol/L.Non-customisable. | Target 5.8mmol/L.Customisable between 4.4-11mmol/L,adjustable in 0.1mmol/L increments. |
| Adjustable settings in CL | ICR, active insulin time, glucose target | Basal rates, ICR, ISF, target range | ICR, glucose target | |
| Non-adjustable in CL | Basal rates, ISF (automatically calculated and adapted) | Active insulin time (set at 5 hours) | Basal rates, active insulin time, ISF (all automatically calculated and adapted) | |
| Exercise mode | 670G: No780G: Yes | Yes | Yes | |
| Boost mode | No | No | Yes | |
| Revert | Sick day rules | —————————————–Recommended to revert to open loop for illness and/or ketones—————————————- | ||
| Automatically reverts to open loop if… | Prolonged hyperglycemia (670G only), max/min insulin delivery, loss of CGM data, sensor integrity concerns, lack of calibrations. | Loss of CGM data | Loss of CGM data or loss of pump connectivity | |
| Educate | Meal bolus | ———————————————-Pre-meal bolusing recommended for optimal outcomes——————————————— | ||
| Late bolusing can lead to insulin stacking and hypoglycaemia as CL insulin delivery increases in response to rising glucose | ||||
| Hypo treatment | ——————Consider treating hypoglycaemia with fewer carbohydrates depending on recent insulin delivery——————- | |||
| System optimisation | • System requires finger pricks for HCL functioning • Use of temp target will turn off automated corrections (780G only) • Extended bolus / combo bolus function not available in CL |
• Set sleep activity schedule overnight for tighter target • Adjust doses for individuals with shorter active insulin time • Extended bolus possible in CL, max 2 hours |
• Use exercise mode “Ease-Off” following hypoglycaemia • Use “Boost” mode during periods of high glucose • Extended bolus / combo bolus function not available in CL |
|
| Online training | No | Yes | Yes | |
| Sensor | Type of sensor | Guardian 3 | Dexcom G6 | Dexcom G6 |
| Calibrations | 670G: 4–6 per day780G: 1–2 per day | Rarely required (factory calibrated) | Rarely required (factory calibrated) | |
| Sensor life | 7 days | 10 days | 10 days | |
| Share | Remote monitoring | No (App in development for 780G) | Yes – Dexcom follow | Yes – Text Alert (Dexcom Follow planned for 2021) |
| Upload/Data sharing | Manual downloading | Automated cloud storage for Dexcom data; manual downloading for pump | Automated cloud storage to Diasend (Clarity in 2021) | |
| Remote bolusing | No | No | Yes | |
MPC, model predictive control; CGM, continuous glucose monitor; TDD, total daily insulin dose; ICR, insulin-to-carbohydrate ratio; ISF, insulin-sensitivity factor; CL, closed-loop.