In hybrid closed-loop systems, algorithms control the automated insulin delivery (AID). Compared to conventional insulin administration, this not only has a favorable effect on HbA1c values, but also on patient-oriented outcome measures (PROMs). The results of two studies presented at this year’s EASD Annual Meeting underline the importance of AID systems in the treatment of patients with type 1 diabetes.
An AID (Automated Insulin Delivery) systemessentially consists of the following three components: Insulin pump, continuous glucose monitoring (CGM) and an algorithm that uses a stored program to calculate the insulin dosage based on current glucose values. The latter, i.e. the implementation of artificial intelligence (AI), brings decisive advantages for certain subpopulations of type 1 diabetics in particular. Researchers from the UK and Denmark investigated the effects of an AID system in adults with type 1 diabetes whose HbA1c was above the target values despite an insulin pump and CGM [1]. The conclusion was consistently positive. In another study, a Spanish research team investigated the effects of hybrid closed-loop systems on patient-reported outcome measures (PROMs) in everyday life. The AID systems were also convincing in this respect and performed better than conventional treatment [2].
Advantageous glycemic control compared to insulin pump and CGM
Achieving glycemic targets is sometimes a challenge even when using an insulin pump and CGM. It is known that AID systems can lead to an improvement in glycemic control, but there are few data from randomized trials in patients with type 1 diabetes who had an HbA1c ≥58 mmol/mol (7.5%) despite insulin pump and CGM/ isCGM. In a 14-week randomized controlled open-label study, 40 study participants were assigned in a 1:1 ratio to a study arm with a hybrid closed-loop system** or continuation of the previous treatment [1]. At baseline, the average age of the participants was 52±11 years, the HbA1c was 67±7 mmol/mol (8.3 ± 0.6%) and the duration of diabetes was 29 ± 13 years. The primary endpoint was the difference in time in range (TIR: 3.9-10.0 mmol/L) between the two groups from baseline to week 14, as measured by CGM data.
** Medtronic MiniMedTM 780G
As a result, TIR increased by 18.7 ± 8.4% in the AID group, while it remained unchanged in the conventional treatment group (“between-group” difference, p<0.001) (Table 1) . Remarkably, a TIR ≥70% was achieved by 80% of the participants in the AID group, but only by 10% of those with standard treatment (p<0,001). During sleep (24 h to 6 h), TIR increased by 25.2 ± 13.3% in the AID group (from 60.8% to 86.0%, p<0.001), while there was no significant change in the standard treatment group (from 58.6% to 54.8%, p=0.45). The “time below range” (TBR: <3.9 mmol/L) decreased in both groups, without a “between-group” difference manifesting itself. HbA1c levels decreased in the AID group from 67 to 57 mmol/mol (8.3 to 7.3%, p<0.001), while in the other group they decreased from 68 to 67 mmol/mol (p=0.71); the between-group difference was found to be significant (p<0.001). There were no differences between the two groups in terms of changes in body weight or daily insulin dose. There were no cases of severe hypoglycemia or diabetic ketoacidosis during the course of the study. In summary, it can be stated that type 1 diabetics who do not reach their glycemic targets despite the insulin pump and CGM can benefit considerably from the use of an AID system.
Hybrid closed loop also pays off in terms of PROMs
Between November 2021 and May 2022, 84 patients with type 1 diabetes (female: n=53) undergoing outpatient treatment at the Department of Endocrinology and Nutrition at the Arnau de Vilanova University Hospital in Lleida (E) started using a hybrid closed-loop system$ [2]. At baseline, all patients used a glucose monitoring device, 70.2% (n=59) already had an insulin pump and 29.8% (n=25) used conventional subcutaneous insulin. The glucose parameters were recorded 14 days before each patient had a consultation using the web application linked to the blood glucose meter. The PROMs were recorded using the following questionnaire tools:
- ViDa1 (Vida con Diabetes tipo 1) for quality of life
- PSQI (Pittsburgh Sleep Quality Index) for sleep quality
- DTQS (Diabetes Treatment Satisfaction Questionnaire change) for the change in satisfaction with treatment.
$ Medtronic Minimed 780G or Tandem t:slim X2 with Control IQ system or Roche Accu-Chek Insight with Diabeloop algorithm
After six months, Cegarra Baños et al. the data from 81 of the patients. There were significant improvements in HbA1c (7.3 ± 0.9% vs. 6.8 ± 0.7%, p<0.001), as well as in time to target (64±16.3% vs. 75.1±12%, p<0.001). The following parameters also improved:
- Time in the range of hypoglycemia 55-70 mg/dl (2.9 ± 2.3% vs. 1.5 ± 1.1%, p<0.001)
- Time in the range of hyperglycemia 180-250 mg/dl (22.3 ± 8.1% vs. 17.4 ± 8%, p<0,001) bzw.>250 mg/dl (10.5 ± 10.4% vs. 5.87 ± 7.2%, p<0.001)
- total scores in ViDa1 (105.7 ± 12 vs. 104 ± 16.6, p=0.4).
Although the overall PSQI scores (p=0.6) did not change, there was an improvement in self-management as measured by ViDA1 (p=0.01). With regard to stressful diabetes-related thoughts, there was also a tendency towards an improvement (p=0.06). In those patients who had impaired sleep quality at baseline (PSQI <5), there was a significant improvement after six months (p=0.03); in the others, the sleep quality measured at baseline was maintained. It is also noteworthy that there was a significant increase in satisfaction with treatment (DTQS) compared to baseline (14.3 ± 4.16, p<0.001). The authors suggest considering not only glycemic parameters but also other factors, such as the PROMs recorded in this study, in patients starting to use a hybrid closed-loop system in order to evaluate the patient-side benefits of this diabetes technology.
Congress: EASD Annual Meeting
Literature:
- Christensen MB, et al: Automated insulin delivery use in adults with type 1 diabetes not meeting glycaemic targets despite treatment with insulin pump and CGM: a randomized controlled trial. Diabetologia 2023; 66 (Suppl 1): S1-S536.
- Cegarra Baños M, et al: Patient reported outcome measures after six months of hybrid closed loop therapy. SO 59 How does AID aid the patients? Diabetologia 2023; 66 (Suppl 1): S1-S536.
HAUSARZT PRAXIS 2023; 18(11): 24-25 (published on 20.11.23, ahead of print)
