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Diabetology & Metabolic Syndrome logoLink to Diabetology & Metabolic Syndrome
. 2026 May 25;18:160. doi: 10.1186/s13098-026-02194-0

Long-term effectiveness of automated insulin delivery in young people with type 1 diabetes: a meta-analysis

Zhihui Sun 1,2,#, Sihan Yang 3,#, Le Gao 4,5,, Lin Dou 6,, Baoqi Zeng 2,3,6,
PMCID: PMC13386754  PMID: 42185906

Abstract

Background

To evaluate the long-term glycemic outcomes of automated insulin delivery (AID) systems in young people (age ≤ 25 years) with type 1 diabetes.

Methods

We searched PubMed, Embase, the Cochrane Library, and ClinicalTrials.gov from inception to October 25, 2025. Clinical trials and real-world studies with intervention periods of ≥ 12 months were included. The primary outcomes were changes in time in range (TIR, 3.9–10.0 mmol/L) and HbA1c. Secondary outcomes included time in tight range (TITR, 3.9–7.8 mmol/L), time below/above range metrics (TBR1 < 3.9 mmol/L; TBR2 < 3.0 mmol/L; TAR1 > 10.0 mmol/L; TAR2 > 13.9 mmol/L), mean sensor glucose, glucose coefficient of variation (CV), and glucose standard deviation (SD). Data were pooled using random-effects models to calculate mean differences (MDs) with 95% confidence intervals (CIs).

Results

A total of 26 studies involving 16,596 participants were included. The use of AID systems significantly increased TIR by 11.56% (MD 11.56%, 95% CI 10.20 to 12.93; p < 0.001), equivalent to 166 additional minutes per day, and reduced HbA1c by 0.52% (MD: -0.52%; 95% CI: -0.63 to -0.40; p < 0.001). AID systems significantly increased TITR by 9.11% (MD 9.11%, 95% CI 7.59 to 10.63; p < 0.001). Significant reductions were also observed in TBR1 (MD -0.69%, 95% CI -1.33 to -0.06), TBR2 (MD -0.31%, 95% CI -0.54 to -0.08), TAR1 (MD -9.87%, 95% CI -11.56 to -8.17), and TAR2 (MD -5.21%, 95% CI -6.39 to -4.03). Mean sensor glucose decreased by 15.05 mg/dL (95% CI -17.99 to -12.11). Glucose CV was reduced by 0.99% (MD -0.99%, 95% CI -1.76 to -0.21) and glucose SD decreased by 5.80 mg/dL (MD -5.80 mg/dL, 95% CI -7.00 to -4.59).

Conclusions

AID systems provide substantial and sustained improvements in glycemic control over ≥ 12 months in young people with type 1 diabetes, supporting their long-term clinical implementation.

Trial registration

This study was registered on PROSPERO (CRD420251150271).

Supplementary Information

The online version contains supplementary material available at 10.1186/s13098-026-02194-0.

Introduction

Type 1 diabetes (T1D) imposes a substantial lifelong management burden on young people and their families [1]. Maintaining optimal glycemic control remains challenging despite advances in insulin formulations, delivery devices, and continuous glucose monitoring (CGM) technologies [2]. The American Diabetes Association recommends a target glycated hemoglobin (HbA1c) level of less than 7% for most pediatric patients [3], corresponding to more than 70% time in range (TIR, 3.9–10.0 mmol/L) as measured by CGM [4, 5]. The International Society for Pediatric and Adolescent Diabetes further recommends an HbA1c target of < 6.5% for individuals using AID systems under appropriate management conditions [6]. However, real-world data indicate that fewer than 20% of young people with T1D achieve these goals [7].

Automated insulin delivery (AID) systems represent a transformative technological advancement in diabetes management [8]. These systems integrate CGM, insulin pumps, and control algorithms to automatically modulate insulin infusion in response to real-time glucose levels [9]. Previous meta-analyses, including our own work, have demonstrated that AID systems significantly improve glycemic control in young people (age ≤ 25 years) with T1D compared to conventional treatment methods [1014]. However, these analyses primarily focused on short-term outcomes (typically 3 months or less) from randomized controlled trials (RCTs) conducted in controlled settings.

The long-term effectiveness of AID systems in real-world clinical practice remain insufficiently investigated [15]. While RCTs provide evidence of efficacy under ideal conditions, real-world evidence (RWE) studies offer valuable insights into how these systems perform in diverse clinical settings with varied patient populations and practice patterns [16]. This is especially important for young people, a population with distinct physiological and behavioral characteristics that may influence technology use and outcomes [17]. Understanding the sustained benefits and potential risks of AID technology over extended periods is crucial for clinical decision making and patient education [18]. Given the limited evidence regarding long-term outcomes of AID systems in pediatric populations, we conducted this systematic review and meta-analysis to evaluate the glycemic outcomes of AID systems over extended periods (≥ 12 months) in young people with T1D by synthesizing evidence from both clinical trials and real-world studies.

Methods

Search strategy and study selection

This systematic review was prospectively registered on the International Prospective Register of Systematic Reviews (PROSPERO) under registration number CRD420251150271. We conducted a comprehensive literature search across multiple electronic databases, including PubMed, Embase, the Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov, from inception until October 25, 2025. The search strategy incorporated a combination of Medical Subject Headings (MeSH) and keywords related to “type 1 diabetes”, “closed-loop system”, “automated insulin delivery”, “artificial pancreas”, “child”, and “adolescent”. The full search strategy is available in the Supplementary Material. No language restrictions were applied. Additionally, the reference lists of retrieved articles and relevant reviews were manually screened to identify additional eligible publications.

Studies were included if they met the following criteria: (1) participants were young people (age ≤ 25 years) diagnosed with T1D; (2) the intervention involved any AID system; (3) the comparator was conventional insulin therapy, such as multiple daily injections (MDI), insulin pump without automation (CSII), or sensor-augmented pump therapy (SAP) with or without predictive low-glucose suspend (PLGS); (4) reported outcomes included TIR or HbA1c; (5) the study design was a RCT, cohort study, or before-after study; and (6) the study duration was at least 12 months. We excluded studies with intervention periods shorter than 12 months, those with insufficient outcome data, studies involving fewer than 10 participants using AID. If multiple reports from the same study with different follow-up durations were identified, only the one with the longest follow-up was included to avoid duplication.

Outcome measures

The primary outcomes were the TIR (3.9–10.0 mmol/L) and HbA1c. Secondary glycemic outcomes included time in tight range (TITR; 3.9–7.8 mmol/L), time below range Level 1 (TBR1; <3.9 mmol/L), time below range Level 2 (TBR2; <3.0 mmol/L), time above range Level 1 (TAR1; >10.0 mmol/L), time above range Level 2 (TAR2; >13.9 mmol/L), mean sensor glucose, coefficient of variation (CV, %) of glucose, and standard deviation (SD, mg/dL) of glucose. The definitions of CGM-derived glycemic metrics were based on the international consensus recommendations [4].

Data extraction and quality assessment

Two reviewers (ZS and SY) independently screened titles and abstracts, and potentially relevant full-text articles were retrieved for further evaluation. Discrepancies were resolved through discussion or by consulting a third reviewer (ZS). Data were extracted using a standardized form, which included first author, publication year, country, study design, sample size, participant characteristics (e.g., age, sex, diabetes duration, baseline HbA1c), type of AID system and comparator, study duration, and outcome data.

The methodological quality of RCTs was assessed using the Cochrane Risk of Bias Tool (RoB 2) [19], while non-randomized studies were evaluated using the Risk of Bias in Non-randomized Studies of Interventions (ROBINS-I) tool [20].

Data synthesis and analysis

Meta-analyses were performed using DerSimonian and Laird random-effects models to calculate pooled mean differences (MDs) and 95% confidence intervals (CIs) for continuous outcomes. For dichotomous outcomes, we calculated pooled relative risks (RRs) with 95% CIs. When studies reported medians and interquartile ranges (IQRs) instead of means and standard deviations (SDs), we assumed the median to be equivalent to the mean and estimated SDs by dividing IQRs by 1.35, as recommended by the Cochrane Handbook [21]. For before-after studies that did not report 95% CI or standard error (SE) of MD, we calculated SEs from pre- and post-intervention values based on group means and SDs assuming a correlation coefficient of 0.5 [12, 22].

Heterogeneity among studies was assessed using the Cochran’s Q test and quantified with the I²statistic. I²values of 25%, 50%, and 75% were interpreted as indicating low, moderate, and high heterogeneity, respectively [23]. Subgroup analyses for TIR and HbA1c were conducted to explore potential sources of heterogeneity based on study design, type of AID system, study duration, type of comparator, age, and mean baseline HbA1c. Potential publication bias was assessed visually using funnel plots and statistically using Egger’s test when at least 10 studies were available for an outcome. All statistical analyses were conducted using Stata version 17.0 (StataCorp, College Station, TX).

Results

Literature search and study characteristics

The initial systematic literature search identified 2219 records from electronic databases and other sources. After removing 686 duplicates, 1533 records underwent title and abstract screening. Following this, 105 full-text articles were assessed for eligibility. Ultimately, 26 studies, comprising a total of 16,596 participants, met the inclusion criteria and were included [2449]. Two studies that exclusively enrolled youth with elevated baseline HbA1c were excluded from the quantitative meta-analysis due to a high risk of bias [35, 39]. The detailed study selection process is illustrated in a PRISMA flow diagram (Figure S1).

The characteristics of the included studies are summarized in Table 1. Among the 26 studies, 2 were RCTs, 6 was single-arm trial, while 18 were RWE studies, including both prospective and retrospective designs. All RWE studies were uncontrolled before-after designs. The sample sizes ranged from 19 to 13,922 participants. Study duration varied from 12 to 48 months, with 6 studies conducted over 24 months or longer. The mean age of participants ranged from 2.4 to 21.0 years, and baseline HbA1c values ranged from 7.1% to 10.5%. Various AID systems were evaluated, including MiniMed 780G, Control-IQ, MiniMed 670G, CamAPS FX, Omnipod 5, and others. Conventional therapy comparators included SAP, CSII, MDI, and mixed insulin regimens.

Table 1.

Study characteristics and patient demographics of included studies

Study Participant characteristics* Study design Type of automated insulin delivery Comparison/Prior therapy No of patients Country Study duration
McVean 2023 [38] Age 11.8 (2.8) [7–17] years; 64 male, 49 female; newly diagnosed; HbA1c 10.3% (1.4) Parallel RCT, NCT04233034 Control-IQ or MiniMed 670G or MiniMed 780G CSII or MDI 113 USA 12 months
Ware 2024a [49] Age 14 (2) [10–16.9] years; 47 male, 34 female; diabetes duration NR; HbA1c 7.3% (1.2) Parallel RCT (extension phase), NCT02871089 FlorenceM or/and CamAPS FX MDI 81 UK 48 months
Ware 2024b [48] Age 6.6 (1.5) [1–7] years; 23 male, 26 female; diabetes duration NR; HbA1c 7.1% (0.6) Single-arm trial, NCT03784027 CamAPS FX SAP 49 Multiple countries (UK, Austria and Germany) 18 months
Beato-Víbora 2022 [24] Age ≤ 25 years; 49 male, 86 female; diabetes duration 21 (12) years; HbA1c 7.30% (0.89) Prospective before–after RWE MiniMed 780G CSII (73.3%) or MDI (26.7%) 135 Spain 12 months
Del Valle Rolón 2023 [28] Median age 13.3 [IQR 9.9–15.5] years; 56 male, 59 female; median diabetes duration 5 (IQR 1.7–8) years; median HbA1c 7.8% (6.9–8.8) Retrospective before–after RWE Control-IQ CSII (82%) or MDI (18%) 115 USA 12 months
Varimo 2021 [47] Age 9.7 (3.2) [3–16] years; 67 male, 44 female; diabetes duration 5.1 (2.5) years; HbA1c 7.4% (0.8) Retrospective before–after RWE MiniMed 670G CSII (77.5%) or MDI (22.5%) 111 Finland 12 months
Petrovski 2021 [42] Age 10.2 (2.6) [7–18] years; 15 male, 15 female; diabetes duration 2.8 (1.7) years; HbA1c 8.2% (1.4) Prospective before–after RWE MiniMed 670G MDI 30 Qatar 12 months
Ng 2024 [40] Age 12.3 (3.5) [2–19] years; 147 male, 104 female; diabetes duration 6.6 (3.7) years; HbA1c 7.9% (3.3) Prospective before–after RWE Control-IQ or MiniMed 780G or CamAPS FX CSII or MDI 251 England 12 months
Passanisi 2024 [41] Median age 12.9 [7–18] years; 192 male, 176 female; median diabetes duration 5.2 years; median HbA1c 7.3% Prospective before–after RWE MiniMed 780G CSII (66.6%) or MDI (33.4%) 368 Italy 12 months
Henry 2024 [33] Age range [10–25] years; NR diabetes duration NR; HbA1c 7.9% (IQR 7.7–8.0) Retrospective before–after RWE Control-IQ or MiniMed 780G CSII 48 France 12 months
Gruber 2024 [32] Median age 15.1 [IQR 12.9–17.0] years; 63 male, 40 female; diabetes duration 6.6 (4.0) years; HbA1c 8.65% (0.12) Prospective before–after RWE MiniMed 780G SAP 93 Israel 12 months
Rabbone 2025 [44] Age 7.9 (3.9) [1–18] years; 58 male, 26 female; diabetes duration NR; HbA1c 12% (2) Prospective before–after RWE MiniMed 780G or Tandem Control-IQ or MyLife Loop PLGS or MID 84 Italy 12 months
Ung 2025 [46] Age 21.0 (3.0) [15–25] years; 40 male, 61 female; diabetes duration 12 (5) years; HbA1c 9.6% (2.3) Retrospective before–after RWE MiniMed 780G or Tandemt: slimX2 or DBLG1 (Diabeloop) Before AID (not specified) 101 France 12 months
De Meulemeester 2025 [27] Age 12.0 (3.2) [6–18] years; 44 male, 70 female; diabetes duration 6.1 (3.6) years; HbA1c 7.8% (1.3) Prospective before–after RWE Control-IQ SAP 114 Belgium 12 months
Granados 2025 [31] Age 7.9 (3.7) [2–22] years; 92 male, 82 female; diabetes duration 5.3 (0.4) years; HbA1c 8.04% (1.7) Retrospective before–after RWE Omnipod 5 Before AID (not specified) 174 USA 12 months
Karges 2025 [34] Age 12.8 (3.9) [2–20] years; 7097 male, 6825 female; diabetes duration 6.2 (3.8) years; HbA1c 7.48% (1.1) Prospective before–after RWE AID (not specified) SAP 13,922 Multiple countries 18 months
Michaels 2024 [39] Age 18.8 [13–25] years; 8 male, 12 female; diabetes duration 9.7 (5.4) years; HbA1c 10.5% (2.1) Single-arm trial, ACTRN12621000556842 MiniMed 780G MDI 20 New Zealand 12 months
Schneidewind 2025 [45] Age 12.2 (3.8) [3.4–19.1] years; 60 male, 51 female; diabetes duration 6.1 (4.0) years; HbA1c 8.1% (1.1) Retrospective before–after RWE Control-IQ or MiniMed 780G or CamAPS FX SAP (32%) or CSII + CGM (44%) or MDI + CGM (23%) 111 Germany 24 months
Kiilavuori 2025 [35] Age 11.7 (3.4) [7–16] years; 52 male, 27 female; diabetes duration 6.4 (3.4) years; HbA1c 8.3% (1.0) Retrospective before–after RWE MiniMed 780G CSII (66%) or MDI (27%) or HCL (670G, 7%) 79 Finland 24 months
López-López 2024 [36] Age 2.4 (1.4) [1–6] years; 35 male, 26 female; diabetes duration NR; HbA1c 7.1% (0.8) Retrospective before–after RWE MiniMed 780G MDI 35 Spain 12 months
Franzone 202530 Age 4.4 (1.6) [1–6] years; 26 male, 15 female; diabetes duration 1.6 (1.4) years; HbA1c 7.5% (1.1) Retrospective before–after RWE Control-IQ or MiniMed 780G PLGS (68%) or MDI (22%) 41 Italy 12 months
Pulkkinen 2024 [43] Age 4.3 (1.3) [2–6] years; 18 male, 17 female; diabetes duration 2.3 (1.3) years; HbA1c 7.4% (0.7) Single-arm trial, NCT04949022 MiniMed 780G AID (37%) or SAP (54%) or MDI (9%) 35 Finland 18 months
Lührs 2025 [37] Median age 12.0 [IQR 9.3–14.7] years; 168 male, 137 female; diabetes duration 5.3 (IQR 2.7–8.3) years; HbA1c 7.4% (IQR 6.8–8.2) Retrospective before–after RWE Control-IQ or MiniMed 780G or MiniMed 670G PLGS (36%) or CSII (38%) or MDI (26%) 305 Germany 24 months
Criego 2024 [26] Age 10.4 (2.1) [6–13.9] years; 51 male, 59 female; diabetes duration 4.7 (2.6) years; HbA1c 7.7% (0.9) Single-arm trial (extension phase), NCT04196140 Omnipod 5 CSII (89%) or MDI (12%) 110 USA 24 months
DeSalvo 2024 [29] Age 4.7 (1.0) [2–6] years; 46 male, 34 female; diabetes duration 2.3 (1.1) years; HbA1c 7.4% (1.0) Single-arm trial (extension phase), NCT04476472 Omnipod 5 CSII (85%) or MDI (15%) 80 USA 15 months
Bismuth 2024 [25] Age 10.1 (1.7) [6.8–14] years; 70 male, 48 female; diabetes duration 5.2 (2.3) years; HbA1c 7.7% (0.7) Single-arm trial (extension phase), NCT04476472 Control-IQ CSII 118 France 24 months

HbA1c units reported as mean or median in % (SD or IQR). AID=automated insulin delivery. SAP=sensor augmented pump therapy. CSII=continuous subcutaneous insulin infusion. PLGS=predictive low glucose suspend. MDI=multiple daily injections. RWE=real-world evidence. RCT=randomised controlled trial. IQR=interquartile range. *Data are mean (SD) unless otherwise indicated

One study reported data for two age subgroups (10–17 years and 18–25 years), which were treated as two separate comparisons in our analysis [33]. Similarly, the study by Lührs et al. was split into comparisons evaluating different AID systems [37]. Another study compared AID against both PLGS therapy and MDI; we also split this into two comparisons (AID vs. PLGS and AID vs. MDI) [44]. Consequently, a total of 26 comparisons from 24 studies were included in the final meta-analysis.

The risk of bias assessment for the included studies is provided in the Supplementary Table S1-S2. Two RCTs were rated as low risk. Among the non-randomized studies, two were rated as high risk and the remainder as moderate risk.

Primary outcomes

Meta-analysis of 22 studies (yielding 25 independent comparisons) reporting TIR demonstrated that AID system use significantly increased time in the TIR compared to control treatments (Fig. 1), with a pooled MD of 11.56% (95% CI: 10.20 to 12.93; p < 0.001), equivalent to approximately 166 additional minutes per day (95% CI: 147 to 186 min). Substantial heterogeneity was observed among the studies (I² = 82%). For HbA1c, pooling of 21 studies (23 comparisons) demonstrated a significant reduction with AID use (MD: −0.52%; 95% CI: −0.63 to −0.40; p < 0.001; Fig. 2). Heterogeneity was also substantial (I² = 93%). Leave-one-out sensitivity analyses confirmed the robustness of both findings, with no single study driving the overall estimates (Figure S2 and S3).

Fig. 1.

Fig. 1

Forest plot for time in range (3.9–10 mmol/L)

Fig. 2.

Fig. 2

Forest plot for HbA1c

Secondary outcomes

Other glycemic outcomes are summarized in Table 2. Use of AID systems significantly increased TITR by a MD of 9.11% (95% CI 7.59 to 10.63; p < 0.001; Figure S4), with low heterogeneity (I²=33%). AID systems also significantly significantly reduced TBR1 by an MD of −0.69% (95% CI: −1.33 to −0.06; p = 0.032; Fig. 3), equivalent to approximately 10 fewer minutes per day (95% CI: 0.9 to 19 min). For hyperglycemia, AID use reduced TAR1 by an MD of −9.87% (95% CI: −11.56 to −8.17; p < 0.001; Figure S5), equivalent to approximately 142 fewer minutes per day (95% CI: 118 to 166 min).

Table 2.

Results of primary and secondary outcomes

Outcomes Comparisons MD (95% CI) P I2 P interaction
TIR (3.9–10.0 mmol/L)
All comparisons 25 11.56 (10.2 to 12.93) < 0.001 82%
Study design 0.386
RCT 2 14.67 (9.77 to 19.57) < 0.001 0
RWE 18 11.65 (9.89 to 13.41) < 0.001 85%
Single-arm trial 5 10.84 (8.47 to 13.21) < 0.001 81%
Type of AID 0.006
Control-IQ 3 12.86 (11.47 to 14.24) < 0.001 0
FlorenceM or CamAPS FX 2 8.54 (6.87 to 10.21) < 0.001 0
MiniMed 670G 2 11.57 (9.81 to 13.33) < 0.001 0
MiniMed 780G 5 12.38 (9.78 to 14.99) 71%
Omnipod 5 2 11.83 (8.4 to 15.26) 68%
Mixed or others 11 11.41 (8.43 to 14.38) < 0.001 90%
Study duration 0.290
< 12 months 20 12.08 (10.81 to 13.34) < 0.001 67%
≥24 months 5 9.96 (6.27 to 13.66) < 0.001 94%
Comparator 0.375
CSII or MDI 14 12.4 (11.72 to 13.09) < 0.001 0
SAP 5 12.04 (8.83 to 15.25) < 0.001 85%
Mixed or others 6 9.64 (5.08 to 14.2) < 0.001 93%
Age NA
≤ 7 years 6 9.07 (7.82 to 10.33) < 0.001 0
≤ 19 years 16 11.65 (10.59 to 12.7) < 0.001 53%
Mean HbA1c (%) 0.329
≥8.0% 6 13.74 (8.48 to 19.01) < 0.001 89%
<8.0% 19 11.04 (9.74 to 12.35) < 0.001 79%
HbA1c (%)
All comparisons 23 −0.52 (−0.63 to −0.4) < 0.001 93%
Study design 0.105
RCT 2 −0.76 (−1.1 to −0.41) < 0.001 0
RWE 16 −0.54 (−0.69 to −0.4) < 0.001 36%
Single-arm trial 5 −0.43 (−0.52 to −0.34) < 0.001 95%
Type of AID 0.521
Control-IQ 3 −0.6 (−0.75 to −0.45) < 0.001 50%
FlorenceM or CamAPS FX 2 −0.55 (−0.99 to −0.1) 0.016 54%
MiniMed 670G 3 −0.26 (−0.8 to 0.29) 0.352 94%
MiniMed 780G 4 −0.48 (−0.78 to −0.19) 0.001 91%
Omnipod 5 2 −0.46 (−0.58 to −0.34) < 0.001 0
Mixed or others 9 −0.66 (−0.91 to −0.4) < 0.001 94%
Study duration 0.013
< 12 months 17 −0.63 (−0.77 to −0.48) < 0.001 94%
≥24 months 6 −0.27 (−0.51 to −0.03) 0.029 93%
Comparator 0.791
CSII or MDI 11 −0.49 (−0.61 to −0.37) < 0.001 79%
SAP 5 −0.61 (−0.95 to −0.27) < 0.001 95%
Mixed or others 7 −0.5 (−0.87 to −0.12) 0.01 95%
Age NA
≤ 7 years 5 −0.41 (−0.6 to −0.23) < 0.001 74%
≤ 19 years 17 −0.49 (−0.59 to −0.39) < 0.001 77%
Mean HbA1c (%) < 0.001
≥8.0% 8 −0.92 (−1.18 to −0.66) < 0.001 79%
<8.0% 15 −0.35 (−0.47 to −0.24) < 0.001 93%
Secondary outcomes
TTIR (3.9–7.8 mmol/L) 8 9.11 (7.59 to 10.63) < 0.001 33%
TBR1 (< 3.9 mmol/L) 22 −0.69 (−1.33 to −0.06) 0.032 96%
TBR2 (< 3.0 mmol/L) 17 −0.31 (−0.54 to −0.08) 0.009 95%
TAR1 (> 10 mmol/L) 20 −9.87 (−11.56 to −8.17) < 0.001 77%
TAR2 (> 13.9 mmol/L) 15 −5.21 (−6.39 to −4.03) < 0.001 75%
Mean sensor glucose (mg/dL) 17 −15.05 (−17.99 to −12.11) < 0.001 84%
CV of glucose (%) 18 −0.99 (−1.76 to −0.21) 0.013 91%
SD of glucose (mg/d) 10 −5.80 (−7.00 to −4.59) < 0.001 62%

TAR=time above range. TBR=time below range. TIR=time in range. RWE=real-world evidence. RCT=randomised controlled trial. SAP=sensor augmented pump therapy. CSII=continuous subcutaneous insulin infusion. MDI=multiple daily insulin injection. MD=mean difference. CV=coefficient of variation (%). SD=standard deviation. TTIR=time in tight range

Fig. 3.

Fig. 3

Forest plot for time below range (< 3.9 mmol/L)

AID systems reduced TBR2 by an MD of −0.31% (95% CI: −0.54 to −0.08; p = 0.009; Figure S6) and TAR2 by an MD of −5.21% (95% CI: −6.39 to −4.03; p < 0.001; Figure S7). AID systems were also associated with a significant reduction in mean sensor glucose (MD: −15.05 mg/dL; 95% CI: −17.99 to −12.11; p < 0.001; Figure S8). Additionally, AID systems significantly improved glycemic variability parameters, with a reduction in glucose CV by 0.99% (95% CI −1.76 to −0.21; p = 0.013; Figure S9) and glucose SD by 5.80 mg/dL (95% CI −7.00 to −4.59; p < 0.001; Figure S10).

Subgroup analyses

Subgroup analyses for TIR and HbA1c (25 comparisons) were performed to explore potential sources of heterogeneity (Table 2). The improvement in TIR was consistent across most subgroups, including study design (RCT, RWE, or single-arm trial), type of AID system (MiniMed 780G, Control-IQ, MiniMed 670G, Omnipod 5, CamAPS FX, and mixed or others), study duration (≥ 24 months or < 24 months), type of comparator (CSII or MDI, SAP, and mixed or others), age (≤ 7 years or ≤ 19 years), and mean baseline HbA1c (≥ 8.0% or < 8.0%).

For HbA1c, subgroup analyses revealed significant interactions for study duration (pinteraction= 0.013) and baseline HbA1c level (pinteraction< 0.001). The reduction in HbA1c seemed to be greater in studies of shorter duration (< 24 months: MD −0.63% vs. ≥24 months: MD −0.27%) and in those enrolling participants with higher baseline HbA1c (≥ 8.0%: MD −0.92% vs. <8.0%: MD −0.35%).

Publication bias

For the primary outcomes, visual inspection of funnel plots and Egger’s test indicated no significant publication bias for TIR (Figure S11; p = 0.453). However, significant publication bias was detected for HbA1c (Figure S12; p < 0.001). Among the secondary outcomes, statistically significant publication bias was suggested for mean sensor glucose (Figure S13; p = 0.038), but not for the other metrics (Figure S14-S20).

Discussion

This systematic review and meta-analysis of 26 studies demonstrates that AID systems significantly improve long-term glycemic outcomes in young people with T1D. The use of AID systems was associated with an 11.56% increase in TIR, equivalent to approximately 166 additional minutes per day, and a clinically meaningful 0.52% reduction in HbA1c, while simultaneously reducing time in hypoglycemia and hyperglycemia. The demonstration of significant benefit for both key metrics in the overall analysis and across most predefined subgroups underscores the robustness of these findings.

Our findings extend the evidence from previous meta-analyses that primarily focused on short-term outcomes [1012]. The magnitude of TIR improvement observed in our study is remarkably consistent with previous reports in children and adolescents [12, 13], suggesting that the glycemic benefits of AID systems are not only substantial but also sustainable over extended periods. This consistency across different study durations strengthens the clinical validity of AID technology for long-term diabetes management in young people.

The glycemic outcomes demonstrated a high degree of consistency between clinical trials and RWE studies, indicating that the efficacy observed in clinical trial settings translates effectively to routine clinical practice. Similarly, the HbA1c reduction was consistent across different study designs and patient populations. This convergence of evidence from different study designs provides robust support for the effectiveness of AID systems in diverse clinical settings.

The glycemic benefits observed in our analysis are particularly relevant for youth with elevated baseline HbA1c. While our study did not specifically focus on this population, evidence from targeted studies suggests that AID systems offer substantial benefits to individuals with elevated HbA1c levels [39, 50]. These findings align with our subgroup analysis showing greater HbA1c reductions in youth with higher baseline HbA1c, indicating that AID systems may be particularly effective in higher-risk populations who have the most room for improvement. This supports prioritizing AID system access for youth with elevated baseline HbA1c to improve long-term outcomes.

The safety profile of AID systems requires careful consideration in the future. While two RCTs showed no significant difference in severe hypoglycemia or diabetic ketoacidosis (DKA) rates between AID and conventional therapy [38, 49], data from a large cohort study indicated a potentially increased risk of diabetic ketoacidosis with closed-loop therapy [34]. This finding underscores the importance of ongoing education and monitoring, particularly during the transition to AID systems. However, the overall benefits in glycemic control were maintained across both study designs. Future research to reduce DKA risk in AID users may include integrating ketone sensors into AID systems, developing algorithmic alerts for prolonged hyperglycemia unresponsive to AID, and establishing standardized sick-day management protocols with targeted user education on pump disconnection and illness-related risks.

Several limitations should be acknowledged. First, substantial heterogeneity was observed for the primary outcomes, which may be attributable to differences in study design, patient characteristics, AID systems, comparator treatments, and study duration across studies. Second, all real-world studies were uncontrolled before-after designs, which are susceptible to confounding. Third, the generalizability of findings to low-income countries may be limited, as nearly all of the included studies were conducted in high-income countries. Finally, the long-term cost-effectiveness of AID systems requires further evaluation.

Our findings that various AID systems produced comparable long-term glycemic benefits are supported by a recent network meta-analysis, which found that hybrid, advanced hybrid, and full closed-loop systems all significantly improved TIR compared to conventional insulin therapy [51]. This consistency across system types suggests that the core closed-loop principle, rather than a specific algorithm, is the key driver of glycemic improvement, reassuring clinicians that the clinical benefits of AID technology are robust across different commercial systems.

The long-term clinical benefits demonstrated in our analysis must be considered alongside economic implications for widespread AID implementation. Recent cost-effectiveness analyses specifically focused on pediatric populations provide compelling evidence. In Australia, HCL therapy showed favorable cost-effectiveness with an incremental cost-effectiveness ratio of AUD $32,789 per QALY gained [52]. Similarly, Swedish analyses found the Control-IQ system to be a dominant strategy compared with multiple daily injections or conventional pump therapy across all time horizons [53]. Most notably, a binational trial of the Cambridge hybrid closed-loop system projected cost-effectiveness below the £20,000/QALY threshold in the UK and potential cost savings in the US setting [54]. These consistent findings across different healthcare systems and AID technologies suggest that the improved glycemic control observed in our meta-analysis may translate into economically efficient long-term outcomes for pediatric populations. While initial acquisition costs remain substantial, the converging evidence indicates that AID systems represent good value for money in youth with T1D through prevention of complications and improved quality of life.

Conclusions

This comprehensive systematic review and meta-analysis provides robust evidence that AID systems maintain significant glycemic benefits for young people with T1D in the long-term. The consistent outcomes observed across clinical trials and RWE studies support the long-term use of AID technology in diabetes management for young people.

Supplementary Information

Author contributions

B.Z. and D.L. conceived and designed the study. Z.S., and S.Y. undertook the literature review and extracted the data. B.Z., S.Y., and L.G. coded the statistical analysis, figures, and appendix. Z.S., B.Z., and L.G. interpreted the data and wrote the first draft of the manuscript. All authors reviewed and revised subsequent drafts and approved the final version. B.Z. is the guarantor of this work and, as such, had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Funding

This work was supported by the Tianjin Key Medical Discipline Construction Project (TJYXZDXK-3-003D) and National Key Clinical Specialty Construction Project for Emergency Medicine (No. 2023283).

Data availability

The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Declarations

Ethics approval and consent to participate

Not applicable.

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.

Footnotes

Publisher’s note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Zhihui Sun and Sihan Yang served as co-first authors.

Contributor Information

Le Gao, Email: gaole0513@connect.hku.hk.

Lin Dou, Email: doulint@163.com.

Baoqi Zeng, Email: zengbaoqi@126.com.

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Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Supplementary Materials

Data Availability Statement

The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.


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