Patient Sample and Characteristics

The EQOL study included 290 participants in the run-in phase, of whom 286 entered the study phase (Fig. 2). Four patients participating in the run-in phase withdrew from the study because they found the pump uncomfortable (n = 1), did not feel comfortable to rely on auto mode (n = 1), or considered sensor installation and uploads as too tedious (n = 2). The ITT population at 6 months and at 12 months consisted of 270 and 256 participants, respectively.

Fig. 2

Patient disposition flowchart

On average, participants were 39 years (± 6.3) old, and 55.2% were female (Table 1). Mean diabetes duration was 21 (± 12.7) years. Sixty percent had received pump combined with intermittently scanned CGM before, compared with 10.7% and 20.3% receiving real-time CGM and pump-only treatment, respectively. Mean HbA1c at baseline was 7.76% (± 0.818).

Table 1 Demographic and clinical baseline data for patients entering the run-in phase (n = 290)Efficacy EndpointsChanges in TIR

The absolute change in TIR at 6 months was estimated at a mean 11.8 percentage points (SD 8.96, 95% CI 10.7–12.9, p < 0.0001), from 61.9% (SD 11.0) TIR with Manual mode to 73.7% (SD 7.4) TIR with Auto mode. This change was equivalent to an additional 2.8 h per day spent in range during the study phase (Fig. 3). This result was found to be robust in sensitivity analyses restricted to participants with ≥ 10 days of sensor wear during the run-in phase, in whom TIR changed from 62.0% (SD 10.8) to 73.7% (SD 7.4), for a mean absolute change of 11.8 percentage points (SD 8.7, 95% CI 10.7 to 12.9, p < 0.0001), and was observed in both pediatric and adult participants.

Fig. 3

Changes at 6 and 12 months from baseline in glycemic categories. Abbreviations: Δ difference, CI confidence interval, dL deciliter, L liter, mg milligram. *p < 0.0001

At 6 and 12 months during the study phase, participants spent statistically significantly less time in hypo- and hyperglycemic ranges (p < 0.0001, Fig. 3). In particular, participants spent approximately 10% less time in hyperglycemic states, i.e., with SG values > 180 mg/dL. Improvements in glycemic control were larger during the night, with 78.3% (SD 10.72) and 78.5% (SD 10.146) of time spent in range at 6 and 12 months, respectively, versus 60.8% (SD 14.95) in the run-in phase, than during the day, with 72.1% (SD 7.95) and 71.6% (SD 8.01) of time spent in range at 6 and 12 months, respectively, versus 62.2% (SD 11.15) in the run-in phase (Fig. S1 in the Supplementary Material).

Changes in Other Glycemic Parameters

Sustained improvements were noted for all observed glycemic parameters during the study relative to the run-in phase (Table S1 in the Supplementary Material). Statistically significant (all p < 0.0001) reductions of 0.52% (95% CI 0.40–0.60%) and 0.42% (95% CI 0.30–0.50%) were observed in HbA1c at 6 and 12 months, respectively, relative to the mean 7.76% observed during the run-in period. Similarly, the GMI was reduced by 0.28% (95% CI 0.24–0.33%) at 6 months and by 0.27% (95% CI 0.24–0.30%) at 12 months relative to the run-in phase mean. Mean sensor glucose values decreased by 11.9 mg/dL (95% CI 10.2–13.6 mg/dL) at 6 months and by 11.3 mg/dL (95% CI 9.90–12.7 mg/dL) at 12 months. Glucose variability also improved as the SD decreased by 6.78 mg/dL (95% CI 5.84–7.71 mg/dL) at 6 months and 6.19 mg/dL (95% CI 5.42–6.97 mg/dL) at 12 months, while the coefficient of variation decreased by 1.76% (95% CI 1.21–2.31%) at 6 months and 1.53% (95% CI 1.09–1.97%) at 12 months (all differences: p < 0.0001).

Reaching Glycemic Targets

When using Auto mode during the study phase, participants more often reached glycemic targets (Fig. S2 in the Supplementary Material). Specifically, 31.7% of participants had an HbA1c < 7.0% at 12 months, compared with only 14.9% of participants during the run-in phase. The percentage of patients with TIR > 70% more than tripled from the run-in phase (21.2%) to 12 months (66.7%).

Changes in Hypoglycemia

Both biochemical and severe hypoglycemic event incidence improved. During the run-in phase, a mean 1.86 (± 2.21) biochemical hypoglycemic events occurred per patient and week. At 6 and 12 months, the mean number of events had decreased to 1.08 (± 1.31) and 1.07 (± 1.24), respectively. Regarding SHEs, 12 participants (4.1%) reported a total of 34 events in the year before enrollment. In contrast, using Auto mode, only four participants (1.5%) reported a total of six events at 6 months. At 12 months, no SHEs were reported.

QoL EndpointsTreatment Satisfaction

Treatment satisfaction improved with Auto mode in adults, teens, and children/parents, with DTSQc values of + 13.1 (± 5.3, p < 0.0001) in adults, + 18.3 (± 12.3, p < 0.0001) in teens, and + 29.6 (± 4.9, p = 0.0002) in children/parents. DTSQs values were also higher at 6 months for adults (+ 4.3 [95% CI 3.0–6.0], p < 0.0001) and children/parents (+ 6.3 [95% CI 2.0–15.0], p = 0.0081), but not teens. At 12 months, DTSQs values were numerically and statistically significantly higher than during the run-in phase in all groups (Fig. 4a–c).

Fig. 4

a–e Treatment satisfaction, quality of life, and fear of hypoglycemia trajectories. Abbreviations: DQoL Diabetes Quality of Life (instrument), DTSQs Diabetes Treatment Satisfaction Questionnaire status, HFS Hypoglycemia Fear Survey

QoL

QoL, measured using the DQoL in adults and teens, also improved, although the differences versus baseline were statistically significant only in adults (Fig. 4d).

Fear of Hypoglycemia

Relative to the run-in phase, fear of hypoglycemia decreased at both follow-up visits in all groups (Fig. 4e). The decreases were largest, and statistically significant, in adults, who also scored the highest on the HFS during the run-in phase. Children/parents scored lower than adults, with the reductions in their HFS scores also reaching statistical significance. In contrast, teens reported the least fear of hypoglycemia during the run-in phase, and changes over time were numerically small and failed to reach statistical significance.

System Usage/Device Settings

In the EQOL study, most participants used the available technology consistently. During the run-in phase, pump wear was 97%, while it was 95% and 96% at 6 and 12 months, respectively. The corresponding values for sensor wear were 92%, 90%, and 90%, respectively. At 6 months, 91% of time was spent in Auto mode, which increased to 93% at 12 months.

Optimal Settings Usage

Optimal settings were used 25–33% of the time at 6 and 12 months (Table 2). For both glycemic markers (SG values and GMI) as well as time spent below, in, and above range, optimal settings were generally associated with the most preferable outcomes at 6 months (Fig. S3 in the Supplementary Material).

Table 2 Device settings across the study period

In participants with optimal settings, mean SG was 138.2 mg/dL, GMI was 6.6%, and time spent < 54 mg/dL was 0.9%, compared with a mean SG of 155.5 mg/dL, GMI of 7.0%, and time spent < 54 mg/dL of 0.6% in participants with a glucose target of 120 mg/dL and AIT of 2–3 h.