Predicting Factors Associated with Hypoglycemia Reduction with Automated Predictive Insulin Suspension in Patients at High Risk of Severe Hypoglycemia: An Analysis from the SMILE Randomized Trial.

Background: This analysis from the SMILE randomized study was performed to identify predictive factors associated with the greatest reductions in hypoglycemia with the Medtronic MiniMed™ 640G Suspend before low feature in adults with type 1 diabetes at high risk of severe hypoglycemia. Methods: Clinical and treatment-related factors associated with decreased sensor hypoglycemia (SH) were identified in participants from the intervention arm by univariate and multivariate analyses. Results: The reduction in SH events <54 mg/dL (<3.0 mmol/L) in the intervention group was significantly (P < 0.0001) associated with the baseline mean number of sensor hypoglycemic events (MNSHE) <54 mg/dL. When excluding continuous glucose monitoring (CGM) factors not readily available (MNSHE, duration of SH events, area under the curve, mean amplitude of glycemic excursions), only the baseline mean time spent <54 mg/dL was found to be a significant independent predictor factor (P < 0.0001). Baseline HbA1c, mean self-monitoring of blood glucose (SMBG), and coefficient of variation of SMBG were significant, although weak, predictors in the absence of any CGM data. Conclusions: The greatest reductions in SH events achieved with the MiniMed 640G system with the Suspend before low feature were seen in participants with higher baseline MNSHE. Measuring these (usually uncollected) events can be a useful tool to predict hypoglycemia reduction. ClinicalTrials.gov Registration Identifier NCT02733991.

Efficacy and safety of suspend-before-low insulin pump technology in hypoglycaemia-prone adults with type 1 diabetes (SMILE): an open-label randomised controlled trial.

BACKGROUND: Hypoglycaemia unawareness and severe hypoglycaemia can increase fear of hypoglycaemia and the risk of subsequent hypoglycaemic events. We aimed to assess the safety and efficacy of insulin pump therapy with integrated continuous glucose monitoring (CGM) and a suspend-before-low feature (Medtronic MiniMed 640G with SmartGuard) in hypoglycaemia-prone adults with type 1 diabetes. METHODS: SMILE was an open-label randomised controlled trial done in people aged 24-75 years with type 1 diabetes for 10 years or longer, HbA1c values of 5·8-10·0% (40-86 mmol/mol), and at high risk of hypoglycaemia (recent severe hypoglycaemia or hypoglycaemia unawareness defined by a Clarke or Gold score ≥4). Participants were enrolled from 16 centres (eg, clinics, hospitals, or university medical centres) in Canada, France, Italy, the Netherlands, and the UK. After baseline run-in phase (2 weeks), participants were randomly assigned to the MiniMed 640G pump (continuous subcutaneous insulin infusion) with self-monitoring of blood glucose (control group) or to the MiniMed 640G system with the suspend-before-low feature enabled (intervention group), for 6 months. The study statistician analysing the data was masked to group assignment until final database lock; because of the nature of the intervention, participants and treating clinicians could not be masked to group assignment. The primary outcome was the mean number of sensor hypoglycaemic events, defined as 55 mg/dL (3·1 mmol/L) or lower, and was analysed on an intention-to-treat basis in all randomly assigned participants. This trial is registered with ClinicalTrials.gov, number NCT02733991, and is completed. FINDINGS: Between Dec 7, 2016, and March 27, 2018, 153 participants with a mean age 48·2 [12·4] years were randomly assigned: 77 to the control group (mean age 47·4 [12·5] years) and 76 to the intervention group (mean age 49·0 [12·2] years). After 6 months, the intervention group had significantly fewer hypoglycaemic events per participant per week (1·1 [SD 1·2] vs 4·1 [3·4] mean events, model-based treatment effect -2·9 [95% CI -3·5 to -2·3]; p<0·0001) and fewer severe hypoglycaemic events (instances requiring third-party assistance with carbohydrate or glucagon administration, or other resuscitative actions) overall (three vs 18; p=0·0036). The most common adverse events were hypoglycaemia (observed in ten [13%] of 77 participants in the control group vs four [5%] of 76 in the intervention group) and hyperglycaemia (observed in seven [9%] of 77 vs seven [9%] of 76). No serious adverse device effects or episodes of diabetic ketoacidosis were reported. INTERPRETATION: Insulin pump therapy with integrated CGM and a suspend-before-low feature reduced the frequency of sensor hypoglycaemic and severe hypoglycaemic events in hypoglycaemia-prone adults compared with use of continuous subcutaneous insulin infusion without real-time CGM. These results suggest that this technology could be beneficial in this high-risk population. FUNDING: Medtronic International Trading Sàrl and Medtronic Canada.