Young Children Have Higher Variability of Insulin Requirements: Observations During Hybrid Closed-Loop Insulin Delivery

Abstract

To quantify age-related variability of insulin needs during day and night closed-loop insulin delivery. RESEARCH DESIGN AND METHODS We retrospectively analyzed data from hybrid closed-loop studies involving young children (1-6 years old, n 5 20), children (7-12 years, n 5 21), adolescents (13-17 years, n 5 15), and adults (>18 years, n 5 58) with type 1 diabetes. The coefficient of variation quantified variability of insulin needs during 3 weeks of unrestrictedliving hybrid closed-loop use. RESULTS Data from 2,365 nights and 2,367 days in 114 participants were analyzed. The coefficient of variation of insulin delivery was higher in young children compared with adults (mean difference at nighttime 10.7 percentage points [95% CI 2.9-18.4], P 5 0.003; daytime 6.4 percentage points [95% CI 2.0-10.9], P 5 0.002) and compared with adolescents (mean difference at nighttime 10.2 percentage points [95% CI 0.0-20.4], P 5 0.049; daytime 7.0 percentage points [95% CI 1.1-12.8], P 5 0.014). CONCLUSIONS Diabetes management in young children is complicated by higher variability in insulin requirements, supporting fast-track clinical practice adoption of closed-loop in this vulnerable population. With increasing application of insulin pump therapy and continuous glucose monitors, hybrid closed-loop has become a feasible treatment modality for people with type 1 diabetes (1,2). Apart from manual mealtime boluses, insulin delivery is autonomously modulated by a control algorithm based on real-time sensor glucose values. Insulin delivery may vary considerably from day to day and night to night due to varying activity levels, insulin set-changes, meal timings and composition, and other factors (3,4). To date, the association between age and insulin variability has not been assessed. In the present analysis, we investigate whether insulin requirements may be more variable in younger age.

Benefits and Challenges of Current Closed-Loop Technologies in Children and Young People With Type 1 Diabetes

“…Type 1 diabetes is challenging to manage at any age, but management is further complicated in young children under the age of 7 by a variety of unique physiological, behavioral and developmental factors. Young children have higher variability in insulin requirements and higher insulin sensitivity than older children and adults (34), as well as more unpredictable eating and activity patterns. Furthermore, hypoglycaemia is frequently asymptomatic and can be prolonged, particularly at night-time (35,36).…”

“…In a 3-week closedloop study in 24 very young children, time in the target range 3.9-10.0 mmol/L was highest overnight with reduction in hypoglycaemia compared to daytime (31) (Table 1). Variability in insulin requirements in young children is highest overnight (34), and closed-loop systems are uniquely positioned to address this by delivering insulin in a glucose-responsive manner. Qualitative data shows that parents noted improvements in quality of sleep with closed-loop, both for themselves and their child (37,38).…”

Time in range centered diabetes care

“…Optimal diabetes management should be multidisciplinary and tailored for each person with diabetes (PWD), and is dependent on regular glucose monitoring, precise insulin dosing, and rational decisionmaking support. However, everyday diabetes care is complicated by the variability in insulin requirements for each PWD as insulin dose needed to maintain normoglycemia fluctuates from one day (or night) to another, and might be, especially in children and adolescents, challenging to achieve with conventional treatment modalities (6,7).…”

Add‐on therapy with dapagliflozin under full closed loop control improves time in range in adolescents and young adults with type 1 diabetes: The DAPADream study

“…Variability of insulin delivery is age‐dependent, providing an additional challenge in the young age group, even with AID 27 . Indeed, clinical trials of automated insulin delivery in the very young have been shown to decrease parental burden 28 .…”