Type 1 diabetes in the youngest: from distinct needs to new frontiers in care

Type 1 diabetes (T1D) in very young children poses unique clinical and psychosocial challenges due to distinct physiological, developmental, and behavioural characteristics of this age group. Advances in diabetes technology, particularly hybrid closed-loop (HCL) systems, are transforming T1D management in young children by integrating continuous glucose monitoring (CGM) with automated insulin delivery (AID). Evidence from randomized controlled trials and real-world studies consistently demonstrates that HCL systems improve time in range, lower HbA1c, and reduce glycaemic variability without increasing the risk of severe hypoglycaemia or diabetic ketoacidosis. Benefits are especially evident overnight, when glycaemic control is more stable, although daytime management remains more complex, due to unpredictable behaviours typical of preschoolers and marked circadian variability in insulin needs. Accordingly, the use of HCL fail to decrease hypoglycaemia in this population. Additional strategies, such as insulin dilution, may facilitate safer delivery of small doses, reducing the risk of nocturnal hypoglycaemia and improving time in range (TIR). Beyond metabolic outcomes, HCL systems substantially improve quality of life for both children and caregivers, reducing fear of hypoglycaemia, easing parental burden, and improving sleep and emotional well-being. Overall, current evidence supports HCL as a safe and effective therapeutic option for very young children with T1D, offering significant metabolic and psychosocial benefits, without completely eliminating the risk of hypoglycaemia. These findings highlight the need for further refinement of age-specific algorithms capable of addressing the unique physiological variability of this population.