Pediatr Diabetes. 2018 Apr 19. doi: 10.1111/pedi.12683.
According to these authors, earlier studies had shown that children with type 1 diabetes mellitus (T1D) experience mild cognitive alterations compared to healthy age-matched controls. This might develop during the course of the disease and relate to both hypo- and hyperglycemia. Another explanation points to psychosocial factors or common underlying yet unknown alterations of the central nervous system. The neural basis of these cognitive differences is unclear, but may be due in part to the effects of dysglycemia on developing neurons.
This study examined longitudinal changes in hippocampus volume using structural magnetic resonance imaging in 142 young children with T1D and 65 age-matched controls (410 years old) at two time points, 18 months apart.
Longitudinal hippocampus growth did not differ between children with T1D and healthy controls, however, among T1D children slower hippocampus growth was associated with both greater exposure to hyperglycemia (higher HbA1c) and greater glycemic variability. These observations indicate that the current practice of tolerating some hyperglycemia to minimize the risk of hypoglycemia in young children with T1D may be sub-optimal for the developing brain. Efforts that continue to assess the factors that influence neural and cognitive development in children with T1D are critical in minimizing the deleterious effects of diabetes.
Importantly, this study indeed indicates that, in addition to the deleterious effects of hypoglycemia on the developing brain, hyperglycaemia might also impair central nervous system development, cognitive development and learning capacity in children with diabetes. It has to be stressed that both hyper- and hypoglycemia need to be avoided and optimal metabolic control is to be obtained at all ages in children with T1D.