Daytime liver glycogen accumulation measured by C-13 magnetic resonance spectroscopy in young children with type 1 diabetes mellitus

AIM: To examine daytime liver glycogen accumulation in prepubertal children with Type 1 diabetes mellitus (Type 1 DM) compared with non-diabetic controls. METHODS: Liver glycogen content was ascertained in the fasting (morning) and fed (afternoon) state using 13C magnetic resonance (MR) spectroscopy. Data were analysed from six children with Type 1 DM (median (range) age 8.7 (6.3-12.2) years), who were all on conventional insulin regimens, and six healthy controls (age 8.9 (7-10.2) years). RESULTS: Children with diabetes tended to have lower fasting glycogen values than controls but this did not reach statistical significance (median (range) 154 (70-177) vs. 178 (120-203) mM glycosyl units, Type 1 DM vs. controls respectively; P = 0.06). Glycogen increased in all children with diabetes during the day and concentrations were similar to those in controls by the afternoon (175 (157-299) vs. 172 (136-238) mM glycosyl units; P = 0.7). CONCLUSIONS: The ability of young children with Type 1 DM to replace liver glycogen depleted after an overnight fast was at least as good as that in control subjects, suggesting that impaired glycogen storage is not a contributory factor in nocturnal hypoglycaemia.