P.365 - Glycemic control during fasting in patients with low skeletal muscle mass

Patients with low skeletal muscle mass have shown to react differently to fasting than expected. An earlier study of the glucose metabolism in adults with Spinal muscular atrophy (SMA) and congenital myopathies among others found that especially the patients with low skeletal muscle mass became hypoglycemic after a period of fasting and the same has been described in cases with children with low muscle mass admitted after febrile episodes and fasting. This indicates that further research into the glycemic control of persons with low muscle mass is warranted. The aim of the study is to investigate the carbohydrate and fatty acid oxidation in patients with low muscle mass. Furthermore, the study will investigate the metabolic differences in children and adults with the same diagnosis. These systemic metabolic pathways have never been described in these patient groups before. Fat and carbohydrate metabolism will be measured using metabolic tracers (stable isotopes) combined with indirect calorimetry from measures of oxygen consumption (VO2) and carbon dioxide production (VCO2). The study will focus on adult patients diagnosed with SMA types II and III and paediatric patients diagnosed with SMA type II and congenital muscular dystrophies with mutations in the LAMA2 gene. The primary outcome measure will be registering development of hypoglycaemia during fasting. Secondary outcome measures are changes in fat and carbohydrates metabolisms from fed to fasted state and changes in hormones and metabolites during fasting. Data from the children will be compared to data from WHO and literature on healthy children and their overall energy utilization using the Schofield equation. Data from the adult patients will be compared to a group of matched untrained healthy control subjects for comparison of the primary and secondary outcome measures. The research trials will be conducted in late spring and summer and preliminary data will be available for presentation at the WMS meeting.