Patients with severe muscle wasting are prone to develop hypoglycemia during fasting.

The authors investigated whether hypoglycemia develops during 23 hours of fasting in patients with Duchenne dystrophy (7 patients), spinal muscular atrophy (4 patients), and congenital myopathy (2 patients), all with residual muscle mass <10% of body weight. All patients with spinal muscular atrophy and congenital myopathy and one patient with Duchenne dystrophy, but none of six healthy subjects, developed hypoglycemia. Skeletal muscle is an important source of gluconeogenic substrates during fasting. Hypoglycemia must be considered in patients with low muscle mass, especially during surgery and febrile episodes.