In patients with FRDA, hyperglycemia generally develops at an average of 15 years after the onset of neurologic symptoms. Diabetes onset is often acute and ketosis-prone; appropriate management includes insulin at diagnosis. Past research has shown that often, the first presentation of diabetes in FRDA is ketoacidosis. In any given patient, diabetes may result from defects in insulin secretion by the pancreatic β-cells, impaired insulin action, or both. In FRDA, both insulin deficiency and insulin resistance have been reported.
Because metformin inhibits complex I of the mitochondrial respiratory chain, it should be used with caution. Exogenous insulin administration is often the best choice of treatment for FRDA patients. Regular screening for onset of diabetes as well as early initiation of insulin therapy should be part of overall management of FRDA.
