Glucose and free fatty acid turnover in Cushing's syndrome.

Glucocorticoids are known to have acute effects on glucose and free fatty acid (FFA) metabolism. The effects of the longstanding hypercorticism of Cushing's syndrome were studied by isotopic techniques in a group of Cushingoid patients compared to a control group. In the Cushing's group, glucose production and utilization rates were significantly higher than in control subjects, while FFA turnover also tended to be higher, but not significantly. It is suggested that increased glucose production is the main cause of the hyperglycemia seen in Cushing's syndrome.