Determinants of rhabdomyolysis in the diabetic state.

To evaluate the determinants of rhabdomyolysis in the diabetic state, we compared biochemical and clinical features of diabetic patients with (group 1, 41 patients) and without (group 2, 36 patients) rhabdomyolysis. There was no difference in values for serum potassium, bicarbonate, phosphate and calcium between the two groups. Nineteen patients in group 2 and 21 patients in group 1 were hypokalemic. The mean serum sodium level was higher (p less than 0.001) in group 1 patients (148.8 +/- 2.1 mEq/l) than in group 2 patients (135.0 +/- 1.1 mEq/l). Only 1 patient was hypernatremic in group 2, whereas 24 patients had hypernatremia in group 1. Linear regression of the creatine phosphokinase values versus serum sodium levels suggested a high correlation (p less than 0.001). The mean blood glucose level was higher (p less than 0.05) in group 1 patients (640.8 +/- 80.3 mg/dl) when compared to group 2 patients (436.0 +/- 56.7 mg/dl). There was a linear association (p less than 0.05) between the levels of blood glucose and creatine phosphokinase values in the patients with rhabdomyolysis. The mean serum osmolality was 350.3 +/- 8.2 mosm/kg in group 1 patients as compared to 304.9 +/- 3.6 mosm/kg in group 2 patients (p less than 0.001). There was also a significant correlation (p less than 0.001) between the serum osmolality levels and the serum creatine phosphokinase values in group 1 patients. We conclude that serum sodium, serum osmolality and blood glucose are major determinants for the occurrence of rhabdomyolysis in the diabetic state.