In a recent issue of the ARCHIVES, Oster and Singer1 use the correction factor described by Katz2 to correct hyponatremia caused by hyperglycemia. According to this correction factor, the serum sodium level decreases by 1.6 mmol/L for each 5.6-mmol/L (100-mg/dl) increase in glucose load; therefore, 1.6 mmol is added to the reported sodium value for every 5.6 mmol of glucose over 5.6 mmol/L. No controlled experimental data are available to support the use of Katz's correction factor.
Kashyap AS. Hyperglycemia-Induced Hyponatremia: Is It Time to Correct the Correction Factor?. Arch Intern Med. 1999;159(22):2745. doi: