Effects of Various Salts on Carbohydrate Metabolism and Blood Pressure in Diabetic Children

Abstract

The excessive loss of minerals from the body in diabetic acidosis has recently been presented quantitatively in detailed balance studies by Peters 1 and Atchley 2 and their co-workers. Kydd 3 has emphasized the depletion of chloride in excess of other electrolytes, as if the base lost with the ketone acids might be derived from NaCl rather than from bicarbonate. He stresses the need for replacement of chloride during recovery from coma. Diabetic children not infrequently manifest an unusual craving for salt, even when not excreting ketone bodies in abnormal amounts. This has been interpreted by Joslin as most likely being due to the high potassium content of their vegetable diets.

The present study was suggested by our experience in the case of a 15-year-old boy, who, as he emerged from diabetic coma, begged for salt and voraciously consumed 80 gm. of NaCl in the course of 24 hours. The water intake was proportionately increased. When it was observed that the craving for salt did not abate long after the disappearance of ketosis and that the patient continued to take 60 gm. daily before being satisfied, he was placed in the metabolism ward where complete balance studies could be carried out under standard conditions. He was given a constant diet containing protein 16, fat 33, carbohydrate 42, and water 1200 gm. every 6 hours.

This was made up from powdered milk, bread, butter, eggs, cane sugar, lemon juice and a small amount of powdered yeast. The insulin dosage was kept constant for each period, totaling 32 units per day. This dosage of insulin permitted the occurrence of glycosuria in every 6-hour period, thus making comparative measurements possible.

Shortly after the study was undertaken, it was discovered (1) that the high NaCl intake was accompanied by an elevation of arterial blood pressure from an average of 110 mm. of mercury systolic and 80 diastolic to 175 systolic and 115 diastolic and (2) that the urinary excretion of glucose fell from a control level of between 60 and 70 gm. to between 10 and 20 gm. daily under the same conditions. Reduction of the NaCl intake to the control value of about 4 gm. daily caused a return of the glucose excretion to the original level and a fall in the blood pressure to normal.