Effects of student examination stress on the blood and urine osmolality: a possible syndrome of inappropriate ADH [SIADH]

Serum Na[+], K[+], glucose, urea, osmolality, urine Na and osmolality were measured in university students subjected to examination stress. A total of 16 healthy subjects of the age range 19-23 were studied. The results showed significant decrease in serum osmolality attributed mainly to hyponatremia together with significant increase in urine Na[+] and osmolality. These results suggest an inappropriate secretion of antidiuretic hormone [ADH] as a result of emotional stress acting on the visceral brain [limbic and reticular activating systems]