Urine concentration in depressive illness.

A total of 132 urine specimens were obtained from 17 depressed patients and 18 controls under conditions of mild water deprivation. Mean values of milliosmoles of solute and millilitres of urine excreted per hour were obtained for each subject. The depressed patients excreted significantly less solute than the control group per unit volume of urine. There was no significant difference between the solute excretion rates of depressed patients and those who had recently recovered from depression-though the trend was towards normality. The significance of these results is discussed in relation to studies on body fluids and electrolytes and the role of ADH and aldosterone in affective disorders.