Electrodermal activity in relation to cortisol dysregulation in depressive patients.

Electrodermal activity (EDA), basal morning plasma cortisol, outcome of the dexamethasone suppression test (DST), and nocturnal urinary cortisol excretion were studied in a somewhat confined number of originally 59 depressive patients and 59 matched healthy subjects. The patients showed nocturnal hypercortisolism. According to the DST, EDA and cortisol dysregulation were unrelated. In the total patient group, the correlations between EDA and cortisol in plasma and in urine were small and insignificant. However, in suicide attempters, in nonsuicidal patients, and in the healthy subjects, complex patterns of correlations were found between tonic electrodermal activity, electrodermal responsivity, basal morning plasma cortisol, and nocturnal urinary cortisol. Some inconsistencies in the patterns may be explained by differences in the sampling of data. Future research should try to delineate possible relationships between EDA and hormones on all levels of the hypothalamic-pituitary-adrenocortical axis.