CARDIOVASCULAR TESTS OF AUTONOMIC FUNCTION AND SYMPATHETIC SKIN-RESPONSES IN PATIENTS WITH MAJOR DEPRESSION

To assess the function of the autonomic nervous system in major depres sion, a series of cardiovascular tests, together with the recording of sympathetic skin response, were performed in 18 depressed patients (m elancholic type, DSM-III-R criteria) and in 18 healthy control subject s. Depressed patients showed significantly poorer performance in Valsa lva's, deep breathing, and lying to standing manoeuvres than controls, indicating an impairment of parasympathetic function. Depressed patie nts developed a significantly larger sympathetic skin response than co ntrols during the lying to standing and hand grip manoeuvres, whereas cardiovascular sympathetic performance (as assessed by the responses t o hand grip, cold, mental arithmetic, explosive sound, or hyperventila tion) was similar in both groups. The results are compatible with the view that a diminished parasympathetic reactivity, and presumably an i ncreased sympathetic reactivity, occur in patients with major depressi on.