Neurophysiologic tests during antidepressive treatment - An exploratory study

This is a non-randomized exploratory study showing the sensitivity of neuro physiological parameters for autonomic side-effects during the application of antidepressant drugs. inpatients on tricyclic antidepressants (TCA: amit riptyline or doxepine), inpatients on serotonine-reuptake inhibitors (SSRI: fluvoxamine or paroxetin) and a control group of healthy volunteers underw ent neurophysiological examination. The treatment group was investigated af ter at least 7 days of continuous treatment with the final dose. Adjustment of the autonomic nervous system was studied, first, by measuring latency a nd amplitude of the sympathetic skin response (SSR), elicited by electric s timuli and by deep inspiration, and second, by analysis of the heart rate v ariation (HRV) during rest and inspiration. Relevant affections of the peri pheral parts of the reflex are under discussion were excluded by taking the nerve conduction Velocity (NCV) and F-wave referring to cervical segment C 7. In total, 48 individuals were examined. The TCA group showed delayed lat encies and smaller amplitudes of the SSR in comparison with the controls. I n the SSRI group, these parameters did not differ significantly from those of the controls. Analysis of HRV put further emphasis on the impaired adjus tment of the autonomic nervous system in the TCA group. To sum up, our test battery indicated a specific vegetative alteration due to TCA.