[Depression and pain: novel clinical, neurobiological and psychopharmacological data]

Abstract

Epidemiological studies confirm frequent appearance of pain symptoms in depressive patients and a marked prevalence of depression in pain conditions. These observations seem to point at a close intertwining between mood regulation and pain perception. In the pathogenesis of both depression and pain symptoms, an important role has been attributed to disturbances of serotonergic and noradrenergic neurotransmission as well as to neuropeptides such as opioids and substance P. In mood regulation as well as in the perception and emotional dimension of pain stimuli, such brain structures as the amygdala, anterior cingulate cortex and prefrontal cortex are of main significance. The action of antidepressant drugs results in a normalization of the activity of those neurotransmitter systems and brain structures. It was found that dual action antidepressants (i.e. influencing both serotonergic and noradrenergic system) such as tricyclic antidepressants and new generation drugs (venlafaxine, milnacipram, duloxetine, mirtazapine) exert a stronger antidepressant effect and possess a broader therapeutic spectrum, including also an effect on pain symptoms. These drugs have been also increasingly used for the treatment of pain symptoms in somatic illnesses (e.g. diabetic neuropathy, fibromyalgia).