Douleur chronique : comorbidité anxiodépressive et ségrégation corticale

Chronic pain has deleterious consequences on the quality of life, including on mood. Indeed, depression and anxiety are often observed in chronic pain patients. While this comorbidity is clinically well-established, the underlying mechanisms remain to be detailed. In the recent years, the development of relevant preclinical animal models allowed determining causal relations between chronic pain and mood disorders. These models also provided mechanistic insights. Morphofunctional alterations in the anterior cingulate cortex, the nucleus accumbens and the hippocampus in neuropathic pain, some genetic polymorphisms and environmental factors in fibromyalgia, and changes in the balance between pro- and anti-inflammatory cytokines and the role of the amygdala in inflammatory pain, contribute to the anxiodepressive symptoms accompanying chronic pain. Data also suggest that different mechanisms may underlie the consequences of different types of chronic pain. Preclinical work also completes clinical data to understand the separated cortical processing of the various components of chronic pain, in particular, its sensory and its emotional components. Between the clinic and the lab, present translational effort allows progressing in understanding the pain/depression comorbidity.