Objectives. To review the literature addressing the relationship between mood disorders and fibromyalgia/chronic pain and our current understanding of overlapping pathophysiological processes and pain and depression circuitry. Methods. We selectively reviewed articles on the co-occurrence of mood disorders and fibromyalgia/chronic pain published between 1990 and July 2012 in PubMed. Bibliographies and cross references were considered and included when appropriate. Results. Forty-nine out of 138 publications were retained for review. The vast majority of the studies found an association between depression and fibromyalgia. There is evidence that depression is often accompanied by symptoms of opposite polarity characterised by heights of mood, thinking and behaviour that have a considerable impact on pharmacological treatment. Recent developments support the view that the high rates of fibromyalgia and mood disorder comorbidity is generated by largely overlapping pathophysiological processes in the brain, that provide a neurobiological basis for the bidirectional, mutually exacerbating and disabling relationship between pain and depression. Conclusions. The finding of comparable pathophysiological characteristics of pain and depression provides a framework for understanding the relationship between the two conditions and sheds some light on neurobiological and therapeutic aspects.
Depression, fibromyalgia, pain, comorbidity