The interface between chronic fatigue syndrome and depression: A psychobiological and neurophysiological conundrum.

The chronic fatigue syndrome (CFS) remains a contentious and controversial presentation despite decades of systematic research from a variety of medical specialties and associated disciplines. Variously championed as a condition of immunological, neurological, neurophysiological, psychiatric or psychological origin, consensus on a cogent and evidenced-based pathway has yet to be achieved. Irrespective of the ambiguity regarding aetiology, what is incontrovertible is the experience of significant depression, which often accompanies this most distressing clinical presentation. The current paper examines the potential underlying mechanisms, which may determine and explain this relationship between CFS and depression. In doing so, it offers some insights, which may be of value in the development of evidence-based and scientifically-anchored interventions in individuals experiencing this diagnosis, to improve outcomes in relation to depression specifically and quality of life more generally.