Chronic fatigue disorders: an inappropriate response to arginine vasopressin?

Abstract:

Chronic fatigue disorders are characterized by a subjectively defined group of symptoms such as chronic fatigue, mental confusion, exertional malaise, weight changes, and/or diffuse multi-joint pains.

Significant clinical overlap exists between chronic fatigue disorders and the syndrome of serum inappropriate anti-diuretic hormone (SIADH). Both chronic fatigue disorders and SIADH are characterized by lethargy and mental confusion. Both disorders can be induced or exacerbated by viral illnesses, physical exertion, emotional stress and/or hypotension. Both can be treated with salt loading and glucocorticoids.

Therefore, altered water metabolism resulting from inappropriate release and/or response to arginine vasopressin (AVP) is proposed as a pathophysiological basis of certain chronic fatigue disorders. Moreover, these data suggest that salt loading and/or direct inhibition of AVP may be an effective therapeutic approach in individuals with chronic fatigue disorders.

 

Source: Peroutka SJ. Chronic fatigue disorders: an inappropriate response to arginine vasopressin? Med Hypotheses. 1998 Jun;50(6):521-3. http://www.ncbi.nlm.nih.gov/pubmed/9710328

 

Evidence for and pathophysiologic implications of hypothalamic-pituitary-adrenal axis dysregulation in fibromyalgia and chronic fatigue syndrome

Abstract:

Chronic fatigue syndrome (CFS) is characterized by profound fatigue and an array of diffuse somatic symptoms.

Our group has established that impaired activation of the hypothalamic-pituitary-adrenal (HPA) axis is an essential neuroendocrine feature of this condition. The relevance of this finding to the pathophysiology of CFS is supported by the observation that the onset and course of this illness is excerbated by physical and emotional stressors. It is also notable that this HPA dysregulation differs from that seen in melancholic depression, but shares features with other clinical syndromes (e.g., fibromyalgia).

How the HPA axis dysfunction develops is unclear, though recent work suggests disturbances in serotonergic neurotransmission and alterations in the activity of AVP, an important co-secretagogue that, along with CRH, influences HPA axis function.

In order to provide a more refined view of the nature of the HPA disturbance in patients with CFS, we have studied the detailed, pulsatile characteristics of the HPA axis in a group of patients meeting the 1994 CDC case criteria for CFS. Results of that work are consistent with the view that patients with CFS have a reduction of HPA axis activity due, in part, to impaired central nervous system drive. These observations provide an important clue to the development of more effective treatment to this disabling condition.

 

Source: Demitrack MA, Crofford LJ. Evidence for and pathophysiologic implications of hypothalamic-pituitary-adrenal axis dysregulation in fibromyalgia and chronic fatigue syndrome. Ann N Y Acad Sci. 1998 May 1;840:684-97. http://www.ncbi.nlm.nih.gov/pubmed/9629295