CFS and FM appear to have more common points than they do differences.46 The relationship between major depression and severe chronic fatigue can be investigated biologically. Fatigue is of course a common symptom of depression. The findings from investigation of neuropsychological function echo the pattern of broad similarities and some potentially defining differences: depressed patients showed marked diurnal variation

in motor function and more severe memory impairment.47 Patients with chronic fatigue syndrome also show a specific sensitivity to Inhibitors,research,lifescience,medical the effects of exertion on effortful cognitive functioning, not seen in major depression. This occurs despite subjective and Inhibitors,research,lifescience,medical objective evidence of effort allocation in chronic fatigue syndrome. It suggests that patients have reduced working memory capacity, or a greater demand to monitor cognitive processes, or both.48 this website Comorbidity is also seen with irritable bowel syndrome (IBS). A systematic review of all the comorbidity studies of IBS49 showed that the disorders with the best-documented association were fibromyalgia (median of 49% have IBS), chronic fatigue syndrome (51%), temporomandibular joint disorder (64%), and chronic pelvic pain (50%). Major depression, anxiety, and other psychiatric disorders occurred in up to 94% of

IBS cases. The treatment of these conditions is as controversial Inhibitors,research,lifescience,medical as their diagnosis has often been. There are advocates of antidepressants, graded exercise, and Inhibitors,research,lifescience,medical cognitive behavior therapy (CBT). In some cases it is confusing. Thus, in one trial, CBT was shown to be superior to a more simple intervention.50 In another, it was comparable to counseling.51 The evidence supporting all the available interventions Inhibitors,research,lifescience,medical remains limited52 and the cost of providing

them potentially quite high. Antidepressants are probably widely prescribed, although their value in primary care remains uncertain. Conclusion The challenge of the mood disorders lies in their apparently rising incidence and prevalence, the realization that long-term disability Isotretinoin and even mortality is likely to be increasingly evident, and the need for better delivery of more effective treatments. Their association with other disorders may provide clues to etiology, especially relating to brain mechanisms underlying reward and stress/autonomic regulation. The greatest uncertainty relates to their co-occurrence with somatic syndromes which are common and poorly understood. There is a risk that the ubiquitous use of the term depression is becoming potentially counterproductive. There is a danger that, just as the authenticity of cases of functional disturbance or somatization is frequently doubted, so depression diagnoses now come to be seen as little more than endorsements of minor distress.