Endocrine Abstracts

Chronic fatigue syndrome (CFS) comprises a number of symptoms which include fatigue, headaches, poor concentration, muscle and joint pains and sleep disturbance. The first working case definition was formulated by the Centres for Disease Control in 1988, and two modifications have been published - a British definition in 1991 and a second American definition in 1994. The most important factor in all definitions is severe fatigue. The British definition requires that both mental and physical functioning be affected and other physical symptoms may or may not be present. The American definition requires four other physical symptoms. A single cause for CFS has not been established and the syndrome probably has a variety of disease mechanisms. The diagnosis of CFS rests on symptoms described, and no confirmatory laboratory tests are available. Treatment therefore concentrates on symptoms such as pain, sleep disruption and exhaustion. There have been 44 published treatment trials that meet the requirements of the National Health Service Centre for Reviews and Dissemination. The interventions used included graded exercise therapy, cognitive behaviour therapy, immunoglobulins, hydrocortisone and other pharmacological agents such as antidepressants. General conclusions are difficult to make as different studies have used different case definitions, different exclusion criteria and different outcome measures. Three randomised controlled trials (RCTs) have shown a benefit of graded exercise therapy (GET) and three of four RCTs have shown a positive effect of cognitive behaviour therapy (CBT). The trials of GET and those showing a positive effect of CBT score highly on validity assessments. The management of patients with severe fatigue involves a detailed assessment, with exclusion of other disorders especially depression and sleep disorders. The worst affected patients may not be suitable for CBT or exercise therapy, and conversely mildly affected patients might require little formalised treatment.