The prevalence and morbidity of chronic fatigue and chronic fatigue syndrome: a prospective primary care study.

Abstract
OBJECTIVES: This study examined the prevalence and public health impact of chronic fatigue and chronic fatigue syndrome in primary care patients in England. METHODS: There were 2376 subjects, aged 18 through 45 years. Of 214 subjects who fulfilled criteria for chronic fatigue, 185 (86%) were interviewed in the case-control study. Measures included chronic fatigue, psychological morbidity, depression, anxiety, somatic symptoms, symptoms of chronic fatigue syndrome, functional impairment, and psychiatric disorder. RESULTS: The point prevalence of chronic fatigue was 11.3%, falling to 4.1% if comorbid psychological disorders were excluded. The point prevalence of chronic fatigue syndrome was 2.6%, falling to 0.5% if comorbid psychological disorders were excluded. Rates did not vary by social class. After adjustment for psychological disorder, being female was modestly associated with chronic fatigue. Functional impairment was profound and was associated with psychological disorder. CONCLUSIONS: Both chronic fatigue and chronic fatigue syndrome are common in primary care patients and represent a considerable public health burden. Selection bias may account for previous suggestions of a link with higher socioeconomic status.