From BMC Medicine, an open-access journal, published on 21 March 2011

Chronic fatigue syndrome in an ethnically diverse population: the influence of psychosocial adversity and physical inactivity

Kamaldeep S Bhui^1* , Sokratis Dinos^1* , Deborah Ashby^2* , James Nazroo^3* , Simon Wessely^4* and Peter D White^1*

¹ Centre for Psychiatry, Wolson Institute of Preventive Medicine, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK

² Division of Epidemiology, Public Health and Primary Care, Imperial College London, UK

³ School of Social Sciences, University of Manchester, Manchester, UK

⁴ Department of Psychological Medicine and Psychiatry, Institute of Psychiatry, King's College London, London, UK

author email corresponding author email* Contributed equally

BMC Medicine 2011, 9:26doi:10.1186/1741-7015-9-26

The electronic version of this article is the complete one and can be found online at: http://www.biomedcentral.com/1741-7015/9/26

© 2011 Bhui et al; licensee BioMed Central Ltd.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Background

Chronic fatigue syndrome (CFS) is a complex multifactorial disorder. This paper reports the prevalence of chronic fatigue (CF) and CFS in an ethnically diverse population sample and tests whether prevalence varies by social adversity, social support, physical inactivity, anxiety and depression.

Methods

Analysis of survey data linking the Health Survey for England (1998 and 1999) and the Ethnic Minority Psychiatric Illness Rates in the Community (EMPIRIC) study undertaken in 2000. The study population comprised a national population sample of 4,281 people ages 16 to 74 years. CF and CFS were operationally defined on the basis of an interview in the EMPIRIC study, alongside questions about psychosocial risk factors. Previous illnesses were reported in the Health Survey for England during 1998 and 1999, as was physical inactivity.

Results

All ethnic minority groups had a higher prevalence of CFS than the White group. The lowest prevalence was 0.8% in the White group, and it was highest at 3.5% in the Pakistani group (odds ratio (OR), 4.1; 95% confidence interval (95% CI), 1.6 to 10.4). Anxiety (OR, 1.8; 95% CI, 1.4 to 2.2), depression (OR, 1.4; 95% CI, 1.1 to 1.8), physical inactivity (OR, 2.0; 95% CI, 1.1 to 3.8), social strain (OR, 1.24; 95% CI, 1.04 to 1.48) and negative aspects of social support (OR, 2.12; 95% CI, 1.4 to 3.3) were independent risk factors for CFS in the overall sample. Together these risk factors explained ethnic differences in the prevalence of CFS, but no single risk factor could explain a higher prevalence in all ethnic groups.

Conclusions

The prevalence of CFS, but not CF, varies by ethnic group. Anxiety, depression, physical inactivity, social strain and negative aspects of social support together accounted for prevalence differences of CFS in the overall sample.