This Article  • Full text  • PDF  • Reply to article  • Send to a friend  • Save in My Folder  • Save to citation manager  • Permissions  Citing Articles  • Citation map  • Citing articles on HighWire  • Citing articles on Web of Science (14)  • Contact me when this article is cited  Related Content  • Similar articles in this journal  Topic Collections  • Neurology  • Stress  • Musculoskeletal Syndromes (Chronic Fatigue, Gulf War)  • Prognosis/ Outcomes  • Alert me on articles by topic  Social Bookmarking   What's this?

Kenji Kato, PhD; Patrick F. Sullivan, MD, FRANZCP; Birgitta Evengård, MD, PhD; Nancy L. Pedersen, PhD

Arch Gen Psychiatry. 2006;63:1267-1272.

Context  Chronic fatigue syndrome is a disabling problem characterized by persistent fatigue lasting at least 6 months with a number of ancillary symptoms. Although the etiology of chronic fatiguing illness is unknown, some evidence suggests that stress may confer increased risk for development of the disorder. Moreover, subjects with chronic fatiguing illness may have distinctive personality traits, although this finding could reflect confounding by other mechanisms.

Objective  To assess the prospective association of premorbid self-reported stress and personality with chronic fatigue–like illness.

Design  Prospective nested case-control study in a population-based sample.

Setting  General community.

Participants  From the Swedish Twin Registry, 19 192 twins born between January 1, 1935, and December 31, 1958.

Main Outcome Measures  Information about current chronic fatiguing illnesses was obtained from computer-assisted telephone interviews conducted between 1998 and 2002. Self-reported stress (based on a single question) and personality scales (emotional instability and extraversion in the Eysenck Personality Inventory) were measured from 1972 to 1973 by a mailed questionnaire. Relative risks were estimated with case-control analyses (matched for age and sex) and co-twin control analyses (comparing discordant pairs).

Results  Higher emotional instability and self-reported stress in the premorbid period were associated with higher risk for chronic fatigue–like illness in matched case-control analyses (odds ratios, 1.72 and 1.64, respectively). In co-twin control analyses, relative risk of emotional instability decreased to 1.02 whereas that of stress increased considerably to 5.81. There was no association between extraversion and fatigue.

Conclusions  Elevated premorbid stress is a significant risk factor for chronic fatigue–like illness, the effect of which may be buffered by genetic influences. Emotional instability assessed 25 years earlier is associated with chronic fatigue through genetic mechanisms contributing to both personality style and expression of the disorder. These findings suggest plausible mechanisms for chronic fatiguing illness.

Author Affiliations: Department of Medical Epidemiology and Biostatistics (Drs Kato, Sullivan, and Pedersen) and Department of Laboratory Medicine, Karolinska University Hospital Huddinge (Dr Evengård), Karolinska Institutet, Stockholm, Sweden; Departments of Genetics, Psychiatry, and Epidemiology, University of North Carolina at Chapel Hill (Dr Sullivan); and Department of Psychology, University of Southern California, Los Angeles (Dr Pedersen).

CiteULike    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter     What's this?

THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES

Etiology of Chronic Fatigue Syndrome: Testing Popular Hypotheses Using a National Birth Cohort Study
Harvey et al.
Psychosom. Med. 2008;70:488-495.
ABSTRACT | FULL TEXT  

Rehabilitation of decreased motor performance in patients with chronic fatigue syndrome: should we treat low effort capacity or reduced effort tolerance?
Van Houdenhove et al.
Clin Rehabil 2007;21:1121-1142.
ABSTRACT