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Twin analyses of fatigue
Ellen Schur1, Niloofar Afari, Jack Goldberg
11 Department of Medicine, University of Washington School of Medicine, Seattle,Washington, USA. ellschur@washington.edu
Summary
Genetic and environmental factors influence prolonged and chronic fatigue differently in men and women. While males show significant genetic contributions, females
Area of Science:
- Behavioral Genetics
- Epidemiology
- Psychiatry
Background:
- Prolonged fatigue (>1 month) and chronic fatigue (>6 months) are common clinical issues with unknown causes.
- Chronic fatigue syndrome (CFS) shares etiological and epidemiological challenges.
- Twin studies offer insights into genetic and environmental influences on fatigue.
Purpose of the Study:
- To investigate genetic and environmental influences on prolonged fatigue, chronic fatigue, and CFS using twin modeling.
- To determine if these influences differ between genders.
Main Methods:
- Biometrical structural equation twin modeling applied to data from 1042 monozygotic (MZ) and 828 dizygotic (DZ) twin pairs.
- Assessment of three fatigue variables: prolonged fatigue, chronic fatigue, and CFS.
- Analysis of additive genetic, shared environmental, and individual-specific environmental effects.
Main Results:
- In men, genetic effects accounted for approximately half the variance in prolonged and chronic fatigue, with the remainder due to individual-specific environments.
- In women, individual-specific environmental effects largely explained the variance in prolonged and chronic fatigue.
- Gender differences in genetic and environmental influences were observed for prolonged fatigue, chronic fatigue, and CFS.
Conclusions:
- Genetic and environmental factors play distinct roles in the development of fatigue symptoms, with significant gender-specific variations.
- Understanding these influences is crucial for developing targeted interventions for fatigue and CFS.
- Further research is needed to fully elucidate the complex interplay of factors contributing to fatigue.
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