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Published on: May 31, 2016
Impaired mental health and low-grade inflammation among fatigued bereaved individuals
Annina Seiler1, Kyle W Murdock2, Christopher P Fagundes3
1Department of Consultation-Liaison-Psychiatry and Psychosomatic Medicine, University Hospital Zurich, Switzerland.
Background:
Fatigue is a common symptom in stressed individuals. Bereavement is a major life event that has been associated with impaired mental health. Little research has investigated the prevalence of fatigue and its inflammatory correlates in bereaved individuals.
Objectives:
To assess fatigue prevalence and its relationship with mental health outcomes and markers of inflammation, as indexed by C-reactive protein (CRP), interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) in bereaved individuals.
Methods:
Seventy-eight-bereaved adults were examined for fatigue (SF-36 energy/vitality scale), perceived stress (PSS), depression (CES-D), sleep quality (PSQI), pain (SF-36 pain scale), and general health (SF-36 general), and their serum levels of CRP, IL-6 and TNF-α were measured. Group differences between fatigued versus non-fatigued individuals were estimated using analysis of covariance (ANCOVA), with adjustment for body mass index (BMI).
Results:
Fatigued bereaved individuals (33%; SF-36 energy/vitality score 0-45) had significantly higher CRP levels (p < .05) as compared to non-fatigued bereaved individuals and reported higher levels of pain (p < .001), greater stress (p < .001), depression (p < .001), and sleeping problems (p < .001), as well as poorer social functioning (p < .001) and general health (p < .001) than those in the non-fatigued group. No group differences were found for IL-6 and TNF-α.
Conclusions:
Fatigued bereaved individuals showed elevated systemic inflammation as measured by CRP in comparison to non-fatigued bereaved individuals. They were also more likely to report mental health problems that co-occur with fatigue in the context of immune activation. Continued research is needed to help clarify the involvement of inflammatory markers in the development of fatigue in a larger sample of bereaved adults.
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