Fatigue: Biomedicine, Health & Behavior - Volume 2, Issue 3, 2014

Volume 2, Issue 3, 2014

 * Fatigue in mothers of infants and young children: factor structure of the fatigue assessment scale "Abstract - Background: Fatigue is a common experience among mothers of young children, yet there are few well validated tools to assess fatigue in mothers. Purpose: The aim of this paper was to examine the suitability, construct validity, and reliability of the Fatigue Assessment Scale (FAS). Method: Participants were 779 mothers of young children (aged 0–5 years) living in Australia who participated in an online survey about parent health and wellbeing. Results: Confirmatory factor analysis revealed that both one- and two-factor models representing physical and cognitive aspects of fatigue, with modifications, were an adequate fit to the data. Modified versions demonstrated high internal consistency. Measurement invariance was also established across mothers in the postnatal period and mothers of older children. Conclusions: The utility of the FAS in assessing maternal fatigue is discussed, along with implications for clinical use and future research."
 * Validating a measure of myalgic encephalomyelitis/chronic fatigue syndrome symptomatology "Abstract - Background: The diagnosis of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is complex and largely based on self-reported symptom profiles. The field lacks consensus for a singular case definition and heterogeneous samples make comparability across studies difficult. Purpose: The present study sought to validate a comprehensive self-report measure of ME/CFS symptomatology to aid in clinical and research assessment. Methods: Exploratory factor analysis (EFA) was used to establish the underlying factor structure of the DePaul Symptom Questionnaire (DSQ) using a well-characterized sample of individuals (92.6% met the Fukuda et al. criteria and/or the Clinical Canadian Criteria) and this structure was then tested on a less stringently recruited sample of individuals utilizing a confirmatory factor analysis (CFA). Convergent and discriminant validity of the DSQ were also examined utilizing alternative measures of symptomatology and functioning. Results: A three-factor solution was found using EFA (Neuroendocrine, Autonomic, and Immune Symptoms; Neurological/Cognitive Dysfunction; Post-Exertional Malaise) and the fit of this factor structure was adequate for the second sample. The DSQ was found to have good convergent and discriminant validity. Conclusions: The DSQ is a valid tool for assessing ME/CFS symptoms. There may be two core ME/CFS symptom clusters: post-exertional malaise and cognitive dysfunction."
 * High rates of fatigue in newly diagnosed Graves' disease "Abstract - Background: Fatigue in patients with Graves’ disease has rarely been addressed. Purpose: To investigate the presence of subjective fatigue as well as cognitive fatigability among patients with untreated Graves' disease. Methods: Thirty-four patients (mean age: 39.2 ± 9.8) with newly diagnosed untreated Graves' disease and 31 healthy controls (mean age 36.7 ± 8.8) were investigated. The Digit Symbol Substitution Test was used for assessment of cognitive fatigability and the Fatigue Severity Scale (FSS) and the Everyday Consequences of Fatigue (ECF) questionnaire were used to assess self-rated effects of fatigue on activities and motivation. Results: Patients scored significantly higher on self-rated fatigue impact (FSS) than controls (p < 0.001) and 56% of patients reached a clinical level of fatigue impact. Half of the patients suffered from cognitive fatigability compared to 19% of the controls (p = 0.010). High free triiodothyronine (T3) levels were associated with ECF scores. Depression was associated with self-rated fatigue impact but not with cognitive fatigability. Free T3 correlated significantly with consequences of fatigue among the fatigued patients, while free T3 correlated significantly with incidental memory among the non-fatigued patients. Conclusions: The results suggest that both subjective fatigue impact and cognitive fatigability are common in untreated Graves' disease and that thyroid hormone levels might have differential effects on fatigue impact and memory in different individuals."
 * The role of sleep in chronic fatigue syndrome: a narrative review "Abstract - Background: Chronic Fatigue Syndrome (CFS) affects 0.23–2.6% of the adult population. Sleep-related complaints are amongst the most frequently reported symptoms in these patients. Although a biopsychosocial model of CFS offers a plausible framework for understanding the condition, the role of sleep and how it functions within this model remains unclear. Purpose: This narrative review describes the findings of studies of sleep in CFS and considers the reasons behind the diversity of results. The review also discusses the difficulties that exist in establishing relationships between sleep, behaviour, cognition, physiology, and the physical symptoms of CFS. Methods: A search of Medline for the terms “CFS,” “chronic fatigue syndrome,” AND “sleep” was performed to identify articles concerning sleep and CFS from 1988 to the present. Results: Subjective sleep dysfunction was frequently reported in the CFS sleep studies. However, objective sleep research in CFS has shown no consistent picture of sleep disturbance, particularly with regard to polysomnography. This may be attributable to the heterogeneity of sleep phenotypes in the CFS population as well as the variability in sleep assessment protocols, case definitions, and exclusion criteria used across studies. Conclusions: Given the high prevalence of disturbed sleep in this population in combination with inconsistent findings, exploration of new protocols for the objective assessment of sleep in CFS (e.g., three-night PSG protocol) is recommended. Understanding the distinct sleep characteristics in this population could serve to improve insight into perpetuating factors of CFS symptoms which is relevant for diagnosis and therapy."