Fatigue: Biomedicine, Health & Behavior - Volume 5, Issue 3, 2017

Volume 5, Issue 3, 2017

 * Distinct evening fatigue profiles in oncology outpatients receiving chemotherapy"Abstract - Background: Fatigue is the most common and debilitating symptom experienced by oncology patients during chemotherapy (CTX). Fatigue severity demonstrates a large amount of inter-individual and diurnal variability. Purpose: Study purposes were to evaluate for subgroups of patients with distinct evening fatigue profiles and evaluate how these subgroups differed on demographic, clinical, and symptom characteristics. Methods: Outpatients with breast, gastrointestinal, gynecological, or lung cancer (n = 1332) completed questionnaires six times over two cycles of CTX. Lee Fatigue Scale evaluated evening fatigue severity. Latent profile analysis was used to identify distinct evening fatigue profiles. Results: Four distinct evening fatigue classes (i.e. Low (14.0%), Moderate (17.2%), High (36.0%), and Very High (32.8%)) were identified. Compared to the Low class, patients in the Very High evening fatigue class were: younger, female, had childcare responsibilities, had more years of education, had a lower functional status, had a higher comorbidity burden, and were diagnosed with breast cancer. Patients in the Very High class reported higher levels of depressive symptoms, sleep disturbance, and evening fatigue at enrollment. Conclusions: Findings provide new insights into modifiable risk factors for higher levels of evening fatigue. Clinicians can use this information to identify higher risk patients and plan appropriate interventions."
 * Dysregulation of cytokine pathways in chronic fatigue syndrome and multiple sclerosis"Abstract - Background: Cytokine studies in chronic fatigue syndrome (CFS) have yielded mixed findings. Purpose: This investigation evaluated whether network analysis of cytokine production differs between patients with CFS and multiple sclerosis (MS) as compared to a reference group of healthy controls. Methods: Three subgroups (N = 109) were included: 15 participants who met diagnostic criteria for CFS, 57 participants meeting criteria for MS, and 37 controls. Peripheral blood was obtained and production of a select cytokine profile was determined from stimulated and unstimulated mononuclear cells. Data were generated through the use of a multi-analyte bead suspension array. Pairwise associations were determined for each group, and these associations were used to create a graphical representation of the data. The graph was clustered using an eigenvector community algorithm and results visualized using edges to model the correlations by color and thickness to show direction and strength. Results: The control and MS groups produced a three-neighborhood relationship regardless of cell condition. While producing a three-neighborhood relationship, the MS group differed significantly from the control group as it displayed stronger relationships among pro-inflammatory cytokines. In contrast, the CFS group displayed a three-neighborhood solution when unstimulated. However, when cells from the CFS group were stimulated, a two-neighborhood model was found that exhibited stronger inter-cytokine correlations. The model found in CFS was significantly different from that found in the control and MS groups. Conclusion: CFS was characterized by a pattern of global immunologic activation using network analysis, fundamentally different from those found for either MS or control groups."
 * Incidence of myalgic encephalomyelitis/chronic fatigue syndrome in a large prospective cohort of U.S. nurses "Abstract: Background: The incidence of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), the rates of both under-diagnosis and over-diagnosis, and the nature of the onset of the condition have not been assessed in large studies of health professionals. Purpose: To determine the cumulative incidence of ME/CFS in a large population of health professionals, to examine the nature of the onset of the illness, and to estimate the frequency of both over-diagnosis and under-diagnosis of ME/CFS. Methods: We sent an email questionnaire to participants in the Nurses’ Health Study II (NHS II), a large prospective cohort of female nurses. Forty-two thousand three hundred and ninety-four women completed the questionnaire, which included the 1994 Centers for Disease Control and Prevention (CDC) criteria for ME/CFS. Results: One-hundred and two women (240 per 100,000 surveyed) developed an illness that met criteria for ME/CFS between 1989 and 2009. The onset of ME/CFS was gradual in 40.6%, sudden (following flu-like illness or other precipitating events) in 18.8%, followed emotional or physical trauma in 32.3%, and was uncertain in the rest. Under-diagnosis was common: only 15 (15%) of the women who met criteria for ME/CFS reported having been diagnosed. Over-diagnosis also was common: four times as many subjects had been diagnosed with ME/CFS by community doctors as actually met criteria. The distribution of symptoms was not different in comparing cases with a sudden onset to those with a gradual onset. Conclusions: In this large cohort of female nurses, we found a low cumulative incidence of ME/CFS. Over-diagnosis and under-diagnosis were high, even in this medically sophisticated population."
 * What is known about severe and very severe chronic fatigue syndrome? A scoping review"Abstract - Background: Chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) affects 0.4% of the population. It is characterised by disabling fatigue and a combination of self-reported symptoms which include impairments in concentration, short-term memory, sleep disturbances, post-exertional malaise and musculoskeletal pain. There are four categories of severity in the CFS/ME population: mild; moderate; severe; and very severe which are expanded on elsewhere and adopted by the National Institute for Health and Care Excellence [NICE. Chronic fatigue syndrome/myalgic encephelomyelitis diagnosis and management in adults and children; 2007]. Objective: Identify research relating to those severely and very severely affected by CFS/ME. Methods: We searched electronic databases for relevant studies using pre-defined search terms: ‘chronic fatigue syndrome’ and ‘sever$’ which covers ‘severe’ and ‘severely’. Included were English language papers published in full that discretely identified severely and very severely affected CFS/ME populations from the broader CFS/ME population. Results: Over 2000 papers were reviewed and 21 papers met the selection criteria. The capture produced both adult and paediatric populations with a variety of methodologies. Wide differences in illness characterisation, definition and measurement were found. Case studies reported that in extreme presentations very severe CFS/ME individuals may be confined to bed, requiring reduced light and noise exposure. Conclusion: This review highlights the limited research focusing on the severely affected CFS/ME population. The heterogeneity of the condition contributes to the lack of consensus concerning definitive diagnostic criteria and functional measures to assess disability. Focused research to understand the disease characteristics of the most severely ill will help to advance our understanding of possible phenotypes associated with distinct severity categories."
 * Letter to the Editor: Cardiac sympathetic innervation associates with autonomic dysfunction in chronic fatigue syndrome – a pilot study, by George Petrides, Pawel Zalewski, David McCulloch, Laura Maclachlan, Andreas Finkelmeyer, Tim Hodgson, Andrew Blamire & Julia L. Newton
 * Letter to the Editor: Symptoms of chronic fatigue syndrome/myalgic encephalomyelitis in security workers in Bogota, Colombia, by Edna X. Rincon, Diego Hererra & Jonathan R. Kerr