From Current Psychiatry Reports, 15 April 2013.
The neuropsychiatric and neuropsychological features of chronic fatigue syndrome: revisiting the enigma.
Christley Y, Duffy T, Everall IP, Martin CR.
School of Health, Nursing and Midwifery, University of the West of Scotland, Ayr Campus, University Avenue, Ayr, KA8 0SX, UK. yvonne.christley@uws.ac.uk
Abstract
The aim of this article is to provide a comprehensive and updated review of the key neuropsychiatric and neuropsychological complaints associated with chronic fatigue syndrome (CFS). Neuropsychiatric and neuropsychological difficulties are common in CFS and are linked primarily to disorders of mood, affect and behaviour.
The neuropsychiatric complaint most frequently encountered amongst CFS patients is depression and in particular major depressive disorder (MDD). Despite decades of research, the precise aetiological relationship between CFS and MDD remains poorly understood. This has resulted in the development of a number of interesting and polarised hypotheses regarding the aetiological nature of CFS.
Recent scientific advances have however begun to unravel a number of interesting inflammatory and immunological explanations that suggest CFS and MDD are distinct yet interrelated conditions. The possibility that the overlap between CFS and MDD might be explained in terms of shared oxidative and nitrosative (IO&NS) pathways is an area of intense research interest and is reviewed in detail in this article.
The overlap between CFS and MDD is further differentiated by variations in HPA axis activity between the two disorders.
Important immunological differences between MDD and CFS are also reviewed with particular emphasis on antiviral RNase L pathways in CFS.
In addition to the presence of neuropsychiatric complaints, CFS is also associated with neuropsychological symptoms such as impaired attention, memory and reaction time. The key neuropsychological problems reported by CFS patients are also included in the review in an effort to understand the significance of cognitive impairment in CFS.
From Fatigue, Biomedicine, Health and Behavior, 6 December 2014.
Chronic fatigue syndrome and co-morbid and consequent conditions: evidence from a multi-site clinical epidemiology study
Lucinda Bateman(ab), Salima Darakjy(c), Nancy Klimas(bd), Daniel Peterson(be), Susan M. Levine(bf), Ali Allen(ab), Shane A. Carlson(ab), Elizabeth Balbin(g), Gunnar Gottschalke & Dana March(c*).
a) Fatigue Consultation Clinic, Salt Lake City, UT, USA
b) Chronic Fatigue Initiative, New York, USA
c) Department of Epidemiology, Columbia University, New York, USA
d) Departments of Medicine and Clinical Immunology, Nova Southeastern University, Miami, FL, USA
e) Sierra Internal Medicine, Incline Village, NV, USA
f) Susan Levine, MD, Private Practice, New York, USA
g) Department of Psychology and Behavioral Medicine, University of Miami, Miami, FL, USA
Abstract
BACKGROUND
Epidemiologic data that inform our understanding of the type, frequency, and burden of co-morbidities with chronic fatigue syndrome is limited.
PURPOSE
To elucidate co-morbid and consequent conditions, using data from a clinical epidemiology study of long-term CFS patients.
METHODS
Some 960 adults with CFS were identified at four sites specializing in the diagnosis and treatment of CFS. Patients reported their demographics, CFS course, other medical diagnoses, and current functioning. We determined associations between: co-morbidities and a patient's current health relative to their health when diagnosed with CFS; CFS symptom severity at onset and subsequent diagnosis with a co-morbid condition; and presence of a co-morbidity and functional ability. We also modeled the change in CFS symptom severity over time as it relates to the presence of a co-morbidity.
RESULTS
Of the sample, 84% was diagnosed with one or more co-morbid conditions after CFS onset. Fibromyalgia, depression, anxiety, and hypothyroidism were the most common diagnoses. Nearly 60% of the sample reported a mental illness.
CONCLUSIONS
In general, co-morbid conditions reduced functional ability and were associated with the worsening of CFS symptoms over time. This study provides important new information on the prevalence of co-morbid conditions and their impact on the course of CFS.