Onset Patterns and Course of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Background: Epidemiologic studies of myalgic encephalomyelitis/ chronic fatigue syndrome (ME/CFS) have examined different aspects of this disease separately but few have explored them together. Objective: Describe ME/CFS onset and course in one United States-based cohort. Methods: One hundred and fifty subjects fitting Fukuda 1994 CFS criteria completed a detailed survey concerning the initial and subsequent stages of their illness. Descriptive statistics, graphs, and tables were used to illustrate prevalence and patterns of characteristics. Results: The most common peri-onset events reported by subjects were infection-related episodes (64%), stressful incidents (39%), and exposure to environmental toxins (20%). For 38% of subjects, more than 6 months elapsed from experiencing any initial symptom to developing the set of symptoms comprising their ME/CFS. Over time, the 12 most common symptoms persisted but declined in prevalence, with fatigue, unrefreshing sleep, exertion-related sickness, and flu-like symptoms declining the most (by 20-25%). Conversely, cognitive symptoms changed the least in prevalence, rising in symptom ranking. Pregnancy, menopause, and menstrual cycles exacerbated many women's symptoms. Fatigue-related function was not associated with duration of illness or age; during the worst periods of their illness, 48% of subjects could not engage in any productive activity. At the time of survey, 47% were unable to work and only 4% felt their condition was improving steadily with the majority (59%) describing a fluctuating course. Ninety-seven percent suffered from at least one other illness: anxiety (48%), depression (43%), fibromyalgia (39%), irritable bowel syndrome (38%), and migraine headaches (37%) were the most diagnosed conditions. Thirteen percent came from families where at least one other first-degree relative was also afflicted, rising to 27% when chronic fatigue of unclear etiology was included. Conclusions: This paper offers a broad epidemiologic overview of one ME/CFS cohort in the United States. While most of our findings are consistent with prior studies, we highlight underexamined aspects of this condition (e.g., the evolution of symptoms) and propose new interpretations of findings. Studying these aspects can offer insight and solutions to the diagnosis, etiology, pathophysiology, and treatment of this condition.

Chronic fatigue and sociodemographic characteristics as predictors of psychiatric disorders in a community-based sample

OBJECTIVES

To explore the roles of chronic fatigue and sociodemographic characteristics (eg, parental status, work status, socioeconomic status, sex, age, marital status, and ethnicity) as predictors of psychiatric disorders.

METHODS

A stratified random sample of 18,675 adults residing in diverse neighborhoods in Chicago completed a telephone-screening questionnaire. A control group without chronic fatigue (N = 74) and a group of individuals with chronic fatigue (N = 227) were identified and administered a semi-structured psychiatric interview. Stepwise logistic regression analyses predicting occurrence of current and lifetime psychiatric disorders according to chronic fatigue status and sociodemographics were conducted on this overall sample of 301 participants.

RESULTS

Chronic fatigue, low socioeconomic status, and unemployment were among significant predictors of overall Axis I psychiatric disorders. Chronic fatigue functioned as a predictor for mood and anxiety disorders (including posttraumatic stress disorder), but did not function as a predictor for somatoform disorders, substance abuse/dependence, and eating disorders. Low socioeconomic status and unemployment were significantly associated with current psychiatric disorder, and low socioeconomic status was also significantly associated with mood and anxiety disorders. Women were significantly more likely to experience mood disorder, and minorities (eg, African Americans, Latinos, and individuals of other ethnicity) were significantly more likely to report posttraumatic stress disorder.

CONCLUSIONS

Results support prior findings for increased rates of psychiatric disorder among individuals with chronic fatigue and highlight the roles of low socioeconomic status, unemployment, being a woman, and being classified as a minority in their association with certain psychiatric disorders.

Chronic fatigue syndrome: lactic acid bacteria may be of therapeutic value

Chronic fatigue syndrome (CFS) is complex illness with unknown aetiology. Recent research shows that patients with CFS have marked alterations in microbial flora, including lowered levels of bifidobacteria and small intestinal bacterial overgrowth (SIBO). Research also indicates that CFS patients are under increased oxidative stress, have a type 2 helper cell dominate cytokine profile, frequently report allergies, have altered essential fatty acid (EFA) status and may have malabsorption of certain micronutrients. Lactic acid bacteria (LAB) have the potential to influence the immune system in CFS patients by supporting T helper cell 1 driven cellular immunity and may decrease allergies. In addition LAB are strong antioxidants, may improve EFA status, can enhance absorption of micronutrients by protecting the intestinal epithelial barrier, and have been used to treat SIBO. It is our contention that LAB may have a therapeutic role in the treatment of CFS.

Chronic fatigue syndrome: neurological findings may be related to blood--brain barrier permeability

Despite volumes of international research, the etiology of chronic fatigue syndrome (CFS) remains elusive. There is, however, considerable evidence that CFS is a disorder involving the central nervous system (CNS). It is our hypothesis that altered permeability of the blood-brain barrier (BBB) may contribute to ongoing signs and symptoms found in CFS. To support this hypothesis we have examined agents that can increase the blood-brain barrier permeability (BBBP) and those that may be involved in CFS. The factors which can compromise the normal BBBP in CFS include viruses, cytokines, 5-hydroxytryptamine, peroxynitrite, nitric oxide, stress, glutathione depletion, essential fatty acid deficiency, and N-methyl-D-aspartate overactivity. It is possible that breakdown of normal BBBP leads to CNS cellular dysfunction and disruptions of neuronal transmission in CFS. Abnormal changes in BBBP have been linked to a number of disorders involving the CNS; based on review of the literature we conclude that the BBB integrity in CFS warrants investigation.

Symptom patterns in long-duration chronic fatigue syndrome

OBJECTIVE

Our objective was to evaluate symptom patterns in patients with chronic fatigue syndrome (CFS) who were ill for 10 or more years.

METHODS

This cross-sectional self-report study compared patient groups with long-duration (median = 18 years; n = 258) and short-duration (median = 3 years; n = 28) CFS to a group of healthy significant others (n = 79) on symptomatic, neurocognitive, and psychological variables. Data were gathered from a 574-item postal questionnaire.

RESULTS

A principal-components analysis of CFS symptom data yielded a three-factor solution: cognitive problems; flu-like symptoms; and neurologic symptoms. Compared with the short-duration CFS group, the long-duration group had significantly higher CFS symptom severity scores (p < 0.04), largely attributable to increased cognitive difficulties. A subgroup comparison of subjects ill for < 3 years versus those ill 4-7 years suggested that denial coping strategies were more likely in those participants with the shorter illness duration. Significant differences between both CFS groups and healthy controls were found in a number of comorbid disorders. Participants with CFS most often endorsed immune/viral abnormalities and persistent stress as important perceived causes of their illness.

CONCLUSION

Participants with long-duration CFS reported a large number of specific cognitive difficulties that were greater in severity than those reported by participants with short-duration CFS. The pattern of comorbid disorders in the CFS groups was consistent with hypersensitivity and viral reactivation hypotheses.

Chronic fatigue syndrome. A practical guide to assessment and management

Chronic fatigue and chronic fatigue syndrome (CFS) have become increasingly recognized as a common clinical problem, yet one that physicians often find difficult to manage. In this review we suggest a practical, pragmatic, evidence-based approach to the assessment and initial management of the patient whose presentation suggests this diagnosis. The basic principles are simple and for each aspect of management we point out both potential pitfalls and strategies to overcome them. The first, and most important task is to develop mutual trust and collaboration. The second is to complete an adequate assessment, the aim of which is either to make a diagnosis of CFS or to identify an alternative cause for the patient's symptoms. The history is most important and should include a detailed account of the symptoms, the associated disability, the choice of coping strategies, and importantly, the patient's own understanding of his/her illness. The assessment of possible comorbid psychiatric disorders such as depression or anxiety is mandatory. When the physician is satisfied that no alternative physical or psychiatric disorder can be found to explain symptoms, we suggest that a firm and positive diagnosis of CFS be made. The treatment of CFS requires that the patient is given a positive explanation of the cause of his symptoms, emphasizing the distinction among factors that may have predisposed them to develop the illness (lifestyle, work stress, personality), triggered the illness (viral infection, life events) and perpetuated the illness (cerebral dysfunction, sleep disorder, depression, inconsistent activity, and misunderstanding of the illness and fear of making it worse). Interventions are then aimed to overcoming these illness-perpetuating factors. The role of antidepressants remains uncertain but may be tried on a pragmatic basis. Other medications should be avoided. The only treatment strategies of proven efficacy are cognitive behavioral ones. The most important starting point is to promote a consistent pattern of activity, rest, and sleep, followed by a gradual return to normal activity; ongoing review of any 'catastrophic' misinterpretation of symptoms and the problem solving of current life difficulties. We regard chronic fatigue syndrome as important not only because it represents potentially treatable disability and suffering but also because it provides an example for the positive management of medically unexplained illness in general.