Patients with chronic fatigue syndrome and accurate feeling-of-knowing judgments

Abstract:

Many Chronic Fatigue Syndrome (CFS) patients complain of memory impairments which have been difficult to document empirically. Subjective complaints of memory impairment may be due to a deficit in metamemory judgment. CFS patients and matched controls were tested with a computerized Trivia Information Quiz that required them to rate their confidence about correctly recognizing an answer in a multiple choice format that they had been unable to remember in a fact-recall format. Even though CFS patients reported significantly greater amounts of fatigue, cognitive, and physical symptoms, the accuracy of their confidence levels and recognition responses were similar to controls. This finding suggests that a metamemory deficit is not the cause of the memory problems reported by CFS patients.

 

Source: Lakein DA, Fantie BD, Grafman J, Ross S, O’Fallon A, Dale J, Straus SE. Patients with chronic fatigue syndrome and accurate feeling-of-knowing judgments. J Clin Psychol. 1997 Nov;53(7):635-45. http://www.ncbi.nlm.nih.gov/pubmed/9356893

 

Decreased postexercise facilitation of motor evoked potentials in patients with chronic fatigue syndrome or depression

Abstract:

We studied the effects of exercise on motor evoked potentials (MEPs) elicited by transcranial magnetic stimulation (TMS) in 18 normal (control) subjects, 12 patients with chronic fatigue syndrome, and 10 depressed patients. Subjects performed repeated sets of isometric exercise of the extensor carpi radialis muscle until they were unable to maintain half maximal force.

MEPs were recorded before and after each exercise set and for up to 30 minutes after the last set. The mean amplitude of MEPs recorded from the resting muscle immediately after each exercise set was 218% of the mean pre-exercise MEP amplitude in normal subjects, 126% in chronic fatigue patients, and 155% in depressed patients, indicating postexercise MEP facilitation in all three groups. The increases in the patient groups, however, were significantly lower than normal.

The mean amplitudes of MEPs recorded within the first few minutes after the last exercise sets in all three groups were approximately half their mean pre-exercise MEP amplitudes. This postexercise MEP depression was similar in all groups. We conclude that postexercise cortical excitability is significantly reduced in patients with chronic fatigue syndrome and in depressed patients compared with that of normal subjects.

 

Source: Samii A, Wassermann EM, Ikoma K, Mercuri B, George MS, O’Fallon A, Dale JK, Straus SE, Hallett M. Decreased postexercise facilitation of motor evoked potentials in patients with chronic fatigue syndrome or depression. Neurology. 1996 Dec;47(6):1410-4. http://www.ncbi.nlm.nih.gov/pubmed/8960719

 

Chronic fatigue syndrome

“Biopsychosocial approach” may be difficult in practice

This week a joint working group of the Royal Colleges of Physicians, Psychiatrists, and General Practitioners in Britain issued a report on chronic fatigue syndrome.’ The report constitutes, arguably, the finest contemporary position statement in the field, and physicians and patients are well advised to read it, but it is sure to engender disagreement on both sides of the Atlantic.

The term chronic fatigue syndrome is relatively new. It first appeared in the 1988 proposal by the United States Centers for Disease Control to formalise a working case definition for symptoms that had been variously named and attributed to numerous causes for over two centuries. Through field testing, the case definition was revised and simplified in 1994. In essence, it classifies a constellation of prolonged and debilitat ing symptoms as worthy of medical attention and study (see box). Related case criteria were developed by consensus at Oxford in 199 .4 Neither the American nor the Oxford criteria assume the syndrome to be a single nosological entity. As the royal colleges’ report concludes, the term chronic fatigue syndrome is appropriate because it carries none of the inaccurate aetiological implications of the alternative acronyms-myalgic encephalomyelitis, chronic fatigue syndrome, and immune dysfunction syndrome.

You can read the rest of this comment here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2359057/pdf/bmj00562-0007.pdf

 

Source: Straus SE. Chronic fatigue syndrome. BMJ. 1996 Oct 5;313(7061):831-2. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2359057/

 

A cluster of cases of chronic fatigue and chronic fatigue syndrome: clinical and immunologic studies

Chronic fatigue syndrome (CFS) is characterized by unexplained, persistent fatigue and other symptoms including arthralgias, myalgias, cognitive impairment, and depression [1, 2]. It has been postulated that infectious agents play a role in both sporadic cases and clustered cases of CFS [3- 5].

We were notified of a cluster of CFS cases that occurred in a women’s residential facility; these cases were associated with an influenza-like outbreak in February 1990. We conducted a study of these events in 1993. Between 1990 and 1993,36 women had lived in the facility. Sixteen of these residents reported fatigue that lasted more than or equal to1 month during the 3-year study interval. Two of the residents who entered the facility before 1990 already had fatigue. Five residents stated that the onset of fatigue corresponded to the outbreak of the influenza-like illness. Nine women described no temporal relationship between their fatigue and the “flu” outbreak. The fatigue resolved in two of these nine women after several weeks, while it persisted in the other seven. Evaluations were performed for these seven residents, and diagnoses including lupus, ulcerative colitis, or hyperparathyroidism were considered for three, but no cause for the fatigue was established for the other four.

You can read the rest of this article here: http://cid.oxfordjournals.org/content/23/2/408.long

 

Source: Levine PH, Dale JK, Benson-Grigg E, Fritz S, Grufferman S, Straus SE. A cluster of cases of chronic fatigue and chronic fatigue syndrome: clinical and immunologic studies. Clin Infect Dis. 1996 Aug;23(2):408-9. http://www.ncbi.nlm.nih.gov/pubmed/8842294

 

The chronic fatigue syndrome: a comprehensive approach to its definition and study. International Chronic Fatigue Syndrome Study Group

Abstract:

The complexities of the chronic fatigue syndrome and the methodologic problems associated with its study indicate the need for a comprehensive, systematic, and integrated approach to the evaluation, classification, and study of persons with this condition and other fatiguing illnesses. We propose a conceptual framework and a set of guidelines that provide such an approach. Our guidelines include recommendations for the clinical evaluation of fatigued persons, a revised case definition of the chronic fatigue syndrome, and a strategy for subgrouping fatigued persons in formal investigations.

Comment in:

The chronic fatigue syndrome. [Ann Intern Med. 1995]

The chronic fatigue syndrome. [Ann Intern Med. 1995]

The chronic fatigue syndrome. [Ann Intern Med. 1995]

The chronic fatigue syndrome. [Ann Intern Med. 1995]

 

Source: Fukuda K, Straus SE, Hickie I, Sharpe MC, Dobbins JG, Komaroff A. The chronic fatigue syndrome: a comprehensive approach to its definition and study. International Chronic Fatigue Syndrome Study Group. Ann Intern Med. 1994 Dec 15;121(12):953-9. http://www.ncbi.nlm.nih.gov/pubmed/7978722

 

Chronic fatigue syndrome: point and counterpoint

Abstract:

Two clinical investigators with divergent views on chronic fatigue syndrome (CFS) were invited to debate their positions at the 1993 annual meeting of The Infectious Disease Society of America. Major points of the discourse focused on the value of the US Centers for Disease Control and Prevention case definition of CFS, the potential roles of infectious and allergic problems in the syndrome, the confounding problem of concurrent psychiatric problems, and the utility of diagnostic tests.

 

Source: Straus SE, Komaroff AL, Wedner HJ. Chronic fatigue syndrome: point and counterpoint. J Infect Dis. 1994 Jul;170(1):1-6. http://www.ncbi.nlm.nih.gov/pubmed/8014482

 

Analysis of neuropsychological functioning in patients with chronic fatigue syndrome

Abstract:

Memory impairment dominates the cognitive complaints of patients with chronic fatigue syndrome (CFS). Twenty CFS patients were available for studies with a clinical and experimental battery composed of memory and cognitive tests. The results on objective testing indicated that the CFS patients had some mild memory impairment, but only on tasks requiring conceptually driven encoding and retrieval processes. There were no associations between the nature of the precipitating illness, self ratings of fatigue, physical findings, or laboratory determination and objective memory performance or self report of memory functioning. These generally negative results indicate that memory impairment in CFS patients is typically mild and involves memory processes that participate in conceptualising information.

 

Source: Grafman J, Schwartz V, Dale JK, Scheffers M, Houser C, Straus SE. Analysis of neuropsychological functioning in patients with chronic fatigue syndrome. J Neurol Neurosurg Psychiatry. 1993 Jun;56(6):684-9. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC489620/ (Full article)

 

Studies of herpesvirus infection in chronic fatigue syndrome

Abstract:

The relationship of herpesviruses to chronic fatigue syndrome has received considerable attention over the past decade. Data suggesting an association fall into three major categories.

First, among acute precipitants of the syndrome are primary infections with some herpesviruses, most notably Epstein-Barr virus and cytomegalovirus.

Second, a series of studies have detailed elevations of antibodies to most herpesviruses in selected chronic fatigue syndrome populations, with Epstein-Barr virus and human herpes type 6 being the objects of most scrutiny.

Third, one recent study reported a greater ease of recovery of human herpes virus type 6 from chronic fatigue syndrome patients. This review article critically examines the cumulative data regarding an association between one or more herpesviruses and the chronic fatigue syndrome in the context of the known biology and epidemiology of these agents.

In view of these, and additional considerations regarding study methodologies, the conclusion is drawn that herpesviruses are not dominant causes of the chronic fatigue syndrome and may not even be necessary to the perpetuation of the illness, but it is premature to dismiss entirely this latter possibility.

 

Source: Straus SE. Studies of herpesvirus infection in chronic fatigue syndrome. Ciba Found Symp. 1993;173:132-9; discussion 139-45. http://www.ncbi.nlm.nih.gov/pubmed/8387907

 

Lymphocyte phenotype and function in the chronic fatigue syndrome

Abstract:

Lymphocytes of 18 patients meeting the Centers for Disease Control (CDC) case definition for the chronic fatigue syndrome (CFS), 10 similar, chronically fatigued patients not fully conforming to the CDC case definition, and 17 matched, healthy individuals were studied to determine the presence of abnormalities of peripheral cell phenotype and function.

Extensive phenotypic analyses of B- and T-cell subsets, natural killer (NK) cells, and macrophages were performed using single-, dual-, and three-color flow cytometry. Compared to controls, in CFS patients the percentage of CD4 T cells and CD4,CD45RA, or naive T cells, was reduced. The CD4,CD45RO, or memory T-cell, subset was numerically normal but expressed increased levels of adhesion markers (CD29, CD54, and CD58). CFS patient lymphocytes showed reduced proliferative responses to phytohemagglutinin, concanavalin A, and staphylococcal enterotoxin B. Lymphocytes from fatigue patients not meeting the CDC definition showed similar abnormalities.

These data indicate that peripheral T cells manifest an increased state of differentiation in CFS and related conditions. This may arise as a consequence of an underlying neuropsychiatric and/or neuroendocrine disorder or because of exposure to antigens or superantigens of an infectious agent.

 

Source: Straus SE, Fritz S, Dale JK, Gould B, Strober W. Lymphocyte phenotype and function in the chronic fatigue syndrome. J Clin Immunol. 1993 Jan;13(1):30-40. http://www.ncbi.nlm.nih.gov/pubmed/8095270

 

Plasma and cerebrospinal fluid monoamine metabolism in patients with chronic fatigue syndrome: preliminary findings

Abstract:

The syndrome of chronic fatigue, feverishness, diffuse pains, and other constitutional complaints, often precipitated by an acute infectious illness and aggravated by physical and emotional stressors, has a lengthy history in the medical literature.

The Centers for Disease Control (CDC) recently formulated a case definition, renaming the illness “chronic fatigue syndrome.” Nevertheless, there remain few biological data that can validate the existence of this syndrome as distinct from a wide variety of other, largely psychiatric disorders, and little understanding of its pathogenesis.

In the present study, basal plasma and cerebrospinal fluid levels of the monoamine metabolites, 3-methoxy-4-hydroxyphenylglycol (MHPG), 5-hydroxyindoleacetic acid (5-HIAA), and homovanillic acid (HVA) were determined in 19 patients meeting CDC research case criteria for chronic fatigue syndrome and in 17 normal individuals.

Patients with chronic fatigue syndrome showed a significant reduction in basal plasma levels of MHPG and a significant increase in basal plasma levels of 5-HIAA. Although the functional significance of these findings has not been definitively elucidated, they are compatible with the clinical presentation of a syndrome associated with chronic lethargy and fatigue, and with evidence of persistent immune stimulation, and lend support to the idea that chronic fatigue syndrome represents a clinical entity with potential biological specificity.

 

Source: Demitrack MA, Gold PW, Dale JK, Krahn DD, Kling MA, Straus SE. Plasma and cerebrospinal fluid monoamine metabolism in patients with chronic fatigue syndrome: preliminary findings. Biol Psychiatry. 1992 Dec 15;32(12):1065-77. http://www.ncbi.nlm.nih.gov/pubmed/1282370