Functional status, neuropsychological functioning, and mood in chronic fatigue syndrome (CFS): relationship to psychiatric disorder

Abstract:

Individuals with chronic fatigue syndrome (CFS) face chronic physical debilitation, reduced neuropsychological functioning, and changes in emotional well-being that significantly detract from quality of life. The role of psychiatric disturbance in reducing quality of life in CFS remains unclear. In the current investigation, the role of psychiatric status in reducing health-related quality of life in CFS was examined.

Four subject groups were compared on measures of functional well-being, mood, and neuropsychological status: individuals with CFS and no history of psychiatric illness, individuals who had current symptoms of psychiatric illness that began after their CFS diagnosis, individuals who had current symptoms of psychiatric illness that began before their CFS diagnosis, and a healthy sedentary control group.

Overall, it was found that individuals with CFS suffer from profound physical impairment. Concurrent psychiatric illness, however, did not adversely affect physical functional capacity. Physical functional capacity was not worse in individuals with a concurrent psychiatric illness. As expected, concurrent psychiatric illness was found to reduce emotional well-being. Moreover, individuals with a psychiatric illness that predated the onset of CFS suffered the greatest emotional distress. Thus, an individual’s psychiatric history should be considered when attempting to understand the factors maintaining disability in CFS.

 

Source: Tiersky LA, Matheis RJ, Deluca J, Lange G, Natelson BH. Functional status, neuropsychological functioning, and mood in chronic fatigue syndrome (CFS): relationship to psychiatric disorder. J Nerv Ment Dis. 2003 May;191(5):324-31. http://www.ncbi.nlm.nih.gov/pubmed/12819552

 

Observer independent analysis of cerebral glucose metabolism in patients with chronic fatigue syndrome

Abstract:

OBJECTIVES: To evaluate cerebral glucose metabolism, assessed by 18-fluorodeoxyglucose positron emission tomography (FDG-PET), in patients with chronic fatigue syndrome (CFS), using an observer independent analytical approach; and to characterise any observed alterations by correlating them with neuropsychological deficits.

METHODS: 26 patients (13 female, 13 male) were examined. They all fulfilled the CDC diagnostic criteria for CFS. Their ages ranged from 26 to 61 years (mean (SD) age, 43 (9.3) years). They underwent extensive psychometric testing including the hospital anxiety and depression scale (HADS) and the short form 36 item health questionnaire (SF-36). Brain FDG-PET was done in all the subjects. After stereotactic normalisation, single subject comparisons with an age and sex matched normal database (n = 18) and a group comparison between the patients and normal controls were undertaken, along with additional correlation analyses between brain metabolism and psychometric test scores.

RESULTS: 12 of the 26 patients showed no significant decrease in FDG uptake compared with the controls. Of the remaining 14, 12 showed hypometabolism bilaterally in the cingulate gyrus and the adjacent mesial cortical areas. Five of these 12 patients also had decreased metabolism in the orbitofrontal cortex. The two remaining patients had hypometabolism in the cuneus/praecuneus. Correlation analyses showed significant correlations between some test scores (anxiety, depression, health related quality of life) but not fatigue and regional reductions in glucose metabolism.

CONCLUSIONS: Although abnormalities in FDG-PET were only detectable in approximately half the CFS patients examined, and no specific pattern for CFS could be identified, PET may provide valuable information in helping to separate CFS patients into subpopulations with and without apparent alterations in the central nervous system.

 

Source: Siessmeier T, Nix WA, Hardt J, Schreckenberger M, Egle UT, Bartenstein P. Observer independent analysis of cerebral glucose metabolism in patients with chronic fatigue syndrome. J Neurol Neurosurg Psychiatry. 2003 Jul;74(7):922-8. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1738575/ (Full article)

 

 

Experimental evidence for interpretive but not attention biases towards somatic information in patients with chronic fatigue syndrome

Abstract:

OBJECTIVE: This study tested whether CFS patients have an attentional information processing bias for illness-related information and a tendency to interpret ambiguous information in a somatic fashion.

DESIGN: 25 patients meeting research criteria for a diagnosis of CFS were compared to 24 healthy matched controls on a modified Stroop task and an ambiguous cues task.

METHOD: In the modified Stroop task, participants colour named a series of somatic, depressed and neutral words in order to ascertain whether the somatic words were more distracting to the CFS patients than the depressed and neutral words when compared to controls. In the ambiguous cues task, participants were presented with a tape-recorded list of 30 words including 15 ambiguous illness words (e.g., vein/vain) and 15 unambiguous words. For each word, they were asked to write down the first word that came into their head. A somatic bias score was obtained for each subject by summing the number of somatic responses to the ambiguous word cues.

RESULTS: Although CFS patients were significantly slower in colour naming all of the Stroop word categories than controls, there was no evidence for illness or depressed words creating greater interference than neutral words. However, on the ambiguous cues task, CFS patients made significantly more somatic interpretations than controls and this bias was significantly associated with the extent to which they currently reported symptoms.

CONCLUSION: CFS patients have an interpretive bias for somatic information which may play a part in the maintenance of the disorder by heightening patients’ experience of physical symptoms and helping to maintain their negative illness schemas. Although patients did not show an attentional bias in this study, this may be related to the methodology employed.

 

Source: Moss-Morris R, Petrie KJ. Experimental evidence for interpretive but not attention biases towards somatic information in patients with chronic fatigue syndrome. Br J Health Psychol. 2003 May;8(Pt 2):195-208. http://www.ncbi.nlm.nih.gov/pubmed/12804333

 

Mark Twain and his family’s health: Livy Clemens’ neurasthenia in the gilded age and chronic fatigue syndrome of today

Abstract:

Our purpose is to compare and contrast the 19th century diagnosis and disease neurasthenia with the contemporary illness known as Chronic Fatigue Syndrome. The health of Mark Twain’s wife, Olivia (Livy) Clemens, will then be discussed and evaluated with respect to these two medical conditions.

 

Source: Arcari R, Crombie HD. Mark Twain and his family’s health: Livy Clemens’ neurasthenia in the gilded age and chronic fatigue syndrome of today. Conn Med. 2003 May;67(5):293-6. http://www.ncbi.nlm.nih.gov/pubmed/12802844

 

An approach to chronic fatigue syndrome in adults

Abstract:

BACKGROUND: The neurologist is often asked to evaluate patients with a chief complaint of fatigue. Many neurologists do not believe in the pathologically based disease known as chronic fatigue syndrome, yet as a group, neurologists are well suited to guide the diagnostic work up of such patients to pinpoint treatable disorders in the realm of neurology, general medicine, and psychiatry.

REVIEW SUMMARY: Every patient should be carefully evaluated for certain medical, psychiatric, and neurologic disease that can cause fatigue as the most prominent symptom. This is most pressing because new work in virology, immunology, and imaging holds promise but still does not provide any diagnostic test or a mechanism for the production of these symptoms. Only a few treatments meet with even modest success in CFS. The goal of this paper is to provide the clinical neurologist with a framework for the investigation and management of this challenging group of patients.

CONCLUSIONS: Neurologists are typically also trained in psychiatry and general medicine, and this is a strong position to evaluate the patient with fatigue. Because no presently available test can make the diagnosis of CFS, the assessment is vital to seek out more treatable illnesses.

 

Source: Sabin TD. An approach to chronic fatigue syndrome in adults. Neurologist. 2003 Jan;9(1):28-34. http://www.ncbi.nlm.nih.gov/pubmed/12801429

 

Deficit in motor performance correlates with changed corticospinal excitability in patients with chronic fatigue syndrome

Abstract:

Chronic fatigue syndrome (CFS) is characterised by fatigue and musculosketetal pain, the severity of which is variable. Simple reaction times (SRTs) and movement times (SMTs) are slowed in CFS. Our objective is to correlate the day-to-day changes in symptomatology with any change in SRT, SMT or corticospinal excitability.

Ten CFS patients were tested on two occasions up to two years apart. Motor evoked potentials (MEPs) to transcranial magnetic stimulation (TMS) of the motor cortex were recorded from the thenar muscles. Threshold TMS strength to evoke MEPs was measured to index corticospinal excitability. SRTs and SMTs were measured.

The percentage change in both SRTs and SMTs between the two test sessions correlated with the percentage change in corticospinal excitability assessed according to threshold TMS intensity required to produce MEPs. This study provides evidence that changing motor deficits in CFS have a neurophysiological basis. The slowness of SRTs supports the notion of a deficit in motor preparatory areas of the brain.

 

Source: Davey NJ, Puri BK, Catley M, Main J, Nowicky AV, Zaman R. Deficit in motor performance correlates with changed corticospinal excitability in patients with chronic fatigue syndrome. Int J Clin Pract. 2003 May;57(4):262-4. http://www.ncbi.nlm.nih.gov/pubmed/12800454

 

Assessing chronic fatigue

Comment on: The head-up tilt test with haemodynamic instability score in diagnosing chronic fatigue syndrome. [QJM. 2003]

 

Naschitz et al.1 studied patients with chronic fatigue syndrome (CFS) in comparison with some controls ‘exhibiting shared clinical features with CFS’, namely, patients with non-CFS chronic fatigue, fibromyalgia, generalized anxiety disorder, and neurally mediated syncope. Considering that those controls were included in the study on the basis of the clinical overlap of their disorders with CFS, it is surprising that Naschitz et al. failed to include also patients with Addison’s disease, which resembles CFS far more closely than does any other medical condition.2

You can read the rest of this comment here: http://qjmed.oxfordjournals.org/content/96/6/454.long

 

Source: Baschetti R. Assessing chronic fatigue. QJM. 2003 Jun;96(6):454. http://qjmed.oxfordjournals.org/content/96/6/454.long (Full article)

 

Chronic phase lipids in sera of chronic fatigue syndrome (CFS), chronic ciguatera fish poisoning (CCFP), hepatitis B, and cancer with antigenic epitope resembling ciguatoxin, as assessed with MAb-CTX

Abstract:

Clinical reports and descriptions of chronic fatigue syndrome (CFS) and chronic ciguatera fish poisoning (CCFP) show great similarities in clinical symptomology. These similarities in the literature suggested the exploration of lipids in sera of CFS, CCFP, and other diseases with the membrane immunobead assay (MIA), which is typically used for screening ciguateric ocean fish. Sera from patients with other diseases, including hepatitis B, cancer, and diabetes, were included to assess the degree of specificity involved.

Sera were treated with acetone in a ratio of 1 part serum to 4 parts acetone. The suspension was centrifuged, and the acetone layer was evaporated. The residue was weighed and redissolved in 1.0 mL methanol and tested by the MIA, undiluted and titered to 1:160. The undiluted acetone fraction of the 37 normal showed +/- activity to +activity with 16 no titer, 15 with 1:5 titer and two with 1:10 titer, and four with > or =1:40 titers. One hundred fifteen CFS sera showed 1 with 1+ and 114 with 2+ activity in the undiluted samples, 1 with 1:10 titer, 3 with 1:20 titer, 31 with 1:40 titer, 50 with 1:80 titer, and 30 with 160 titer. Thus 95.6% of the samples had > or =1:40 titer.

Eight hepatitis B sera samples had > or =1:40 titers. Four CCFP samples had > or =1:40 titers. Three of 16 cancer samples had 1:40 titer. These data are summarized in Fig. 1. As shown in Table 1, a significant increase (P<0.001) in the chronic phase lipids (CPLs) was shown relative to the normal group. A preliminary chemical study in C18 octadecylsilyl columns showed all fractions (100% chloroform, 9:1 chloroform : methanol, 1:1 chloroform : methanol, and 100% methanol) to contain lipids reactive to MAb-CTX with different intensities. Prostaglandins were shown in 100% methanol fraction.

Competitive MIA with crude fish ciguatoxin and CFS with synthetic JKLM ciguatoxin epitope suggested similarities in structure with ciguatoxin. This was compatible with the neuroblastoma assay demonstrated in the C(18) column fractions 9:1 and 1:1, chloroform : methanol solvents.

Copyright 2003 John Wiley & Sons, Ltd.

 

Source: Hokama Y, Uto GA, Palafox NA, Enlander D, Jordan E, Cocchetto A. Chronic phase lipids in sera of chronic fatigue syndrome (CFS), chronic ciguatera fish poisoning (CCFP), hepatitis B, and cancer with antigenic epitope resembling ciguatoxin, as assessed with MAb-CTX. J Clin Lab Anal. 2003;17(4):132-9. http://www.ncbi.nlm.nih.gov/pubmed/12784262

 

Subclassifying chronic fatigue syndrome through exercise testing

Abstract:

PURPOSE: The purpose of this study was to examine physiological responses of persons with chronic fatigue syndrome (CFS) to a graded exercise test.

METHODS: Cardiopulmonary exercise tests were performed on 189 patients diagnosed with CFS. Based on values for peak oxygen consumption, patients were assigned to one of four impairment categories (none, mild, moderate, and severe), using American Medical Association (AMA) guidelines. A one-way MANOVA was used to determine differences between impairment categories for the dependent variables of age, body mass index, percentage of predicted [OV0312]O(2), resting and peak heart rates, resting and peak systolic blood pressure, respiratory quotient (RQ), and rating of perceived exertion.

RESULTS: Significant differences were found between each impairment level for percentage of predicted [OV0312]O(2) and peak heart rate. Peak systolic blood pressure values for the “moderate,” and “severe” groups differed significantly from each other and both other groups. The more impaired groups had lower values. The no impairment group had a significantly higher peak RQ than each of the other impairment levels (all P < 0.001). Peak [OV0312]O(2) values were less than predicted for all groups. Compared with the males, the women achieved actual values for peak [OV0312]O(2) that were closer to their predicted values.

CONCLUSION: Despite a common diagnosis, the functional capacity of CFS patients varies greatly. Stratifying patients by function allows for a more meaningful interpretation of the responses to exercise and may enable differential diagnosis between subsets of CFS patients.

Comment in: Physiological factors limiting exercise performance in CFS. [Med Sci Sports Exerc. 2004]

 

Source: Vanness JM, Snell CR, Strayer DR, Dempsey L 4th, Stevens SR. Subclassifying chronic fatigue syndrome through exercise testing. Med Sci Sports Exerc. 2003 Jun;35(6):908-13. http://www.ncbi.nlm.nih.gov/pubmed/12783037

 

Fatigue, burnout, and chronic fatigue syndrome among employees on sick leave: do attributions make the difference?

Abstract:

BACKGROUND: Persistent fatigue among employees, burnout, and chronic fatigue syndrome (CFS) are three fatigue conditions that share some characteristics in theory. However, these conditions have not been compared in empirical research, despite conceptual similarities.

METHODS: This cross sectional study aimed to investigate relations between persistent fatigue, burnout, and CFS by describing the clinical features of a sample of 151 fatigued employees on sick leave. Using validated instruments, subgroups based on research criteria for CFS and burnout within the sample of fatigued employees and a reference group of 97 diagnosed CFS patients were compared. Analyses of covariance were performed.

RESULTS: A total of 66 (43.7%) fatigued employees met research criteria for CFS (except symptom criteria) and 76 (50.3%) met research criteria for burnout. “CFS-like employees” (fatigued employees who met CFS criteria) reported stronger somatic attributions than “non-CFS-like employees”. Burnt out CFS-like employees were more depressed and distressed than CFS-like employees who were not burnt out. Burnout cases among the non-CFS-like employees had stronger psychological attributions than fatigued employees who were not burnt out. Compared to diagnosed CFS patients, CFS-like employees merely had a shorter duration of fatigue complaints. Burnt out CFS-like employees had stronger psychological attributions and were more distressed than CFS patients.

CONCLUSIONS: Fatigued employees shared many important characteristics with CFS patients, regardless of burnout status, and many fatigued employees met CFS criteria and/or burnout criteria. Differences however concerned the causal attributions that were made. This raises questions about the role of causal attributions: are they modified by fatigue complaints or do they determine illness outcome?

 

Source: Huibers MJ, Beurskens AJ, Prins JB, Kant IJ, Bazelmans E, Van Schayck CP, Knottnerus JA, Bleijenberg G. Fatigue, burnout, and chronic fatigue syndrome among employees on sick leave: do attributions make the difference? Occup Environ Med. 2003 Jun;60 Suppl 1:i26-31. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1765721/ (Full article)