Number 4 |
1st December 2005 |
PHYSIOLOGY AND BIOCHEMISTRY
|
Cook, DB., Nagelkirk, PR., Peckerman, A., Poluri, A, Mores, J and Natelson, BH. Exercise and cognitive performance in chronic fatigue syndrome. Medicine & Science in Sports & Exercise, 2005, 37, 9, 1460-1467.
The aim of this study was to determine the effect of submaximal steady-state exercise on cognitive performance in patients with CFS alone, CFS with comorbid fibromyalgia (CFS+FM), and sedentary healthy controls (CON).
Twenty CFS-only patients (CDC criteria ’94), 19 CFS+FM, and 26 controls completed a battery of cognitive tests designed to assess speed of information processing, variability, and efficiency. Tests were performed at baseline, immediately before, and twice following 25 minutes of either cycle ergometry set at 40% of peak oxygen capacity or quiet rest.
There were no group differences in average percentage of peak oxygen consumption during exercise (CFS= 45%; CFS+FM= 47%; Control= 43%: p=0.2). There were no significant effects of acute exercise on cognitive performance for any group. At baseline, one-way ANOVA indicated that CFS patients displayed deficits in speed of processing, performance variability, and task efficiency during several cognitive tests compared with healthy controls. However, the CFS+FM patients were not different than controls. Repeated measures ANOVA indicated that across all tests (pre- and postexercise) CFS, but not CFS+FM, were significantly less consistent (p= 0.03) and less efficient (p= 0.01) than controls.
CFS patients without comorbid FM exhibit subtle cognitive deficits in terms of speed, consistency, and efficiency that are not improved or exacerbated by light exercise. Importantly, our data suggest that CFS+FM patients do not exhibit cognitive deficits either pre- or post-exercise. These results highlight the importance of disease heterogeneity in studies determining acute exercise and cognitive function in CFS.
[Ed. Note: There was no effect of exercise on measures of energy and fatigue.]
Nijs, J., Meeus, M., McGregor, NR., Meeusen, R., De Schutter, G., Van Hoof, E and De Meirleir, K. Chronic fatigue syndrome: exercise performance related to immune dysfunction. Medicine & Science in Sports & Exercise, 2005, 37, 10, 1647-1654.
To date, the exact cause of abnormal exercise response in CFS remains to be revealed, but evidence addressing intracellular immune deregulation in CFS is growing. Therefore, the aim of this cross-sectional study was to examine the interactions between several intracellular immune variables and exercise performance in CFS patients.
After venous blood sampling, subjects (16 patients with CFS, CDC criteria ‘94) performed a maximal exercise stress test on a bicycle ergometer with continuous monitoring of cardiorespiratory variables. The following immune variables were assessed: the ratio of 37 kDa Ribonuclease (RNase) L to the 83 kDa native RNase L (using a radiolabeled ligand/receptor assay), RNase L enzymatic activity (enzymatic assay), protein kinase R activity assay (comparison Western blot), elastase activity (enzymatic-colorimetric assay), the percent of monocytes, and nitric oxide determination (for monocytes and lymphocytes; flow cytometry, live cell assay).
Forward stepwise multiple regression analysis revealed 1) that elastase activity was the only factor related to the reduction in oxygen uptake at a respiratory exchange ratio (RER) of 1.0 (R2 =0.53, p<0.002; elastase activity p<0.002); 2) that the protein kinase R activity was the principle factor related to the reduction in workload at RER=1.0; and 3) that elastase activity was the principle factor related to the reduction in percent of target heart rate achieved.
These data provide evidence for an association between intracellular immune deregulation and exercise performance in patients with CFS. To establish a causal relationship, further study of these interactions using a prospective longitudinal design is required.
Gräns, H., Nilsson, P and Evengård, B. Gene expression profiling in the chronic fatigue syndrome. Journal of Internal Medicine, 2005, 258, 4, 388-390.
Letter. The authors wanted to identify genes in peripheral blood mononuclear cells (PBMCs), which may play an important role in the pathogenesis and diagnostics of CFS, using microarray technology. Patients with CFS from a clinic of infectious diseases at a university hospital were stratified according to the Swedish Twin Registry (STR) study findings to sex, illness classification (ICD-10), illness onset type, illness duration and number of symptoms.
The sample comprised 20 Swedish patients with CFS (CDC criteria ’94), and 14 healthy age- and sex-matched volunteers from the hospital employees as controls.
We found no indication of differential expression between the entire patient group and the control group including both sexes. Differences between the sexes were greater than between patients and controls, women clustered into one big group differentiated from men. However, comparing only female patients to female controls indicated significant differential gene activity. Further analysis was performed using only female study participants.
Patients with no previous documented infection and gradual illness onset (n=8) showed significant gene expression differences compared with healthy female controls (n=12). Of the top eight genes, identified by the B-test, five were known and used for further investigation. Significant gene activity difference was detected in three of the five genes (CD83, BOLA1 and NRK1) with real-time PCR. Significance was achieved using both normalization genes, 18S rRNA and GAPDH.
The five genes differentiated all but one of the female patients with non-infectious and gradual illness onset from the healthy controls. Male patients and controls, and female patients from other subgroups did not follow the clustering pattern.
Differences in gene activity were indicated within the patient group, between the illness classification subgroups and illness onset subgroups. However, no statistical significance was achieved. A greater number of patients within some subgroups is probably required. Indications of gene activity differences were also observed between patients with previous infection and sudden illness onset compared with healthy controls. No changes in gene activity over time of CFS illness duration were observed. No differences were observed between patients fulfilling four to five symptoms of the CFS criteria compared with patients fulfilling seven to eight symptoms.
Conclusively, no differential gene expression was identified with classification of patients according to the STR study. The function of the human CD83 gene is not fully known. CD83 expression is lower in the patient group (non-infectious and gradual illness onset) compared with healthy controls. NRK1 and BOLA1 are over-expressed in the patient group. To clarify the role of the three genes in CFS pathogenesis, further studies on a protein level are needed.
Axe, EK., Satz, P., Rasgon, NL and Fawzy, FI. Major Depressive Disorder in chronic fatigue syndrome: a CDC surveillance study. Journal of Chronic Fatigue Syndrome, 2004, 3, 7-23.
To further understand CFS, the Centers for Disease Control (CDC) conducted a Surveillance Study. The CDC partitioned 565 subjects with fatiguing illnesses into four diagnostic groups, one of which met the 1988 CDC criteria for CFS (n=103). The non-CFS groups had either insufficient severity (idiopathic, n=99), medical exclusions (n=101) or prior psychiatric disorders (n=235). The present study reports on the psychiatric features in that study, estimates the time of onset of Major Depressive Disorder (MDD) and looks for possible relationships between 1988 CDC criteria for CFS and psychiatric disorders.
The study design is cross-sectional. The Diagnostic Interview Schedule (DIS) assessed for four Axis I psychiatric disorders. Time of onset of MDD was estimated from the DIS and validated by an examination of the medical records. Odds ratios and confidence intervals were calculated as tests of association between 1988 CDC criteria and psychiatric disorders.
Subjects classified as CFS and non-CFS had similar rates of psychiatric disorders. The rate of somatisation disorder was 5% (women only) compared to 4% in the medical disorders group. A minority of subjects had pre-existing MDD. Three 1988 CDC criteria were associated with current MDD [headache, sleep disturbance, cognitive complaints, NB: not post-exertional fatigue, Ed.] whilst no criteria were associated with prior MDD.
CFS subjects did not demonstrate any unique patterns of psychiatric disorders. MDD may not be an important predisposing factor for CFS or the other fatiguing illnesses. Some 1988 CDC criteria may be preferentially endorsed by subjects with current MDD.
Bazelmans, E., Bleijenberg, G., Voeten, MJM., van der Meer, JWM and Folgering, H. Impact of a maximal exercise test on symptoms and activity in chronic fatigue syndrome. Journal of Psychosomatic Research, 2005, 59, 4, 201-208.
This study examined the effects of exercise on symptoms and activity in CFS.
Twenty patients with CFS (CDC criteria ’94, operationalised) and 20 neighborhood controls performed an incremental exercise test until exhaustion. Fatigue, muscle pain, minutes spent resting, and the level of physical activity were assessed with a self-observation list. Physical activity was also assessed with an actometer. Data were obtained 3 days before the maximal exercise test (MET) up to 5 days thereafter.
For CFS patients, daily observed fatigue was increased up to 2 days after the exercise test. For controls, self-observed fatigue returned to baseline after 2 hours. Both CFS patients and controls spent more minutes resting on the day before and on the day after the MET. For CFS patients, self-observed minutes resting increased on the day of the exercise test. For neither group, a decrease of actometer recorded or self-observed physical activity after exercise was found.
Fatigue in CFS patients increased after exercise, but the level of actual physical activity remained unchanged.
“Contrary to what was expected, the actometer did not reveal a decrease of physical activity after the exercise test”. Only three of the patients were “passive” i.e. comparatively inactive.
Henderson, M and Tannock, C. Use of depression rating scales in chronic fatigue syndrome. Journal of Psychosomatic Research, 2005, 59, 3, 181-184.
The aim of this study was to examine the performance of three commonly used depression rating scales in a hospital sample of patients with CFS. Sixty-one patients with CFS (CDC criteria ’94) completed the General Health Questionnaire (GHQ), the Hamilton Depression Scale (HAM-D) and the depression subscale of the Hospital Anxiety and Depression Scale (HADS-D). Current psychiatric status was assessed using the Structured Clinical Interview for DSM-III-R. Disorders: Patient version (SCID-P). Receiver operating curves were drawn for each of the depression rating scales.
Thirty-one percent of the patients were depressed according to the SCID-P. Using the standard cut-offs, both GHQ and HAM-D overestimated the number of depressed patients, whilst the HADS-D underestimated the number. The receiver operating curves suggest that the optimum cut-offs for GHQ, HAM-D and HADS-D in this population are 7/8, 13/14 and 8/9, respectively.
Standard cut-offs may not be appropriate when using depression rating scales in CFS patients in a tertiary care setting.
Njoku, MG., Jason, LA and Torres-Harding, SR. The relationships among coping styles and fatigue in an ethnically diverse sample. Ethnicity and Health, 2005, 10, 4, 263-278.
The present study focused on coping strategies among African Americans, Latinos, and European Americans with CFS (CDC criteria ’94, n=29) and idiopathic chronic fatigue (ICF, n=41). The coping strategies examined were measured by using the COPE Scales which assess Seeking Emotional Social Support, Positive Reinterpretation and Growth, Acceptance, Denial, Turning to Religion, Behavioral Disengagement, and Focusing on and Venting Emotions. Also used was a questionnaire assessing four specific coping strategies reported by people with CFS (maintaining activity, accommodating to the illness, focusing on symptoms, and information-seeking).
As predicted, African Americans were significantly more likely to turn to religion than European Americans, and Latinos and African Americans used denial significantly more often than European Americans. An additional finding was that focusing on symptoms was associated with greater fatigue and more physical disability among African Americans. Within the Latino sample, acceptance was related to greater fatigue and less physical disability, and greater optimism predicted less mental disability. Among European American participants, maintaining activity was related to less mental disability, and there was an association between accommodating to the illness and physical disability.
These results indicate that coping varies among various ethnic groups with CFS and ICF; however, denial is consistently related to less adaptive outcomes. Therefore, healthcare professionals should find ways to reduce patient use of denial and promote alternative strategies for managing life events.
Richards, J., Turk, J and White, S. Children and adolescents with chronic fatigue syndrome in non-specialist settings. Beliefs, functional impairment and psychiatric disturbance. European Child and Adolescent Psychiatry, 2005, 14, 6, 310-318.
Adolescents with CFS seen in specialist centres have substantial psychological and functional impairment. Beliefs about activity levels may be important in the development of CFS. The aim of this study was to investigate psychological and functional impairment, and beliefs in children and adolescents with CFS (Oxford and CDC criteria ’94, duration >2 months) recruited from non-specialist services. A total of 30 such individuals participated, and 30 young people with Inflammatory Bowel Disease (IBD) formed the comparison group.
All except one of the fatigued children had been ill for at least six months. Emotional symptoms and disorder were high in both groups. In all, 50% of those with CFS and 30% with IBD reached the threshold for emotional disorder according to the Strengths and Difficulties Questionnaire (SDQ) parent report, although this difference did not reach statistical significance. Participants with CFS scored statistically significantly higher on measures of functional impairment, including school non-attendance, compared to those with IBD. According to questionnaire responses, those with CFS were statistically significantly more likely to favour rest rather than exercise compared to those with IBD. Comparison of parental beliefs did not show such a difference.
These young people with CFS were at high risk of psychiatric disorder. They were substantially disabled when compared to individuals with a known chronic illness. Also, as a group, they were characterised by a preference for rest rather than exercise.
[Ed. Note: Although the CFS group had more emotional symptoms, this could be explained solely by the greater degree of impairment and fatigue. For useful comparisons, groups should be matched for level of disability.]
Taylor, RR. Can the social model explain all of disability experience? Perspectives of persons with chronic fatigue syndrome. American Journal of Occupational Therapy, 2005, 59, 5, 497-506.
The purpose of this study was to examine the adequacy of the social model for explaining the disability experience of persons with CFS. This qualitative study examined the experiences of 47 adults with CFS (CDC criteria ’94) participating in a research project that aimed to evaluate a participant-designed rehabilitation program. Data were aggregated from focus group interviews, open-ended questionnaires, progress notes, and from a program evaluation questionnaire. Data analysis was based on a grounded theory approach and used triangulation of multiple data sources and member checks to assure dependability of findings.
Four themes emerged from the analysis: (1) minimization and mistrust of the disability by others; (2) negative experiences of impairment; (3) lack of identification with the disability community; and (4) the focus on advocacy as a quest for legitimacy. These themes varied in the extent to which they conformed to the principles set forth by the social model.
Although the social model has important contributions to lend to occupational therapy practice, it is important to recognize that it may not capture the full reality of disability. In particular, the social model has serious limitations in describing the disability experience of individuals with disabilities who do not have visibly obvious disabilities and whose impairments do not conform to the traditional viewpoint of disability.
[Ed. Note: This article gives a particularly realistic view of the illness.]
Mears, T. Acupuncture in the treatment of post viral fatigue syndrome - a case report. Acupuncture in Medicine, 2005, 23, 3, 141-145.
This case report concerns the treatment of post viral fatigue (chronic fatigue syndrome) with electroacupuncture. This condition is particularly difficult to treat whether using conventional or complementary therapy. Whilst the treatment did not cure the patient, it appears to have facilitated her return to work and markedly improved her symptoms. There are few publications on acupuncture treatment of this condition and the approach used here has not been reported previously.
Chia, JKS. The role of enterovirus in chronic fatigue syndrome. Journal of Clinical Pathology, 2005, 58, 1126-1132.
Enteroviruses are well known causes of acute respiratory and gastrointestinal infections, with tropism for the central nervous system, muscles, and heart. Initial reports of chronic enteroviral infections causing debilitating symptoms in patients with CFS were met with skeptism, and had been largely forgotten for the past decade. Observations from in vitro experiments and from animal models clearly established a state of chronic persistence through the formation of double stranded RNA, similar to findings reported in muscle biopsies of patients with CFS. Recent evidence not only confirmed the earlier studies, but also clarified the pathogenic role of viral RNA through antiviral treatment. This review summarises the available experimental and clinical evidence that supports the role of enterovirus in CFS.
Garralda, EM and Chadler, T. Practitioner Review: Chronic fatigue syndrome in childhood. Journal of Child Psychology and Psychiatry, 2005, 46, 11, 1143-1151.
Description of the main features of the disorder, precipitating and maintaining factors and diagnostic assessment. Outline of different views on the nature and treatment of CFS in childhood. Description of a rehabilitation program based on cognitive behaviour therapy and graded activity (CBT/GET).
[Ed. Note: The authors ignore evidence which is inconsistent with the theory they are trying to advance, and exaggerate the role of psychiatric variables. The paper also has examples of revisionism and distortion, e.g. “A number of patient support groups … advocate 'pacing' as an approach to rehabilitation which includes avoiding activities. To date there is no empirical evidence for the efficacy of this approach.” Pacing includes avoidance in the same way that graded exercise does. The focus on pacing is on avoidance of overexertion, not activities. There have been a number of trials which used pacing as a principle and which showed a notable degree of improvement, e.g. Wallman et al. Conversely, no trial on CBT\GET has shown that the aim of increasing activity was achieved and that any improvement was therefore a result of an increase in activity.
The authors also cite Speight and Franklin (2001) to support the argument that some paediatricians prefer the term ME (“myalgic encephalitis”). That reference does not mention “myalgic encephalitis”.
The paper refers to the more passive medical approaches being promoted by some groups. Pacing requires more attention than clock or plan-based strategies like graded exercise. It may be argued that pacing, dietary modifications and supportive counselling are not passive, but adaptive. The authors’ selective discussion of the research may mislead the less informed readers while the reinforcement of a particularly negative stereotype could increase stigmatisation, further undermining doctors’ understanding of the illness.]
Baltzan, MA, Elkhouli, O., Creti, L., Bailes, S., Fichten, C., Wolkove, N and Libman, E. Predictors of improvement with continuous positive airway pressure (CPAP) in patients with chronic fatigue syndrome and obstructive sleep apnea. Chest, 2005, 128, 4, 233S-a.
Black, CD and McCully, KK. Time course of exercise induced alterations in daily activity in chronic fatigue syndrome. Dynamic Medicine, 2005 Oct 28. 4, 1, 10.
In a previous study we demonstrated that while people with CFS had lower daily activity levels than control subjects, they were able to increase daily activity via a daily walking program. We reanalyzed our data to determine the time course of activity changes during the walking program. Daily activity assessed via an accelerometer worn at the hip was divided into sleep, active and walking periods. Over the first 4-10 days of walking the subjects with CFS were able to reach the prescribed activity goals each day. After this time, walking and total activity counts decreased. Sedentary controls subjects were able to maintain their daily walking and total activity goals throughout the 4 weeks. Unlike our previous interpretation of the data, we feel this new analysis suggests that CFS patients may develop exercise intolerance as demonstrated by reduced total activity after 4-10 days. The inability to sustain target activity levels, associated with pronounced worsening of symptoms, suggests the subjects with CFS had reached their activity limit.
The text is available at www.dynamic-med.com/content/pdf/1476-5918-4-10.pdf
Brimacombe, M., Lange, G., Bisuchio, K., Ciccone, DS and Natelson, B. Cognitive Function Index for patients with chronic fatigue syndrome. Journal of Chronic Fatigue Syndrome, 2004, 12, 4, 3–23. (Published October 2005).
A comprehensive approach to assessing neuropsychological deficits in CFS patients is developed by assessing cognitive function across a number of domains using a battery of tests, rather than relying on any single instrument. A factor analytic approach was employed to examine the underlying dimensionality of 15 standard cognitive function related test variables in CFS patients. A cognitive function index (CFI) was then developed using appropriately weighted and interpreted factors.
Factor analysis was applied to an initial sample of 65 patients with CFS (CDC criteria ’94, including those with depressive disorders). Eight factors accounting for over 70% of total variation were identified. This factor structure was then independently verified on a separate sample of 124 CFS patients. An overall combined CFS sample of 212 was then used to derive the CFI using an appropriately interpreted and weighted average of the derived factors.
After including age and education as separate factors, the CFI consists of nine factors accounting for 70% of total variation in the overall CFS group. The CFI was not affected by the presence of current psychiatric comorbidity. A cut-off score for cognitive dysfunction was established using the lower quartile value of a group of sedentary controls on the same index.
The CFI will provide a useful summary measure for researchers investigating cognitive function performance in CFS patients. It does not replace existing individual specialized tests.
Goudsmit, E and Stouten, B. Chronic fatigue syndrome: editorial bias in the British Medical Journal. Journal of Chronic Fatigue Syndrome, 2004, 12, 4, 47-59. (Published October 2005).
A literature search identified all papers published on CFS and myalgic encephalomyelitis (ME) in the British Medical Journal between 1995 and 2000. Analysis of the findings revealed a bias towards the views of one school of thought and a lack of papers on the immunological, neurological or virological aspects of CFS. This contrasts with the mainstream American journals which generally covered a much wider range of subjects and views. The authors examine the arguments for and against covert editorial policies, and summarise the results of discussions with the relevant individuals and organisations.
Jones, JF., Kulkarni, PS., Butera, ST and Reeves, WC. GBV-C - a virus without a disease: We cannot give it chronic fatigue syndrome. BMC Infectious Diseases, 2005, 5, 1, 78 [Epub ahead of print]
GBV-C virus is a flavivirus with cell tropism and host defense induction qualities compatible with a role in producing the syndrome. The GBV-C genome is detectable in 4% of the population and 12% of the population is seropositive. The present study evaluated the association between infection with GBV and CFS. We used a commercial EIA to detect antibodies against the GBV-C E2 protein and a quantitative real-time RT-PCR assay to detect active GBV-C infection. Sera were from a case control study of CFS in Atlanta, Georgia. The Fisher's exact two-tailed test was used for statistical analysis.
Two of 12 CFS patients (CDC criteria ’88) and one of 21 controls were seropositive for prior GBV-C infection and one control had viral RNA detected, indicating active infection. The results are not statistically different. We found no evidence that active or past infection with GBV is associated with CFS.
Full text: www.biomedcentral.com/content/pdf/1471-2334-5-78.pdf
Metcalf, LN., McGregor, NR and Roberts, TK. Membrane damaging toxins from coagulase-negative Staphylococcus are associated with self-reported temporomandibular disorder (TMD) in patients with chronic fatigue syndrome. Journal of Chronic Fatigue Syndrome, 2004, 12, 3, 25-43.
This study assessed whether there is any association between membrane damaging toxin production by Staphylococcus spp. and self-reported TMD symptom expression in a group of patients selected to have CFS.
Thirty-three patients with CFS (CDC criteria ’94) and 33 age and sex-matched controls were assessed to evaluate the relationship between carriage of membrane damaging toxin producing staphylococcus, CFS and temporomandibular dysfunction (TMD) symptoms.
The CFS patients had an increased prevalence of face pain (p<.001) and TM joint clicking/locking (p<.007), and the coagulase-negative staphylococcus maximum % β-toxin haemolysis per patient. Both multivariate and univariate analyses revealed an association between the membrane damaging delta-toxin producing CoNS (MDT-CoNS) species per subject and face pain prevalence and intensity within both the CFS patients and the control subjects. No association was found between CoNS toxin production and TMJ clicking/locking.
These data confirm the original observations of the association between MDTCoNS and facial muscle pain. These data also suggest that MDT-CoNS associated facial muscle pain expression represents a distinct clinical entity, which has an increased prevalence in CFS patients.
Randall, DC., Cafferty, FH., Shneerson, JM., Smith, IE, Llewelyn, MB and File, SE. Chronic treatment with modafinil may not be beneficial in patients with chronic fatigue syndrome Journal of Psychopharmacology, 2005, 19, 6, 647-660.
Fourteen patients (7 male, 7 female, 22-63 years), with CFS (without concurrent major depression, significant sleepiness or use of psychoactive medication), completed a double-blind, placebo-controlled, crossover study of the effects of the selective wakefulness-promoting agent, modafinil (200 and 400mg/day). The treatment periods were each 20 days, with washout periods of 2 weeks. The primary aim was to determine effects on cognition and the secondary aim was to determine effects on self-ratings of fatigue, quality of life and mood.
Modafinil had mixed effects in two cognitive tasks. In a test of sustained attention, treatment with 200mg reduced the latency to correctly detect sequences, but 400mg increased the number of missed targets. In a test of spatial planning, the 200mg dose resulted in a slower initial thinking time for the easiest part of the task, whereas 400mg reduced the initial thinking time for the hardest part of the test. Lastly, in a test of mental flexibility and one of motor speed, patients performed worse whilst on modafinil (400mg), compared with the placebo period. No effects were observed on the performance of other psychometric tests or on self-ratings of fatigue, quality of life or mood, but this may have been due to insufficient statistical power. It is discussed whether the limited and mixed cognitive effects that we observed could have occurred by chance, or whether a subgroup of CFS patients with daytime sleepiness would have shown greater benefits.
Richards, RS., McGregor, NR and Roberts, TK. Association between oxidative damage markers and self-reported temporomandibular dysfunction symptoms in patients with chronic fatigue syndrome. Journal of Chronic Fatigue Syndrome, 2004, 12, 3, 45-61.
Full blood counts, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), haematinics and markers for oxidative stress were measured on thirty-three patients diagnosed with CFS (criteria unclear) and twenty-seven age and sex matched controls.
The CFS patients had increased prevalence of symptoms of temporomandibular dysfunction (TMD). Jaw muscle pain was associated with increases in methaemoglobin (p<.002), ferritin (p<.02) and malondialdehyde (p<.007) whilst temporomandibular joint (TMJ) clicking and/or locking was associated with increases in methaemoglobin (p<.001), malondialdehyde (p<.05) and vitamin B12 (p<.02) levels. Multiple regression analysis found methaemoglobin to be the principle component associated with TMD symptoms in the CFS patients. Increases in scalar severity responses to jaw muscle pain and TMJ clicking and/or locking were positively correlated with methaemoglobin by multiple regression. These data indicate that oxidative stress due to excess free radical formation was associated with jaw muscle pain in CFS patients and suggest that these symptoms were likely to be associated with a pathogen-associated aetiology.
Soderlund, A and Malterud, K. Why did I get chronic fatigue syndrome? A qualitative interview study of causal attributions in women patients. Scandinavian Journal of Primary Health Care, 2005, 23, 4, 242-247.
Study of eight patients with CFS (undefined).
Torres-Harding, SR., Jason, LA and Turkoglu, OD. Family medical history of persons with chronic fatigue syndrome. Journal of Chronic Fatigue Syndrome, 2004, 12, 4, 25–35. (Published October 2005).
Little research has examined the family history of persons with CFS, although a few studies have found people with CFS may be more likely to have family members with fatigue or CFS-like conditions, cancers, autoimmune illness, and early parental death. Research into the family history of fatigue, CFS, and other medical or psychiatric illness may help inform the aetiology of this illness. The present investigation examined the occurrence of medical and psychiatric illness in the family history of persons with CFS (n=32, CDC criteria ’94), and then compared these results with the family history of medical illness reported by a control group of persons without fatigue (n=43).
Family medical history data was obtained from questionnaire responses, a medical assessment, and medical records, and were then classified into specific illness categories, using the International Classification of Diseases, Tenth Revision (ICD-10). Family history data was compared among three groups using logistic regression analyses.
Results indicated that persons with CFS were significantly more likely to report a family history of endocrine/metabolic disorders e.g. diabetes and thyroid disorders when compared to the control group. Findings suggest an underlying familial predisposition toward the development of both CFS and endocrine/metabolic disorders. This finding is consistent with the hypothesis that CFS represents a deregulation of the endocrine system.
Van Hoof, E and De Meirleir, K. The influence of chronic fatigue syndrome on the personality profile: a case report. Journal of Chronic Fatigue Syndrome, 2004, 12, 3, 63-71.
Case study of a man who developed CFS (CDC criteria ’94) following long term stress. His treatment included long term antibiotics and graded exercise. His personality profile as measured by the MMPI-2 normalised after recovery, indicating that raised scores on scales for hysteria, depression and hypochondriasis may be related to the presence of physical symptoms.
[Ed. Note: The problems of measuring personality in people with medical conditions using the MMPI has been known for many years, as a result of which that test is now rarely used in medically ill populations.]
Vallings, R. Hypnosis in the management of chronic fatigue syndrome. Journal of Chronic Fatigue Syndrome, 2004, 12, 4, 37–46. (published October 2005).
During the past 30 years hypnosis has become recognised as a useful adjunct to traditional medical therapies, and has become part of mainstream medicine. There are many opportunities for using hypnosis as an adjunctive therapy in the management of CFS, despite some early difficulties. Problems likely to be encountered are discussed and the structure of the hypnosis session is outlined. Suggestions are given for practitioners to construct useful scripts, which can be used to teach self-hypnosis.
Davies, A and Hall, D. ‘‘Contact A Family’’: professionals and parents in partnership. Archives of Disease in Childhood, 2005, 90, 1053–1057.
Review. This paper considers the evidence base on the role of parent organisations in meeting the needs of parents of disabled children for information and support. Having a disabled child is a major cause of stress and has an impact on the health and well-being of the entire family. Current concepts of stress and coping are used to consider coping strategies, including the search for information, the desire to stay in control, and the quest for social support. How and when information and support are provided will impact on how well the family adjust and cope.
Evengård, B., Jacks, A., Pedersen, NL and Sullivan, PF. The epidemiology of chronic fatigue in the Swedish Twin Registry. Psychological Medicine, 2005, 35, 1317-1326.
We screened 31405 individual members of the Swedish Twin Registry (aged 42–64 years) for the symptoms of fatiguing illness via a telephone questionnaire. We refined self-reported symptoms via data from several national registries and from physician review of all available medical records in order to approximate closely the dominant case definition of CFS.
The 6-month prevalence of CFS-like illness was 2·36% and was markedly higher in women than men with no significant association with age or years of education. There was a highly significant association with occupation that disappeared after accounting for gender.
CFS-like illness may be more common that previously acknowledged. There is a marked increase in risk by gender. Previous reports that CFS is more prevalent in individuals in certain occupational categories were not confirmed and may have been due to confounding by gender
[Ed. Note: The researches did not examine their subjects and hence, there is no data on the number who actually had CFS. Findings from this telephone diagnosed sample can not be generalised to clinical samples.]
Furberg, H., Olarte, M., Afari, N., Goldberg, J., Buchwald, D and Sullivan, PF. The prevalence of self-reported chronic fatigue in a U.S. twin registry. Journal of Psychosomatic Research, 2005 59, 5, 283-290.
This study investigated the prevalence and correlates of various definitions of self-reported lifetime fatiguing illness in a U.S. twin registry. Data from 4591 female and male twins from the population-based Mid-Atlantic Twin Registry were available for this study. Variables represent-ting different definitions of lifetime fatiguing illness and personal characteristics were obtained through questionnaires.
Prevalences for different definitions of self-reported lifetime fatigue ranged from 36.7% for any fatigue to 2.7% for chronic fatigue syndrome-like illness. Females were two to three times more likely to report fatigue than males. Gender differences increased as fatigue definitions grew more restrictive. Ages at onset of chronic fatiguing illness were significantly earlier and the number of ancillary symptoms was greater for females than males. People with lifetime fatigue had significantly more compromised functional status than people without lifetime fatigue.
The prevalence of self-reported lifetime fatiguing illness varied widely depending upon how it was defined. Given the debilitating consequences of fatiguing illnesses, the reasons for the female predominance and the earlier onset in women should receive increased research priority.
[Ed. Note: There was no clinical evaluation of participants. The low response rate (31%) may have biased the results.]
Sullivan, PF., Pedersen, NL., Jacks, A and Evengård, B. Chronic fatigue in a population sample: definitions and heterogeneity. Psychological Medicine, 2005, 35, 1337-1348.
We obtained telephone interview data on fatiguing symptoms from 31406 individuals twins in the Swedish Twin Registry aged 42–64 years; 5330 subjects who endorsed fatigue and possessed no exclusionary condition formed the analytic group. We evaluated the definition and classification of CFS-like illness using graphical methods, regression models, and latent class analysis.
Our results raise fundamental questions about the 1994 CDC criteria as (1) there was no empirical support for the requirement of four of eight cardinal CFS symptoms; (2) these eight symptoms were not equivalent in their capacity to predict fatigue; and (3) no combination of symptoms was markedly more heritable. Critically, latent class analysis identified a syndrome strongly resembling CFS-like illness.
Our data are consistent with the ‘existence’ of CFS-like illness although the dominant nosological approach captures population-level variation poorly. We suggest that studying a more parsimonious case definition – impairing chronic fatigue not due to a known cause – would represent a way forward.
[Ed. Note: Of this telephone diagnosed sample, only 14% had a CFS-like illness. Medical records were reviewed but individuals were not checked to see quality of previous examinations, etc.]
Sullivan, PF., Evengård, B., Jacks, A and Pedersen, NL. Twin analyses of chronic fatigue in a Swedish national sample. Psychological Medicine, 2005, 35, 1327-1336.
The authors obtained telephone interview data on current chronic fatigue from 31406 individuals twins in the Swedish Twin Registry (aged 42–64 years, 75·68% response rate), from both members of 12407 pairs and from one member of 6592 pairs. Of the complete pairs, 3269 pairs were monozygotic, 9010 pairs dizygotic, and 128 pairs of unknown zygosity. Structural equation twin modeling was used to estimate the latent genetic architecture of varying definitions of fatiguing illness.
No definition of current fatiguing illness (ranging from any fatigue to CFS-like illness) was strikingly distinctive. Individual-specific effects were the predominant source of variation, followed by modest genetic influences. We could not exclude a small but conceptually important contribution of shared environmental effects.
|
Be sure to see the many other valuable articles at our Main M.E. Home Page