Tag: 2007

Cold pressor pain sensitivity in monozygotic twins discordant for chronic fatigue syndrome

Abstract:

OBJECTIVE: Individuals with chronic fatigue syndrome (CFS) experience many pain symptoms. The present study examined whether pain and fatigue ratings and pain threshold and tolerance levels for cold pain differed between twins with CFS and their cotwins without CFS.

DESIGN: Cotwin control design to assess cold pain sensitivity, pain, and fatigue in monozygotic twins discordant for CFS.

PATIENTS AND SETTING: Fifteen monozygotic twin pairs discordant for CFS recruited from the volunteer Chronic Fatigue Twin Registry at the University of Washington.

RESULTS: Although cold pain threshold and tolerance levels were slightly lower in twins with CFS than their cotwins without CFS, these differences failed to reach statistical significance. Subjective ratings of pain and fatigue at multiple time points during the experimental protocol among twins with CFS were significantly higher than ratings of pain (P = 0.003) and fatigue (P < 0.001) by their cotwins without CFS.

CONCLUSIONS: These results, while preliminary, highlight the perceptual and cognitive components to the pain experience in CFS. Future studies should focus on examining the heritability of pain sensitivity and the underlying mechanisms involved in the perception of pain sensitivity in CFS.

 

Source: Ullrich PM, Afari N, Jacobsen C, Goldberg J, Buchwald D. Cold pressor pain sensitivity in monozygotic twins discordant for chronic fatigue syndrome. Pain Med. 2007 Apr;8(3):216-22. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2957294/ (Full article)

 

The effect of cognitive behaviour therapy for chronic fatigue syndrome on self-reported cognitive impairments and neuropsychological test performance

Abstract:

BACKGROUND: Patients with chronic fatigue syndrome (CFS) often have concentration and memory problems. Neuropsychological test performance is impaired in at least a subgroup of patients with CFS. Cognitive behavioural therapy (CBT) for CFS leads to a reduction in fatigue and disabilities.

AIM: To test the hypothesis that CBT results in a reduction of self-reported cognitive impairment and in an improved neuropsychological test performance.

METHODS: Data of two previous randomised controlled trials were used. One study compared CBT for adult patients with CFS, with two control conditions. The second study compared CBT for adolescent patients with a waiting list condition. Self-reported cognitive impairment was assessed with questionnaires. Information speed was measured with simple and choice reaction time tasks. Adults also completed the symbol digit-modalities task, a measure of complex attentional function.

RESULTS: In both studies, the level of self-reported cognitive impairment decreased significantly more after CBT than in the control conditions. Neuropsychological test performance did not improve.

CONCLUSIONS: CBT leads to a reduction in self-reported cognitive impairment, but not to improved neuropsychological test performance. The findings of this study support the idea that the distorted perception of cognitive processes is more central to CFS than actual cognitive performance.

 

Source: Knoop H, Prins JB, Stulemeijer M, van der Meer JW, Bleijenberg G. The effect of cognitive behaviour therapy for chronic fatigue syndrome on self-reported cognitive impairments and neuropsychological test performance. J Neurol Neurosurg Psychiatry. 2007 Apr;78(4):434-6. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2077788/ (Full article)

 

Sense of effort during a fatiguing exercise protocol in chronic fatigue syndrome

Abstract:

The purpose of this study was to determine whether chronic fatigue syndrome (CFS) subjects would produce greater force production in their matching limb during a fatiguing contralateral limb-matching task of the elbow flexors, compared with healthy, matched controls.

Eight CFS subjects and 8 healthy, matched control subjects participated in a fatiguing task that consisted of intermittent submaximal contractions (30% maximal voluntary contraction) of the nondominant arm performed over a 45 min duration. Each minute, the subject attempted to match the force of the nondominant arm with their dominant arm (without visual feedback for the dominant arm).

Results showed that average matching force and ratings of perceived effort values were significantly higher in the CFS group during the fatiguing task (P = 0.04, P = 0.02, respectively). This study demonstrated objectively that CFS subjects experienced a greater sense of effort in the elbow flexors while performing a fatiguing task.

 

Source: Wallman KE, Sacco P. Sense of effort during a fatiguing exercise protocol in chronic fatigue syndrome. Res Sports Med. 2007 Jan-Mar;15(1):47-59. https://www.ncbi.nlm.nih.gov/pubmed/17365951

 

Infection and vaccination in chronic fatigue syndrome: myth or reality?

Abstract:

Chronic fatigue syndrome (CFS) is characterized by severe disabling fatigue lasting for more than 6 months associated with physical and mental disturbances such as headache, arthralgia, myalgia, memory impairment, sore throat and tender lymph nodes. The exact pathogenesis is still unknown. Several models were proposed to explain its etiology including chronic infection, endocrine dysfunction, autonomic imbalance, depression, decreased immunity states and an aberrant reaction to infection. No convincing evidence was found to support any of the suggested pathogenic mechanisms.

The current concept is that CFS pathogenesis is a multi factorial condition in which an infective agent cause an aberrant immune response characterized by a shift to Th-2 dominant response. When the response fails to be switched-off, a chronic immune activation occurs and clinically expressed as the symptomatology of CFS. Vaccinations are used in order to stimulate the immune system to induce a persistent immunity against the favorable antigens.

Several syndromes that contain chronic fatigue as one of their symptoms, such as “Gulf war syndrome” and macrophagic myofasciitis were related to vaccinations. Can vaccinations induce the aberrant immune response of CFS? Little is known about this issue. There are some reports on CFS occurring after vaccination, but few prospective and retrospective studies failed to find such an association. A working group of the Canadian Laboratory Center for Disease Control (LCDC) that was founded in order to examine the suspected association between CFS and vaccinations concluded that there is no evidence that relates CFS to vaccination.

Further studies are requested to examine this issue since it is very conceivable that if infection can lead to CFS, vaccination may also lead to it in the same immune-mediated pathogenesis.

 

Source: Appel S, Chapman J, Shoenfeld Y. Infection and vaccination in chronic fatigue syndrome: myth or reality? Autoimmunity. 2007 Feb;40(1):48-53. https://www.ncbi.nlm.nih.gov/pubmed/17364497

 

Exercise testing in children and adolescents with chronic fatigue syndrome

Abstract:

The objective of this study was to evaluate exercise capacity in children and adolescents diagnosed with Chronic Fatigue Syndrome (CFS). We examined 20 patients (12 girls and 8 boys; mean age 14.9 +/- 3.7 years) diagnosed with CFS.

Exercise capacity was measured using a maximal exercise test on a bicycle ergometer and an expired gas analysis system. Fatigue was assessed using a questionnaire and a daily activity diary was used to describe activities for three days. Z-scores were calculated using age- and sex-matched reference values. Z-scores in children and adolescents with CFS were – 0.33 +/- 1.0 (p = 0.17) for peak oxygen uptake, – 1.13 +/- 1.41 (p = 0.002) for relative peak oxygen uptake [ml/kg/min] and – 0.93 +/- 1.29 (p = 0.07) for maximal work load. Both heart rate and blood pressure at peak performance were significantly reduced compared to reference values.

Fatigue levels were significantly positively associated with age and negatively with blood pressure at peak exercise (p < 0.05). In conclusion maximum exercise testing was feasible in young people with CFS. Maximal exercise capacity was only reduced in a minority of the patients and was related to current physical activity levels.

 

Source: Takken T, Henneken T, van de Putte E, Helders P, Engelbert R. Exercise testing in children and adolescents with chronic fatigue syndrome. Int J Sports Med. 2007 Jul;28(7):580-4. Epub 2007 Mar 15. https://www.ncbi.nlm.nih.gov/pubmed/17357961

 

Personality and chronic fatigue syndrome: methodological and conceptual issues

Abstract:

Among clinical psychologists, consulting physicians, scientific researchers and society in general an image has emerged of patients with chronic fatigue syndrome (CFS) as perfectionist, conscientious, hardworking, somewhat neurotic and introverted individuals with high personal standards, a great desire to be socially accepted and with a history of continuously pushing themselves past their limits.

The aim of this article is to (a) give a concise review of the main recent studies on personality and CFS, (b) address the major methodological problems in the study of personality in CFS and (c) discuss some of the conceptual assumptions that seem to limit the research on personality and CFS.

The results of the reviewed studies range from no evidence of major differences between the personalities of patients with CFS and controls, to evidence of severe psychopathology and personality disorder in patients with CFS. Although personality seems to play a role in CFS, it is difficult to draw general conclusions on the relation between personality and CFS. It is argued that this is partially due to the diversity and heterogeneity in study methods, patient populations, control groups and CFS case definitions.

Personality should be regarded as an important factor to be studied in CFS. However, additional studies are needed, not focusing exclusively on personality disorder, or personality considered on a general trait level. In recent developments in personality research, the continually evolving life narrative that makes sense of, and gives direction to, an individual’s life is also regarded as an important aspect of personality. New insights into personality and CFS might be gained by systematically studying the self-narratives of patients with the syndrome.

 

Source: van Geelen SM, Sinnema G, Hermans HJ, Kuis W. Personality and chronic fatigue syndrome: methodological and conceptual issues. Clin Psychol Rev. 2007 Dec;27(8):885-903. Epub 2007 Jan 27. https://www.ncbi.nlm.nih.gov/pubmed/17350740

 

Can submaximal exercise variables predict peak exercise performance in women with chronic fatigue syndrome?

Abstract:

This study aimed at examining whether physiological exercise variables at the submaximal level, defined as 75% of the age-predicted target heart rate, are able to predict peak exercise performance in women with chronic fatigue syndrome (CFS) (n=222). Subjects performed a bicycle ergometric test against a graded increase in workload until exhaustion with continuous monitoring of electrocardiographic and ventilatory variables. Oxygen uptake at the submaximal level (VO2SUBMAX) correlated strongly with peak oxygen uptake (VO2PEAK) (r=0.70). For the prediction of VO2PEAK, linear regression analysis determined the line of best fit as: VO2PEAK=0.95xVO2SUBMAX+372.3. Using this equation, the mean error in the prediction was 14.6+/-11.2% (range 0.1-63.7%). It is concluded that the prediction of VO2PEAK based on VO2SUBMAX might be useful for analyzing group differences or treatment effects but not for individual (clinical) purposes.

Source: Nijs J, Demol S, Wallman K. Can submaximal exercise variables predict peak exercise performance in women with chronic fatigue syndrome? Arch Med Res. 2007 Apr;38(3):350-3. Epub 2007 Jan 30. https://www.ncbi.nlm.nih.gov/pubmed/17350488

Incidence, prognosis, and risk factors for fatigue and chronic fatigue syndrome in adolescents: a prospective community study

Abstract:

OBJECTIVE: The objective of this study was to describe the incidence, prevalence, risk factors, and prognosis of fatigue, chronic fatigue, and chronic fatigue syndrome in 11- to 15-year-olds.

METHODS: A random general population sample (n = 842) of British adolescents and their parents were assessed at baseline and 4 to 6 months later. The main outcomes were fatigue, chronic fatigue, and chronic fatigue syndrome, operationally defined.

RESULTS: The incidence over 4 to 6 months was 30.3% for fatigue, 1.1% for chronic fatigue, and 0.5% for chronic fatigue syndrome. The point prevalence was 34.1% and 38.1% for fatigue, 0.4% and 1.1% for chronic fatigue, and 0.1% and 0.5% for chronic fatigue syndrome at time 1 and time 2, respectively. Of participants who were fatigued at time 1, 53% remained fatigued at time 2. The 3 cases of chronic fatigue and 1 case of chronic fatigue syndrome at time 1 had recovered by time 2. Higher risk for development of chronic fatigue at time 2 was associated with time 1 anxiety or depression, conduct disorder, and maternal distress; in multivariate analysis, baseline anxiety or depression remained a significant predictor of chronic fatigue. Increased risk for development of fatigue at time 2 was associated with time 1 anxiety or depression, conduct disorder, and older age; in multivariate analyses, these factors and female gender all were significant predictors of fatigue.

CONCLUSIONS: The incidence rates for chronic fatigue and chronic fatigue syndrome in this adolescent sample were relatively high, but the prognosis for these conditions was good. This prospective study provides evidence for an association between emotional/behavioral problems and subsequent onset of fatigue/chronic fatigue.

 

Source: Rimes KA, Goodman R, Hotopf M, Wessely S, Meltzer H, Chalder T. Incidence, prognosis, and risk factors for fatigue and chronic fatigue syndrome in adolescents: a prospective community study. Pediatrics. 2007 Mar;119(3):e603-9. https://www.ncbi.nlm.nih.gov/pubmed/17332180

 

Defining the occurrence and influence of alpha-delta sleep in chronic fatigue syndrome

Abstract:

BACKGROUND: Patients with chronic fatigue syndrome (CFS) present a disordered sleep pattern and frequently undergo polysomnography to exclude a primary sleep disorder. Such studies have shown reduced sleep efficiency, a reduction of deep sleep, prolonged sleep initiation, and alpha-wave intrusion during deep sleep. Deregulation of the 2-5A synthetase/RNase L antiviral pathway and a potential acquired channelopathy are also found in a subset of CFS patients and could lead to sleep disturbances. This article compiles a large sleep study database on CFS patients and correlates these data with a limited number of immune parameters as it has been thought that RNase L could be associated with these sleep disturbances.

METHODS: Forty-eight patients who fulfilled 1994 Centers for Disease Control and Prevention criteria for CFS underwent extensive medical evaluation, routine laboratory testing, and a structured psychiatric interview. Subjects then completed a complaint checklist and a two-night polysomnographic investigation. RNase L analysis was performed by gel electrophoresis using a radiolabeled 2′,5′-oligoadenylate trimer. Basic descriptive statistical parameters were calculated.

RESULTS: Patients experienced a prolonged sleep latency, showed a low sleep efficiency index, and had a low percentage of slow wave sleep. The present alpha-delta intrusion correlated with anxiety; no correlations appeared, however, between alpha-delta sleep and immunologic parameters, including RNase L.

CONCLUSIONS: The main findings are 1) validation of sleep latency problems and other sleep disturbances as already suggested by several authors; 2) alpha-delta intrusion seems associated with anxiety; and 3) elevated RNase L did not correlate with alpha-delta sleep.

 

Source: Van Hoof E, De Becker P, Lapp C, Cluydts R, De Meirleir K. Defining the occurrence and influence of alpha-delta sleep in chronic fatigue syndrome. Am J Med Sci. 2007 Feb;333(2):78-84. https://www.ncbi.nlm.nih.gov/pubmed/17301585

 

Fibromylagia, chronic fatigue, and adult attention deficit hyperactivity disorder in the adult: a case study

Abstract:

Adult attention deficit hyperactivity disorder (ADHD) may share common features with fibromyalgia syndrome (FMS) and chronic fatigue syndrome(CFS). In an outpatient psychiatric clinic, a number of adult patients who presented primarily with symptoms of ADHD, predominately inattentive type, also reported unexplained fatigue, widespread musculoskeletal pain or a pre-existing diagnosis of CFS or FMS.

As expected, ADHD pharmacotherapy usually attenuated the core ADHD symptoms of inattention, distractibility, hyperactivity, and impulsivity. Less expected was the observation that some patients also reported amelioration of pain and fatigue symptoms. The utility of ADHD medications in FMS and CFS states may be their innate arousal and enhanced filtering properties.

This model supposes that FMS and CFS are central processing problems rather than peripheral disorders of muscles and joints.

 

Source: Young JL, Redmond JC. Fibromylagia, chronic fatigue, and adult attention deficit hyperactivity disorder in the adult: a case study. Psychopharmacol Bull. 2007;40(1):118-26. https://www.ncbi.nlm.nih.gov/pubmed/17285103