2010 – Page 10 – American ME and CFS Society

Nitric oxide metabolite production during exercise in chronic fatigue syndrome: a case-control study

Abstract:

BACKGROUND: Chronic fatigue syndrome (CFS) is a disabling illness of unknown etiology that is characterized by fatigue associated with a reduced ability to work, lasting for more than 6 months, and accompanied by a specific set of symptoms. The diagnosis remains difficult because of the absence of laboratory tests and is, therefore, made largely on the basis of the symptoms reported by the patient. The aim of this study was to analyze differences in blood nitrate levels in CFS patients and a matched control group after a physical exercise test.

METHODS: Forty-four consecutive female patients with CFS and 25 healthy women performed an exercise test using a cycle ergometer with monitoring of cardiopulmonary response. Blood samples were obtained for biochemical analyses of glucose, lactate, and nitrates at the beginning (under resting conditions) and after the maximal and supramaximal tests.

RESULTS: Plasma nitrates differed between the groups, with higher values in the CFS group (F = 6.93, p = 0.003). Nitrate concentration increased in relation to workload and reached higher values in the CFS group, the maximum difference with respect to the control group being 295% (t = 4.88, p < 0.001).

CONCLUSIONS: The main result of the present study is that nitric oxide (NO) metabolites (nitrates) showed a much higher increase after a maximal physical test in CFS patients than in a group of matched subjects. This combination (exercise plus NO response evaluation) may be useful in the assessment of CFS.

Source: Suárez A, Guillamó E, Roig T, Blázquez A, Alegre J, Bermúdez J, Ventura JL, García-Quintana AM, Comella A, Segura R, Javierre C. Nitric oxide metabolite production during exercise in chronic fatigue syndrome: a case-control study. J Womens Health (Larchmt). 2010 Jun;19(6):1073-7. doi: 10.1089/jwh.2008.1255. https://www.ncbi.nlm.nih.gov/pubmed/20469961

Comment on “Detection of an infectious retrovirus, XMRV, in blood cells of patients with chronic fatigue syndrome”

Abstract:

Lombardi et al. (Reports, 23 October 2009, p. 585) reported a significant association between the human retrovirus XMRV and chronic fatigue syndrome (CFS). However, the cases with CFS and the control subjects in their study are poorly described and unlikely to be representative. Independent replication is a critical first step before accepting the validity of this finding.

Comment on: Detection of an infectious retrovirus, XMRV, in blood cells of patients with chronic fatigue syndrome. [Science. 2009]

You can read the full comment here: http://science.sciencemag.org/content/328/5980/825.2.full

Source: Lloyd A, White P, Wessely S, Sharpe M, Buchwald D. Comment on “Detection of an infectious retrovirus, XMRV, in blood cells of patients with chronic fatigue syndrome”. Science. 2010 May 14;328(5980):825; author reply 825. doi: 10.1126/science.1183706. http://science.sciencemag.org/content/328/5980/825.2.full (Full article)

Comment on “Detection of an infectious retrovirus, XMRV, in blood cells of patients with chronic fatigue syndrome”

Abstract:

Lombardi et al. (Reports, 23 October 2009, p. 585) reported detection of the human gammaretrovirus XMRV in the blood cells of patients with chronic fatigue syndrome (CFS). However, the patient description provided was incomplete. The inclusion of patients from a “CFS outbreak” previously linked with a viral infection, without confirmation in sporadic CFS cases, casts doubt on the role of XMRV in the pathogenesis of CFS.

You can read the full comment here: http://science.sciencemag.org/content/328/5980/825.3.full

Comment on: Detection of an infectious retrovirus, XMRV, in blood cells of patients with chronic fatigue syndrome. [Science. 2009]

Source: van der Meer JW, Netea MG, Galama JM, van Kuppeveld FJ. Comment on “Detection of an infectious retrovirus, XMRV, in blood cells of patients with chronic fatigue syndrome”. Science. 2010 May 14;328(5980):825; author reply 825. doi: 10.1126/science.1183906. http://science.sciencemag.org/content/328/5980/825.3.long (Full article)

EEG findings in burnout patients

Abstract:

The concept of burnout remains enigmatic since it is only determined by behavioral characteristics. Moreover, the differential diagnosis with depression and chronic fatigue syndrome is difficult.

EEG-related variables in 13 patients diagnosed with burnout syndrome were compared with 13 healthy comparison subjects in order to explore the existence of neurobiological markers for burnout.

Burnout patients showed reduced P300 amplitude, a lower alpha peak frequency and reduced beta power. These EEG-related differences in burnout patients differ from those described in the literature in depression and chronic fatigue patients. Our preliminary findings suggest that burnout might be considered as a separate clinical syndrome.

Source: van Luijtelaar G, Verbraak M, van den Bunt M, Keijsers G, Arns M. EEG findings in burnout patients. J Neuropsychiatry Clin Neurosci. 2010 Spring;22(2):208-17. doi: 10.1176/appi.neuropsych.22.2.208. https://www.ncbi.nlm.nih.gov/pubmed/20463115

Impaired sleep in chronic fatigue syndrome: how is it best measured?

Abstract:

The goal was to examine comparative efficacy of polysomnography, actigraphy, and self-report in evaluating the sleep/wake experience of individuals with chronic fatigue syndrome (CFS). Sleep parameters were evaluated by the three measurement modalities for the same night in 49 participants with CFS. Psychological and daytime functioning were measured by self-report. Results indicate that: (a) objectively measured nocturnal sleep time effectively approximated subjective experience although nocturnal wakefulness did not; (b) total sleep time and sleep efficiency differentiated individuals with and without insomnia complaints; (c) daytime sleepiness, fatigue, and non-refreshing sleep were not reflected by the objective sleep-related measures (polysomnography and actigraphy).

Source: Creti L, Libman E, Baltzan M, Rizzo D, Bailes S, Fichten CS. Impaired sleep in chronic fatigue syndrome: how is it best measured? J Health Psychol. 2010 May;15(4):596-607. Doi: 10.1177/1359105309355336. https://www.ncbi.nlm.nih.gov/pubmed/20460416

Exercise tolerance testing in a prospective cohort of adolescents with chronic fatigue syndrome and recovered controls following infectious mononucleosis

Abstract:

OBJECTIVE: Six months after acute infectious mononucleosis (IM), 13% of adolescents meet criteria for chronic fatigue syndrome (CFS). We measured exercise tolerance in adolescents with CFS and control subjects 6 months after IM.

STUDY DESIGN: Twenty-one adolescents with CFS 6 months after IM and 21 recovered control subjects performed a maximal incremental exercise tolerance test with breath-by-breath gas analysis. Values expressed are mean+/-standard deviation.

RESULTS: The adolescents diagnosed with CFS and control subjects did not differ in age, weight, body mass index, or peak work capacity. Lower oxygen consumption peak percent of predicted was seen in adolescents with CFS compared with control subjects (CFS 99.3+/-16.6 vs control subject 110.7+/-19.9, P=.05). Peak oxygen pulse also was lower in adolescents with CFS compared with recovered control subjects (CFS 12.4+/-2.9 vs control subjects 14.9+/-4.3, P=.03).

CONCLUSIONS: Adolescents with CFS 6 months after IM have a lower degree of fitness and efficiency of exercise than recovered adolescents. Whether these abnormal exercise findings are a cause or effect of CFS is unknown. IM can lead to both fatigue and measurable changes in exercise testing in a subset of adolescents.

Source: Katz BZ, Boas S, Shiraishi Y, Mears CJ, Taylor R. Exercise tolerance testing in a prospective cohort of adolescents with chronic fatigue syndrome and recovered controls following infectious mononucleosis. J Pediatr. 2010 Sep;157(3):468-72, 472.e1. doi: 10.1016/j.jpeds.2010.03.025. Epub 2010 May 6. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2975670/ (Full article)

Nicotinamide adenine dinucleotide (NADH) in patients with chronic fatigue syndrome

Abstract:

BACKGROUND: Nicotinamide adenine dinucleotide (NADH) may be depleted in chronic fatigue syndrome (SFC). The purpose of the study was to evaluate the efficacy of supplementation with NADH in these patients.

MATERIAL AND METHODS: A double blind, placebo controlled, 3 month long clinical trial was conducted. The patients were randomized to oral NADH oral 20mg or placebo during the first two months. The intensity of the fatigue, functional performance, mood state, functional impact of the fatigue, quality of life, sleep quality, exercise capacity and functional reserve as well as the investigator’s and patient’s opinion on the efficacy of the intervention prior to and at 30, 60 and 90 days of the onset of the treatment were evaluated. A stress test was performed in the baseline visit and at 60 days (last day of the double blind treatment).

RESULTS: A total of 86 patients, 77 of whom completed the study (mean age, 47 years, 72 women) were enrolled. No significant differences were found in most of the variable studied at the end of the study. Administration of NADH was associated to a decrease in anxiety condition of -1.0 points (p<0.05) and of -0.2 points (p=NS) in the placebo assigned group. Maximum heart rate after the stress test decreased a mean of -8.1l/min (p<0.05) in the NADH group and increased by +1.7l/min in the placebo group (p=0.73). No differences were found in the perception of efficacy with NADH and placebo, by the investigator and patients.

CONCLUSIONS: Administration of oral NADH was associated to a decrease in anxiety and maximum heart rate, after a stress test in patients with CFS. On the contrary, this treatment did not modify other clinical variables and the global functional performance.

Source: Alegre J, Rosés JM, Javierre C, Ruiz-Baqués A, Segundo MJ, de Sevilla TF. Nicotinamide adenine dinucleotide (NADH) in patients with chronic fatigue syndrome. Rev Clin Esp. 2010 Jun;210(6):284-8. doi: 10.1016/j.rce.2009.09.015. Epub 2010 May 5. [Article in Spanish] https://www.ncbi.nlm.nih.gov/pubmed/20447621

A formal analysis of cytokine networks in chronic fatigue syndrome

Abstract:

Chronic Fatigue Syndrome (CFS) is a complex illness affecting 4 million Americans for which no characteristic lesion has been identified. Instead of searching for a deficiency in any single marker, we propose that CFS is associated with a profound imbalance in the regulation of immune function forcing a departure from standard pre-programmed responses.

To identify these imbalances we apply network analysis to the co-expression of 16 cytokines in CFS subjects and healthy controls. Concentrations of IL-1a, 1b, 2, 4, 5, 6, 8, 10, 12, 13, 15, 17 and 23, IFN-γ, lymphotoxin-α (LT-α) and TNF-α were measured in the plasma of 40 female CFS and 59 case-matched controls. Cytokine co-expression networks were constructed from the pair-wise mutual information (MI) patterns found within each subject group.

These networks differed in topology significantly more than expected by chance with the CFS network being more hub-like in design. Analysis of local modularity isolated statistically distinct cytokine communities recognizable as pre-programmed immune functional components.

These showed highly attenuated Th1 and Th17 immune responses in CFS. High Th2 marker expression but weak interaction patterns pointed to an established Th2 inflammatory milieu. Similarly, altered associations in CFS provided indirect evidence of diminished NK cell responsiveness to IL-12 and LT-α stimulus.

These observations are consistent with several processes active in latent viral infection and would not have been uncovered by assessing marker expression alone. Furthermore this analysis identifies key sub-networks such as IL-2:IFN-γ:TNF-α that might be targeted in restoring normal immune function.

Comment in: Letter to the editor re: “A formal analysis of cytokine networks in chronic fatigue syndrome” by Broderick et al. [Brain Behav Immun. 2010]

Source: Broderick G, Fuite J, Kreitz A, Vernon SD, Klimas N, Fletcher MA. A formal analysis of cytokine networks in chronic fatigue syndrome. Brain Behav Immun. 2010 Oct;24(7):1209-17. doi: 10.1016/j.bbi.2010.04.012. Epub 2010 May 4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2939140/ (Full article)

Is the International Physical Activity Questionnaire-short form (IPAQ-SF) valid for assessing physical activity in Chronic Fatigue Syndrome?

Abstract:

PURPOSE: To evaluate the criterion validity and internal consistency of the International Physical Activity Questionnaire-short form (IPAQ-sf) in Chronic Fatigue Syndrome (CFS) patients.

METHOD: Fifty-six CFS patients completed the IPAQ-sf after they wore a tri-axial accelerometer and filled out activity diaries during 1 week. Spearman rank correlation coefficients and Cronbach’s Alpha were calculated.

RESULTS: The IPAQ-sf correlated significantly with the energy expenditure and Metabolic Equivalents (METs) minutes spent moderately to vigorously active following the activity diary and accelerometer. These correlation coefficients were however low (r varying between 0.282 and 0.426) and rather irrelevant, since CFS patients hardly reach moderate or vigorous activity levels. Internal consistency between the three subitems used for the total score of the IPAQ-sf was 0.337.

CONCLUSION: The observed associations between the IPAQ-sf data and the data obtained from the accelerometer (gold standard) and the diaries were too low to be in support of the use of the IPAQ-sf in patients with CFS. The IPAQ-sf does not seem an appropriate tool to assess physical activity in CFS patients. Further study is required to seek for a valid, practical and affordable tool.

Source: Meeus M, Van Eupen I, Willems J, Kos D, Nijs J. Is the International Physical Activity Questionnaire-short form (IPAQ-SF) valid for assessing physical activity in Chronic Fatigue Syndrome? Disabil Rehabil. 2011;33(1):9-16. doi: 10.3109/09638288.2010.483307. Epub 2010 May 6. https://www.ncbi.nlm.nih.gov/pubmed/20446802

Unravelling the nature of postexertional malaise in myalgic encephalomyelitis/chronic fatigue syndrome: the role of elastase, complement C4a and interleukin-1beta

Abstract:

OBJECTIVES: Too vigorous exercise or activity increase frequently triggers postexertional malaise in people with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), a primary characteristic evident in up to 95% of people with ME/CFS. The present study aimed at examining whether two different types of exercise results in changes in health status, circulating elastase activity, interleukin (IL)-1beta and complement C4a levels.

DESIGN: Comparative experimental design.

SETTING: University.

SUBJECTS: Twenty-two women with ME/CFS and 22 healthy sedentary controls.

INTERVENTIONS: participants were subjected to a submaximal exercise (day 8) and a self-paced, physiologically limited exercise (day 16). Each bout of exercise was preceded and followed by blood sampling, actigraphy and assessment of their health status.

RESULTS: Both submaximal exercise and self-paced, physiologically limited exercise resulted in postexertional malaise in people with ME/CFS. However, neither exercise bout altered elastase activity, IL-1beta or complement C4a split product levels in people with ME/CFS or healthy sedentary control subjects (P > 0.05). Postexercise complement C4a level was identified as a clinically important biomarker for postexertional malaise in people with ME/CFS.

CONCLUSIONS: Submaximal exercise as well as self-paced, physiologically limited exercise triggers postexertional malaise in people with ME/CFS, but neither types of exercise alter acute circulating levels of IL-1beta, complement C4a split product or elastase activity. Further studying of immune alterations in relation to postexertional malaise in people with ME/CFS using multiple measurement points postexercise is required.

Source: Nijs J, Van Oosterwijck J, Meeus M, Lambrecht L, Metzger K, Frémont M, Paul L. Unravelling the nature of postexertional malaise in myalgic encephalomyelitis/chronic fatigue syndrome: the role of elastase, complement C4a and interleukin-1beta. J Intern Med. 2010 Apr;267(4):418-35. doi: 10.1111/j.1365-2796.2009.02178.x. http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2796.2009.02178.x/full (Full article)