Tag: exercise

Cerebral Blood Flow and Heart Rate Variability in Chronic Fatigue Syndrome: A Randomized Cross-Over Study

Abstract:

BACKGROUND: Pain, fatigue, and concentration difficulties are typical features of chronic fatigue syndrome (CFS). The exact underlying mechanisms of these symptoms are still unknown, but available evidence suggests an important role for impaired pain modulation. As evidence also suggests that pain modulation is related to cardiovascular mechanisms, it seems logical to investigate whether cerebral blood flow (CBF) and heart rate variability (HRV) are altered in these patients.

OBJECTIVES: We aimed to investigate the role of the cardiovascular system in pain modulation and symptoms of CFS; the response of CBF and HRV to physical stress and their relation to the change in temporal summation (TS) of pressure pain and self-reported symptoms was evaluated.

STUDY DESIGN: A controlled, randomized cross-over trial.

SETTING: University Hospital Brussels.

METHODS: Twenty CFS patients and 20 sedentary healthy controls were included in this study. In both of the groups, the change in TS of pressure pain, CBF (using transcranial Doppler), and HRV (using finger plethysmography) was examined during physical and emotional stress (to control for potential bias), as well as their association mutually and with self-reported symptoms of pain, fatigue, and concentrations difficulties.

RESULTS: There was no significant interaction or group (F-values ranging from .100 to 1.862, P-values ranging from .754 to .181) effect in CBF or HRV parameters. HRV and CBF did change during physical exercise, but the changes did not differ between patients and controls. While pain scores during TS at the trapezius site reduced in the control group after the physical exercise protocol (P = .037), they did not change in the CFS group (P = .108), suggesting impaired pain modulation. There were no significant correlations between CBF, HRV, TS, and self-reported symptoms (all P-values of correlation analyses > .01).

LIMITATIONS: Although effect sizes were medium to large, the study sample was relatively low. Also, the mild nature of the exercise bout is discussable. Nonetheless, this mild exercise was able to provoke endogenous pain modulation in the control group, which endorsed a proper execution of the cycling exercise. Moreover, mild exercises are more applicable to daily physical activities in CFS patients than vigorous exercises.

CONCLUSION: These results seem to refute the previously suggested alterations of CBF/HRV in CFS patients. These cardiovascular parameters appear not to explain pain before, during, and following exercise.

Source: Malfliet A, Pas R, Brouns R, De Win J, Hatem SM, Meeus M, Ickmans K, van Hooff RJ, Nijs J. Cerebral Blood Flow and Heart Rate Variability in Chronic Fatigue Syndrome: A Randomized Cross-Over Study. Pain Physician. 2018 Jan;21(1):E13-E24. https://www.ncbi.nlm.nih.gov/pubmed/29357332 Full article can be viewed as a PDF here: http://www.painphysicianjournal.com/current/pdf?article=NTAwOA%3D%3D&journal=109

Cytokine responses to exercise and activity in patients with chronic fatigue syndrome: Case control study

Abstract:

Chronic fatigue syndrome (CFS) is characterized by fatigue after exertion. A systematic review suggested that transforming growth factor beta (TGF-β) concentrations are often elevated in cases of CFS when compared to healthy controls. This study attempted to replicate this finding, and investigate whether post-exertional symptoms were associated with altered cytokine protein concentrations and their RNA in CFS patients. Twenty-four patients fulfilling Centers for Disease Control criteria for CFS, but with no comorbid psychiatric disorders, were recruited from two CFS clinics in London, UK. Twenty-one healthy, sedentary controls were matched by gender, age, and other variables. Circulating proteins and RNA were measured for TGF-β, TNF, IL-8, IL-6 and IL-1β.

We measured six further cytokine protein concentrations (IL-2, IL-4, IL-5, IL-10, IL-12p70, and IFN-γ). Measures were taken at rest, and before and after both commuting and aerobic exercise. CFS cases had higher TGF-β protein levels compared to controls at rest (median (quartiles) = 43.9 (19.2, 61.8) versus 18.9 (16.1, 30.0) ng/ml) (p = 0.003), and consistently so over a nine-day period. However, this was a spurious finding due to variation between different assay batches.

There were no differences between groups in changes to TGF-β protein concentrations after either commuting or exercise. All other cytokine protein and RNA levels were similar between cases and controls. Post-exertional symptoms and perceived effort were not associated with any increased cytokines. We were unable to replicate previously found elevations in circulating cytokine concentrations, suggesting that elevated circulating cytokines are not important in the pathophysiology of CFS.

This article is protected by copyright. All rights reserved.

© 2017 British Society for Immunology

Source: Clark LV, Buckland M, Murphy G, Taylor N, Vleck V, Mein C, Wozniak E, Smuk M, White PD. Cytokine responses to exercise and activity in patients with chronic fatigue syndrome: Case control study .Clin Exp Immunol. 2017 Aug 5. doi: 10.1111/cei.13023. [Epub ahead of print] https://www.ncbi.nlm.nih.gov/pubmed/28779554

Pacing, Conventional Physical Activity and Active Video Games to Increase Physical Activity for Adults with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Protocol for a Pilot Randomized Controlled Trial

Abstract:

BACKGROUND: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a serious illness of biological origin characterized by profound physical and cognitive exhaustion and postexertion malaise. Pacing is a common strategy used to manage available energy and complete activities of daily living; yet little research has investigated this as a strategy to increase physical activity levels. Typically, people living with ME/CFS are faced by unique barriers to physical activity participation and are less physically active than healthy peers. As such they are at increased risk of physical inactivity-related health consequences. Active video games may be a feasible and acceptable avenue to deliver physical activity intervention by overcoming many of the reported barriers to participation.

OBJECTIVE: The primary objective of this pilot study is to determine the feasibility and acceptability of active video games to increase physical activity levels of people with ME/CFS. The secondary aims are to explore the preliminary effectiveness of pacing and active video gaming to pacing alone and pacing plus conventional physical activity to increase the physical activity levels of adults with ME/CFS and explore the relationship between physical activity and cumulative inflammatory load (allostatic load).

METHODS: This study will use a mixed method design, with a 3-arm pilot randomized controlled trial, exit interviews, and collection of feasibility and process data. A total of 30 adults with ME/CFS will be randomized to receive either (1) pacing, (2) pacing and conventional physical activity, or (3) pacing and active video gaming. The intervention duration will be 6 months, and participants will be followed up for 6 months postintervention completion. The intervention will be conducted in the participant’s home, and activity intensity will be determined by continuously monitored heart rate and ratings of perceived exertion. Feasibility and acceptability and process data will be collected during and at the end of the intervention. Health-related outcomes (eg, physical activity, blood samples, quality of life, and functioning) will be collected at baseline, end of intervention, and 6 months after intervention completion.

RESULTS: This protocol was developed after 6 months of extensive stakeholder and community consultation. Enrollment began in January 2017; as of publication, 12 participants were enrolled. Baseline testing is scheduled to commence in mid-2017.

CONCLUSIONS: This pilot study will provide essential feasibility and acceptability data which will guide the use of active video games for people with ME/CFS to increase their physical activity levels. Physical activity promotion in this clinical population has been poorly and under-researched, and any exploration of alternative physical activity options for this population is much needed.

TRIAL REGISTRATION: Australia New Zealand Clinical Trials Registry: ACTRN12616000285459; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=370224 (Archived by WebCite at http://www.webcitation.org/6qgOLhWWf).

Source: Ferrar KE, Smith AE, Davison K. Pacing, Conventional Physical Activity and Active Video Games to Increase Physical Activity for Adults with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Protocol for a Pilot Randomized Controlled Trial. JMIR Res Protoc. 2017 Aug 1;6(8):e117. doi: 10.2196/resprot.7242. http://www.researchprotocols.org/2017/8/e117/ (Full article)

High flow variant postural orthostatic tachycardia syndrome amplifies the cardiac output response to exercise in adolescents

Abstract:

Postural orthostatic tachycardia syndrome (POTS) is characterized by chronic fatigue and dizziness and affected individuals by definition have orthostatic intolerance and tachycardia. There is considerable overlap of symptoms in patients with POTS and chronic fatigue syndrome (CFS), prompting speculation that POTS is akin to a deconditioned state.

We previously showed that adolescents with postural orthostatic tachycardia syndrome (POTS) have excessive heart rate (HR) during, and slower HR recovery after, exercise – hallmarks of deconditioning. We also noted exaggerated cardiac output during exercise which led us to hypothesize that tachycardia could be a manifestation of a high output state rather than a consequence of deconditioning.

We audited records of adolescents presenting with long-standing history of any mix of fatigue, dizziness, nausea, who underwent both head-up tilt table test and maximal exercise testing with measurement of cardiac output at rest plus 2-3 levels of exercise, and determined the cardiac output () versus oxygen uptake () relationship. Subjects with chronic fatigue were diagnosed with POTS if their HR rose ≥40 beat·min(-1) with head-up tilt.

Among 107 POTS patients the distribution of slopes for the , relationship was skewed toward higher slopes but showed two peaks with a split at ~7.0 L·min(-1) per L·min(-1), designated as normal (5.08 ± 1.17, N = 66) and hyperkinetic (8.99 ± 1.31, N = 41) subgroups. In contrast, cardiac output rose appropriately with in 141 patients with chronic fatigue but without POTS, exhibiting a normal distribution and an average slope of 6.10 ± 2.09 L·min(-1) per L·min(-1). Mean arterial blood pressure and pulse pressure from rest to exercise rose similarly in both groups.

We conclude that 40% of POTS adolescents demonstrate a hyperkinetic circulation during exercise. We attribute this to failure of normal regional vasoconstriction during exercise, such that patients must increase flow through an inappropriately vasodilated systemic circulation to maintain perfusion pressure.

© 2014 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

 

Source: Pianosi PT, Goodloe AH, Soma D, Parker KO, Brands CK, Fischer PR. High flow variant postural orthostatic tachycardia syndrome amplifies the cardiac output response to exercise in adolescents. Physiol Rep. 2014 Aug 28;2(8). pii: e12122. doi: 10.14814/phy2.12122. Print 2014 Aug 1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4246579/ (Full article)

 

Altered immune pathway activity under exercise challenge in Gulf War Illness: an exploratory analysis

Abstract:

Though potentially linked to the basic physiology of stress response we still have no clear understanding of Gulf War Illness (GWI), a debilitating illness presenting with a complex constellation of immune, endocrine and neurological symptoms. Here we compared male GWI (n=20) with healthy veterans (n=22) and subjects with chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) (n=7). Blood was drawn during a Graded eXercise Test (GXT) prior to exercise, at peak effort (VO2 max) and 4-h post exercise. Affymetrix HG U133 plus 2.0 microarray gene expression profiling in peripheral blood mononuclear cells (PBMCs) was used to estimate activation of over 500 documented pathways. This was cast against ELISA-based measurement of 16 cytokines in plasma and flow cytometric assessment of lymphocyte populations and cytotoxicity. A 2-way ANOVA corrected for multiple comparisons (q statistic <0.05) indicated significant increases in neuroendocrine-immune signaling and inflammatory activity in GWI, with decreased apoptotic signaling. Conversely, cell cycle progression and immune signaling were broadly subdued in CFS. Partial correlation networks linking pathways with symptom severity via changes in immune cell abundance, function and signaling were constructed.

Central to these were changes in IL-10 and CD2+ cell abundance and their link to two pathway clusters. The first consisted of pathways supporting neuronal development and migration whereas the second was related to androgen-mediated activation of NF-κB. These exploratory results suggest an over-expression of known exercise response mechanisms as well as illness-specific changes that may involve an overlapping stress-potentiated neuro-inflammatory response.

Copyright © 2012 Elsevier Inc. All rights reserved.

 

Source: Broderick G, Ben-Hamo R, Vashishtha S, Efroni S, Nathanson L, Barnes Z, Fletcher MA, Klimas N. Altered immune pathway activity under exercise challenge in Gulf War Illness: an exploratory analysis. Brain Behav Immun. 2013 Feb;28:159-69. doi: 10.1016/j.bbi.2012.11.007. Epub 2012 Nov 29. https://www.ncbi.nlm.nih.gov/pubmed/23201588

 

Mitochondrial dysfunction and the pathophysiology of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS)

Abstract:

The objectives of this study are to test the hypothesis that the fatigue and accompanying symptoms of Chronic Myalgic Encephalomyelitis/Fatigue Syndrome are in part due to defects in energy provision at the cellular level, and to understand the pathophysiology of the defects so that effective medical intervention can be implemented.

We performed an audit of 138 patients (ages 18-65) diagnosed with ME/CFS and attending a private practice. The patients and 53 normal, healthy controls had the ATP Profile test carried out on neutrophils from a 3-ml venous blood sample. This test yields 6 numerical factors that describe the availability of ATP and the efficiency of oxidative phosphorylation in mitochondria. Other biomedical measurements, including the concentration of cell-free DNA in plasma, were made. The results of the audit are compared with the controls and a previous cohort of 61 patients. We find that all patients tested have measureable mitochondrial dysfunction which correlates with the severity of the illness.

The patients divide into two main groups differentiated by how cellular metabolism attempts to compensate for the dysfunction. Comparisons with exercise studies suggest that the dysfunction in neutrophils also occurs in other cells. This is confirmed by the cell-free DNA measurements which indicate levels of tissue damage up to 3.5 times the normal reference range. The major immediate causes of the dysfunction are lack of essential substrates and partial blocking of the translocator protein sites in mitochondria. The ATP Profile is a valuable diagnostic tool for the clinical management of ME/CFS.

 

Source: Booth NE, Myhill S, McLaren-Howard J. Mitochondrial dysfunction and the pathophysiology of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). Int J Clin Exp Med. 2012;5(3):208-20. Epub 2012 Jun 15. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3403556/ (Full article)

 

Effects of exercise on behavior and peripheral blood lymphocyte apoptosis in a rat model of chronic fatigue syndrome

Abstract:

This study examined the effects of exercise on behavior and peripheral blood leukocyte apoptosis in a rat model of chronic fatigue syndrome (CFS).

Thirty-six healthy male Sprague-Dawley rats were equally randomized into 3 groups: the control group, CFS model group and the exercise group in terms of body weight. A total of 25 rats entered the final statistical analysis due to 11 deaths during the study. CFS model was established by subjecting the rats in CFS model group and exercise group to electric shock, chronic restraint stress and cold water swim. Besides, rats in the exercise group took running wheel exercise.

After a week of conditioning feeding, model construction and running wheel exercise were performed simultaneously, and lasted for 23 consecutive days. The behavior experiments, including running wheel exercise, open-field test, tail suspension test and Morris water maze test, were conducted, either before or after the model establishment. Rats were sacrificed and peripheral blood was obtained for the assessment of lymphocyte apoptosis index by flow cytometry (FCM).

It was found that as compared with those in the control group, the weight of the rats was decreased obviously (P<0.01), the mobility time in the open-field and the tail suspension tests was shortened significantly (P<0.01), the time to locate the platform was enhanced (P<0.01) and the cell apoptosis index was increased substantially (P<0.01) in the CSF model group.

Meanwhile, in comparison to the model group, the behavior in the open-field and the tail suspension tests was improved significantly (P<0.05), and the apoptosis index decreased remarkably (P<0.01) in the exercise group. It is concluded that sport intervention can prevent lymphocyte apoptosis and improve animal behavior rather than the memory.

 

Source: Zou J, Yuan J, Lv S, Tu J. Effects of exercise on behavior and peripheral blood lymphocyte apoptosis in a rat model of chronic fatigue syndrome. J Huazhong Univ Sci Technolog Med Sci. 2010 Apr;30(2):258-64. doi: 10.1007/s11596-010-0225-y. Epub 2010 Apr 21. https://www.ncbi.nlm.nih.gov/pubmed/20407885

 

Prospective observational study of treatments for unexplained chronic fatigue

Abstract:

BACKGROUND: Unexplained chronic fatigue is a frequent complaint in primary care. A prospective observational study design was used to evaluate whether certain commonly used therapies for unexplained chronic fatigue may be effective.

METHOD: Subjects with unexplained chronic fatigue of unknown etiology for at least 6 months were recruited from the Wisconsin Chronic Fatigue Syndrome Association, primary care clinics, and community chronic fatigue syndrome presentations. The primary outcome measure was change in a 5-question fatigue score from 6 months to 2 years. Self-reported interventions tested included prescribed medications, non-prescribed supplements and herbs, lifestyle changes, alternative therapies, and psychological support. Linear regression analysis was used to test the association of each therapy with the outcome measure after adjusting for statistically significant prognostic factors.

RESULTS: 155 subjects provided information on fatigue and treatments at baseline and follow-up. Of these subjects, 87% were female and 79% were middle-aged. The median duration of fatigue was 6.7 years. The percentage of users who found a treatment helpful was greatest for coenzyme Q10 (69% of 13 subjects), dehydroepiandrosterone (DHEA) (65% of 17 subjects), and ginseng (56% of 18 subjects). Treatments at 6 months that predicted subsequent fatigue improvement were vitamins (p = .08), vigorous exercise (p = .09), and yoga (p = .002). Magnesium (p = .002) and support groups (p = .06) were strongly associated with fatigue worsening from 6 months to 2 years. Yoga appeared to be most effective for subjects who did not have unclear thinking associated with the fatigue.

CONCLUSION: Certain alternative therapies for unexplained chronic fatigue, especially yoga, deserve testing in randomized controlled trials.

 

Source: Bentler SE, Hartz AJ, Kuhn EM. Prospective observational study of treatments for unexplained chronic fatigue. J Clin Psychiatry. 2005 May;66(5):625-32. http://www.ncbi.nlm.nih.gov/pubmed/15889950

 

The role of tryptophan in fatigue in different conditions of stress

Abstract:

Tryptophan is the precursor for the neurotransmitter 5-hydroxytryptamine (5-HT), which is involved in fatigue and sleep. It is present in bound and free from in the blood, where the concentration is controlled by albumin binding to tryptophan. An increase in plasma free tryptophan leads to an increased rate of entry of tryptophan into the brain. This should lead to a higher level of 5-HT which may cause central fatigue. Central fatigue is implicated in clinical conditions such as chronic fatigue syndrome and post-operative fatigue. Increased plasma free tryptophan leads to an increase in the plasma concentration ratio of free tryptophan to the branched chain amino acids (BCAA) which compete with tryptophan for entry into the brain across the blood-brain barrier.

The plasma concentrations of these amino acids were measured in chronic fatigue syndrome patients (CFS) before and after exercise (Castell et al., 1998), and in patients undergoing major surgery (Yamamoto et al., 1997). In the CFS patients, the pre-exercise concentration of plasma free tryptophan was higher than in controls (p < 0.05) but did not change during or after exercise. This might indicate an abnormally high level of brain 5-HT in CFS patients leading to persistent fatigue.

In the control group, plasma free tryptophan was increased after maximal exercise (p < 0.001), returning towards baseline levels 60 min later. The apparent failure of the CFS patients to change the plasma free tryptophan concentration or the free tryptophan/BCAA ratio during exercise may indicate increased sensitivity of brain 5-HT receptors, as has been demonstrated in other studies (Cleare et al., 1995).

In post-operative recovery after major surgery plasma free tryptophan concentrations were markedly increased compared with baseline levels; the plasma free tryptophan/BCAA concentration ratio was also increased after surgery. Plasma albumin concentrations were decreased after surgery: this may account for the increase in plasma free tryptophan levels.

Provision of BCAA has improved mental performance in athletes after endurance exercise (Blomstrand et al., 1995, 1997). It is suggested that BCAA supplementation may help to counteract the effects of an increase in plasma free tryptophan, and may thus improve the status of patients during or after some clinically stressful conditions.

 

Source: Castell LM, Yamamoto T, Phoenix J, Newsholme EA. The role of tryptophan in fatigue in different conditions of stress. Adv Exp Med Biol. 1999;467:697-704. http://www.ncbi.nlm.nih.gov/pubmed/10721121

 

Acute phase responses and cytokine secretion in chronic fatigue syndrome

Abstract:

This study addresses the hypothesis that clinical manifestations of chronic fatigue syndrome (CFS) are due in part to abnormal production of or sensitivity to cytokines such as interleukin-1beta (IL-1beta) and IL-6 under basal conditions or in response to a particular physical stress: 15 min of exercise consisting of stepping up and down on a platform adjusted to the height of the patella. The study involved 10 CFS patients and 11 age-, sex-, and activity-matched controls: of these, 6 patients and 4 controls were tested in both the follicular and the luteal phases of the menstrual cycle, and the remainder were tested in only one phase, for a total of 31 experimental sessions.

Prior to exercise, plasma concentrations of the acute phase reactant alpha2-macroglobulin were 29% higher in CFS patients (P < 0.008) compared to controls. Secretion of IL-6 was generally higher for CFS patients (approximately 38%), however, this difference was statistically significant only if all values over a 3-day period were analyzed by repeated-measures ANOVA (P = 0.035). IL-6 secretion correlated with plasma alpha2-macroglobulin in control subjects at rest (R = 0.767, P = 0.001).

Immediately after exercise, the CFS patients reported greater ratings of perceived exertion (P=0.027) compared to the healthy control subjects. Ratings of perceived exertion correlated with IL-1beta secretion by cells from healthy control subjects (R = 0.603, P = 0.022), but not from CFS patients, and IL-1beta secretion was not different between groups. Exercise induced a slight (< 12%) but significant (P = 0.006) increase in IL-6 secretion, but the responses of the CFS patients were not different than controls. Furthermore, no significant exercise-induced changes in body temperature or plasma alpha2-macroglobulin were observed.

These data indicate that under basal conditions, CFS is associated with increased IL-6 secretion which is manifested by chronically elevated plasma alpha2-macroglobulin concentrations. These modest differences suggest that cytokine dysregulation is not a singular or dominant factor in the pathogenesis of CFS.

 

Source: Cannon JG, Angel JB, Ball RW, Abad LW, Fagioli L, Komaroff AL. Acute phase responses and cytokine secretion in chronic fatigue syndrome. J Clin Immunol. 1999 Nov;19(6):414-21. http://www.ncbi.nlm.nih.gov/pubmed/10634215