Low-grade inflammation and arterial wave reflection in patients with chronic fatigue syndrome

Abstract:

Some of the symptoms reported by people with CFS (chronic fatigue syndrome) are associated with various cardiovascular phenomena. Markers of cardiovascular risk, including inflammation and oxidative stress, have been demonstrated in some patients with CFS, but little is known about the relationship between these and prognostic indicators of cardiovascular risk in this patient group. In the present study, we investigated the relationship between inflammation and oxidative stress and augmentation index, a measure of arterial stiffness, in 41 well-characterized patients with CFS and in 30 healthy subjects.

AIx@75 (augmentation index normalized for a heart rate of 75 beats/min) was significantly greater in patients with CFS than in control subjects (22.5+/-1.7 compared with 13.3+/-2.3% respectively; P=0.002). Patients with CFS also had significantly increased levels of CRP (C-reactive protein) (2.58+/-2.91 compared with 1.07+/-2.16 mug/ml respectively; P<0.01) and 8-iso-prostaglandin F(2alpha) isoprostanes (470.7+/-250.9 compared with 331.1+/-97.6 pg/ml respectively; P<0.005). In patients with CFS, AIx@75 correlated significantly with logCRP (r=0.507, P=0.001), isoprostanes (r=0.366, P=0.026), oxidized LDL (low-density lipoprotein) (r=0.333, P=0.039) and systolic blood pressure (r=0.371, P=0.017). In a stepwise multiple regression model, including systolic and diastolic blood pressure, body mass index, CRP, tumour necrosis factor-alpha, interleukin-1, oxidized LDL, high-density lipoprotein-cholesterol levels, isoprostanes, age and gender, AIx@75 was independently associated with logCRP (beta=0.385, P=0.006), age (beta=0.363, P=0.022) and female gender (beta=0.302, P=0.03) in patients with CFS.

The combination of increased a, inflammation and oxidative stress may result in an increased risk of future cardiovascular events. Assessment of arterial wave reflection might be useful for determining cardiovascular risk in this patient group.

 

Source: Spence VA, Kennedy G, Belch JJ, Hill A, Khan F. Low-grade inflammation and arterial wave reflection in patients with chronic fatigue syndrome. Clin Sci (Lond). 2008 Apr;114(8):561-6. https://www.ncbi.nlm.nih.gov/pubmed/18031285

 

Valacyclovir treatment in Epstein-Barr virus subset chronic fatigue syndrome: thirty-six months follow-up

Abstract:

BACKGROUND: We hypothesized that subset classification of Epstein-Barr virus (EBV) in chronic fatigue syndrome (CFS) is required. At first, a blinded-random placebo-controlled trial of valacyclovir in EBV CFS subset was performed (Group 1), and this EBV subset was followed for thirty-six months (Group 2). Patients were given valacyclovir at 14.3 mg/kg every 6 hours. The validated Energy Index (EI) point score assessing physical functional capacity, Holter monitor, multigated (radionuclide) MUGA rest/stress ventriculographic examination, EBV serum IgM viral capsid antibodies (VCA), and EBV early antigen diffuse (EA) were followed.

After six-months, Group 1 CFS patients receiving valacyclovir experienced an increased mean least square EI point score +1.12 units (122 kcal/day), while the placebo cohort increased +0.42 EI units (65 kcal/day). EI point scores at Group 2 increased progressively. Sinus tachycardias decreased and abnormal cardiac wall motion improved. Serum antibody titers to EBV VCA IgM decreased. Patients resumed normal activities.

 

Source: Lerner AM, Beqaj SH, Deeter RG, Fitzgerald JT. Valacyclovir treatment in Epstein-Barr virus subset chronic fatigue syndrome: thirty-six months follow-up. In Vivo. 2007 Sep-Oct;21(5):707-13. http://iv.iiarjournals.org/content/21/5/707.long (Full article)

 

A clinical trial of acupuncture for treating chronic fatigue syndrome in Hong Kong

Abstract:

OBJECTIVE: To evaluate the efficacy of acupuncture in treating chronic fatigue syndrome (CFS) in Hong Kong.

METHODS: A single-blinded, randomized controlled trial design was adopted. Participants meeting inclusion criteria were randomly assigned to a treatment and a control group according to 1:1 ratio, resulting in an effective sample size of 99, with 50 and 49 patients in treatment and control group respectively. The same set of acupuncture points, which were selected according to traditional Chinese medicine theories, was applied in both groups, while conventional needle acupuncture was applied in treatment group and sham acupuncture (without skin penetration) was applied in control group. Schedule of treatment was the same in both groups, i.e. twice a week for 4 weeks. Key outcome measures were Chalder’s Fatigue Scale, diagnostic criteria for CFS of the US’s Centre for Disease Control and SF-12 health-related quality of life (HQOL) questionnaire. Adverse events, if any, were recorded.

RESULTS: Improvements in physical and mental fatigue and HQOL in both groups were observed, but the improvements in treatment group were significantly bigger than in control group (P<0.01 or P<0.05). No adverse events occurred.

CONCLUSION: Acupuncture is a safe, effective treatment for CFS.

 

Source: Yiu YM, Ng SM, Tsui YL, Chan YL. A clinical trial of acupuncture for treating chronic fatigue syndrome in Hong Kong. Zhong Xi Yi Jie He Xue Bao. 2007 Nov;5(6):630-3. [Article in Chinese] http://www.jcimjournal.com/jim/showAbstrPage.aspx?articleid=167219772007060630 (Full article)

 

The relationship between prior psychiatric disorder and chronic fatigue: evidence from a national birth cohort study

Abstract:

BACKGROUND: Increased rates of psychiatric disorder have previously been reported in those diagnosed with chronic fatigue syndrome (CFS) or myalgic encephalomyelitis (ME), although the direction of causation in this relationship has not been established. We aimed to test the hypothesis that individuals with self-reported CFS/ME have increased levels of psychiatric disorder prior to the onset of their fatigue symptoms.

METHOD: A total of 5,362 participants were prospectively followed with various measures of personality, psychiatric disorder and fatigue levels collected over the first 43 years of their life. CFS/ME was identified through self-report during a semi-structured interview at age 53 years.

RESULTS: Thirty-four (1.1%) of the 3,035 subjects assessed at age 53 years reported a diagnosis of CFS/ME. CFS/ME was more common among females, but there was no association between CFS/ME and either social class, social mobility or educational level. Those with psychiatric illness between the ages of 15 and 36 years were more likely to report CFS/ME later in life with an odds ratio (OR, adjusted for sex) of 2.65 [95% confidence interval (CI) 1.26-5.57, p=0.01]. Increased levels of psychiatric illness, in particular depression and anxiety, were present prior to the occurrence of fatigue symptoms. There was a dose-response relationship between the severity of psychiatric symptoms and the likelihood of later CFS/ME. Personality factors were not associated with a self-reported diagnosis of CFS/ME.

CONCLUSIONS: This temporal, dose-response relationship suggests that psychiatric disorders, or shared risk factors for psychiatric disorders, are likely to have an aetiological role in some cases of CFS/ME.

 

Source: Harvey SB, Wadsworth M, Wessely S, Hotopf M. The relationship between prior psychiatric disorder and chronic fatigue: evidence from a national birth cohort study. Psychol Med. 2008 Jul;38(7):933-40. Epub 2007 Nov 2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3196526/ (Full article)

 

Possible use of repeated cold stress for reducing fatigue in chronic fatigue syndrome: a hypothesis

Abstract:

BACKGROUND: Physiological fatigue can be defined as a reduction in the force output and/or energy-generating capacity of skeletal muscle after exertion, which may manifest itself as an inability to continue exercise or usual activities at the same intensity. A typical example of a fatigue-related disorder is chronic fatigue syndrome (CFS), a disabling condition of unknown etiology and with uncertain therapeutic options. Recent advances in elucidating pathophysiology of this disorder revealed hypofunction of the hypothalamic-pituitary-adrenal axis and that fatigue in CFS patients appears to be associated with reduced motor neurotransmission in the central nervous system (CNS) and to a smaller extent with increased fatigability of skeletal muscle. There is also some limited evidence that CFS patients may have excessive serotonergic activity in the brain and low opioid tone.

PRESENTATION OF THE HYPOTHESIS: This work hypothesizes that repeated cold stress may reduce fatigue in CFS because brief exposure to cold may transiently reverse some physiological changes associated with this illness. For example, exposure to cold can activate components of the reticular activating system such as raphe nuclei and locus ceruleus, which can result in activation of behavior and increased capacity of the CNS to recruit motoneurons. Cold stress has also been shown to reduce the level of serotonin in most regions of the brain (except brainstem), which would be consistent with reduced fatigue according to animal models of exercise-related fatigue. Finally, exposure to cold increases metabolic rate and transiently activates the hypothalamic-pituitary-adrenal axis as evidenced by a temporary increase in the plasma levels of adrenocorticotropic hormone, beta-endorphin and a modest increase in cortisol. The increased opioid tone and high metabolic rate could diminish fatigue by reducing muscle pain and accelerating recovery of fatigued muscle, respectively.

TESTING THE HYPOTHESIS: To test the hypothesis, a treatment is proposed that consists of adapted cold showers (20 degrees Celsius, 3 minutes, preceded by a 5-minute gradual adaptation to make the procedure more comfortable) used twice daily.

IMPLICATIONS OF THE HYPOTHESIS: If testing supports the proposed hypothesis, this could advance our understanding of the mechanisms of fatigue in CFS.

 

Source: Shevchuk NA. Possible use of repeated cold stress for reducing fatigue in chronic fatigue syndrome: a hypothesis. Behav Brain Funct. 2007 Oct 24;3:55. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2164952/ (Full article)

 

The thoughts and methods for clinical research on acupuncture treatment of chronic fatigue syndrome

Abstract:

The general situation of chronic fatigue syndrome (CFS) and the criteria for its diagnosis are discussed, and it is put forward that making qi and blood of the zang-fu organs balanced is the key to acupuncture treatment of the disease. Such aspects as case selection, point selection and therapeutic assessment are also discussed in the present paper.

 

Source: Yao R. The thoughts and methods for clinical research on acupuncture treatment of chronic fatigue syndrome. J Tradit Chin Med. 2007 Sep;27(3):163-5 http://www.journaltcm.com/modules/Journal/contents/stories/073/1.pdf (Full article)

 

IFN-gamma mediated pathways in patients with fatigue and chronic active Epstein Barr virus-infection

Abstract:

BACKGROUND: Chronic active Epstein Barr virus (EBV)-infection is characterized by mononucleosis like symptoms including fatigue, lymphadenopathy and/or hepatosplenomegaly and serologic evidence for ongoing EBV replication. Interferon-gamma (IFN-gamma) triggers several antiviral mechanisms in target cells including the induction of indoleamine-2,3-dioxygenase (IDO), which degrades the essential amino acid tryptophan to kynurenine. Because tryptophan is a precursor of the neurotransmitter 5-hydroxytryptamine (serotonin), tryptophan depletion by IDO can cause mood disturbances in patients with chronic immune activation.

METHODS: This study investigated the tryptophan metabolism in 20 patients with chronic active EBV-infection, who were followed up for 4 to 8 months and in 10 healthy age-matched controls. The clinical suspicion of chronic active EBV infection was verified by the presence of circulating antibodies against EBV early antigen (EA) and virus capsid antigen (VCA).

RESULTS: Patients with detectable EBV-DNA had higher serum neopterin (p<0.01) and lower tryptophan concentrations (p=0.01) than EBV-DNA negative patients. Serum concentrations of neopterin, indicating Th-1 mediated immune activation via IFN-gamma, were positively correlated to enhanced tryptophan degradation (rs=0.650, p<0.001) in patients, but not in healthy individuals. Patients suffering from more severe symptoms (as assessed by questionnaires) tended to have aggravated tryptophan degradation.

CONCLUSION: Our data show that EBV viremia is associated with cell-mediated immune activation and increased tryptophan degradation, which may partly account for the symptoms found in this disorder.

 

Source: Bellmann-Weiler R, Schroecksnadel K, Holzer C, Larcher C, Fuchs D, Weiss G. IFN-gamma mediated pathways in patients with fatigue and chronic active Epstein Barr virus-infection. J Affect Disord. 2008 May;108(1-2):171-6. Epub 2007 Oct 22. https://www.ncbi.nlm.nih.gov/pubmed/17945348

 

Alexithymia in adolescents with chronic fatigue syndrome

Abstract:

BACKGROUND: Alexithymia is postulated as an important factor in the development of medically unexplained physical symptoms. Chronic fatigue syndrome (CFS) is presently medically unexplained. The aim of this study was to investigate whether the prevalence of alexithymia was higher in adolescents with CFS compared to healthy adolescents. Comorbidity such as anxiety and depression were analyzed as possible confounding factors. Secondly, alexithymia was investigated as a prognostic factor for the recovery of CFS.

METHODS: A cross-sectional study was performed among 40 adolescent outpatients diagnosed with CFS and 36 healthy controls. The 20-item Toronto Alexithymia Scale was used to assess all participants for alexithymia. Additionally, all participants completed a number of questionnaires regarding fatigue (Checklist Individual Strength), somatic complaints (Checklist Somatization Inventory), depression (Children’s Depression Inventory), and trait anxiety (Spielberger State Trait Anxiety Questionnaire). A follow-up study was performed among the CFS adolescents 1 1/2 years after the initial assessment.

RESULTS: CFS adolescents scored higher only on the subscale identifying feelings of the TAS-20 [mean difference after adjustment for depression and anxiety 2.8 (95% CI: 0.6; 4.9]. Twelve CFS adolescents (30%) fulfilled criteria for alexithymia. This subgroup was characterized by higher scores for depression and anxiety and equal scores for fatigue and somatic complaints. At follow-up, no differences in recovery were established between the alexithymic and nonalexithymic CFS adolescents.

CONCLUSIONS: Alexithymia neither appears to be a unique correlate of CFS nor to be a prognostic factor for recovery of the CFS illness.

 

Source: van de Putte EM, Engelbert RH, Kuis W, Kimpen JL, Uiterwaal CS. Alexithymia in adolescents with chronic fatigue syndrome. J Psychosom Res. 2007 Oct;63(4):377-80. https://www.ncbi.nlm.nih.gov/pubmed/17905045

 

Twin analyses of fatigue

Abstract:

Prolonged fatigue equal to or greater than 1 month duration and chronic fatigue equal to or greater than 6 months duration are both commonly seen in clinical practice, yet little is known about the etiology or epidemiology of either symptom. Chronic fatigue syndrome (CFS), while rarer, presents similar challenges in determining cause and epidemiology. Twin studies can be useful in elucidating genetic and environmental influences on fatigue and CFS. The goal of this article was to use biometrical structural equation twin modeling to examine genetic and environmental influences on fatigue, and to investigate whether these influences varied by gender. A total of 1042 monozygotic (MZ) twin pairs and 828 dizygotic (DZ) twin pairs who had completed the University of Washington Twin Registry survey were assessed for three fatigue-related variables: prolonged fatigue, chronic fatigue, and CFS. Structural equation twin modeling was used to determine the relative contributions of additive genetic effects, shared environmental effects, and individual-specific environmental effects to the 3 fatigue conditions. In women, tetrachoric correlations were similar for MZ and DZ pairs for prolonged and chronic fatigue, but not for CFS. In men, however, the correlations for prolonged and chronic fatigue were higher in MZ pairs than in DZ pairs. About half the variance for both prolonged and chronic fatigue in males was due to genetic effects, and half due to individual-specific environmental effects. For females, most variance was due to individual environmental effects.

 

Source: Schur E, Afari N, Goldberg J, Buchwald D, Sullivan PF. Twin analyses of fatigue. Twin Res Hum Genet. 2007 Oct;10(5):729-33. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2953372/ (Full article)

 

Chronic fatigue syndrome and related disorders in UK veterans of the Gulf War 1990-1991: results from a two-phase cohort study

Abstract:

BACKGROUND: The aim was to determine the prevalence of chronic fatigue syndrome (CFS), chronic fatigue and fibromyalgia in UK military personnel after the Gulf War 1990-1991.

METHOD: A two-phase cohort study was used. Three randomly selected subsamples identified from a population-based cross-sectional postal survey of over 10,000 current and ex-service UK military personnel (Gulf veterans were those deployed to the Gulf War 1990-1991; non-Gulf veterans were Bosnia peacekeepers 1992-1997 and those on active duty during the Gulf War 1990-1991 but not deployed) were recruited. Their disability status was assessed using the Short Form 36 physical functioning scale; Gulf veterans who reported physical disability (n=111) were compared with non-Gulf (n=133) veterans who reported similar levels of physical disability. Screening for known medical and psychiatric conditions was conducted to exclude medical explanations for disability and symptomatic distress. Standardised criteria for CFS, chronic fatigue and fibromyalgia were used.

RESULTS: Disabled Gulf veterans were more likely to be overweight, have elevated gamma-glutamyl transferase levels and screen positive for hypertension. There were no other clinically significant differences in clinical markers for medically explainable conditions. Disabled Gulf veterans were more likely than similarly disabled Bosnia and Era veterans (adjusted odds ratio 7.8, 95% confidence interval 2.5-24.5) to meet the criteria for CFS. Rates for other medically unexplained conditions were not significantly increased.

CONCLUSIONS: Symptoms in keeping with CFS account for a significant part of the symptomatic distress in Gulf veterans.

Comment in: Chronic fatigue in Gulf War veterans: should it be treated as chronic fatigue syndrome? [Psychol Med. 2009]

 

Source: Ismail K, Kent K, Sherwood R, Hull L, Seed P, David AS, Wessely S. Chronic fatigue syndrome and related disorders in UK veterans of the Gulf War 1990-1991: results from a two-phase cohort study. Psychol Med. 2008 Jul;38(7):953-61. Epub 2007 Sep 25. https://www.ncbi.nlm.nih.gov/pubmed/17892626