Cognitive deficits in patients with chronic fatigue syndrome compared to those with major depressive disorder and healthy controls

Abstract:

OBJECT: Chronic fatigue syndrome (CFS) patients report usually cognitive complaints. They also have frequently comorbid depression that can be considered a possible explanation for their cognitive dysfunction. We evaluated the cognitive performance of patients with CFS in comparison with a control group of healthy volunteers and a group of patients with MDD.

PATIENTS AND METHODS: Twenty-five patients with CFS, 25 patients with major depressive disorder (MDD), and 25 healthy control subjects were given standardized tests of attention, working memory, and verbal and visual episodic memory, and were also tested for effects related to lack of effort/simulation, suggestibility, and fatigue.

RESULTS: Patients with CFS had slower phasic alertness, and also had impaired working, visual and verbal episodic memory compared to controls. They were, however, no more sensitive than the other groups to suggestibility or to fatigue induced during the cognitive session. Cognitive impairments in MDD patients were strongly associated with depression and subjective fatigue; in patients with CFS, there was a weaker correlation between cognition and depression (and no correlation with fatigue).

CONCLUSIONS: This study confirms the presence of an objective impairment in attention and memory in patients with CFS but with good mobilization of effort and without exaggerated suggestibility.

Copyright © 2011 Elsevier B.V. All rights reserved.

 

Source: Constant EL, Adam S, Gillain B, Lambert M, Masquelier E, Seron X. Cognitive deficits in patients with chronic fatigue syndrome compared to those with major depressive disorder and healthy controls. Clin Neurol Neurosurg. 2011 May;113(4):295-302. doi: 10.1016/j.clineuro.2010.12.002. Epub 2011 Jan 20. https://www.ncbi.nlm.nih.gov/pubmed/21255911

 

The role of changes in activity as a function of perceived available and expended energy in nonpharmacological treatment outcomes for ME/CFS

Abstract:

Nonpharmacological interventions for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) often emphasize gradual increases in activity to promote improvement in physical functioning and fatigue. The energy envelope theory may provide a framework for understanding the relationship between changes in activity level and outcomes for patients with ME/CFS. This study examined the relationship between energy envelope and changes in activity after nonpharmacological interventions in a sample of 44 adults with ME/CFS.

Results showed that those who were within their energy envelope before treatment showed more improvement in physical functioning and fatigue compared with those outside of their energy envelope. These findings suggest that an assessment of perceived available and expended energy could help guide the development of individualized nonpharmacological interventions for people with ME/CFS.

© 2010 Wiley Periodicals, Inc.

 

Source: Brown M, Khorana N, Jason LA. The role of changes in activity as a function of perceived available and expended energy in nonpharmacological treatment outcomes for ME/CFS. J Clin Psychol. 2011 Mar;67(3):253-60. doi: 10.1002/jclp.20744. Epub 2010 Oct 25. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3164291/ (Full article)

 

The economic impact of chronic fatigue syndrome in Georgia: direct and indirect costs

Abstract:

BACKGROUND: Chronic fatigue syndrome (CFS) is a debilitating chronic illness affecting at least 4 million people in the United States. Understanding its cost improves decisions regarding resource allocation that may be directed towards treatment and cure, and guides the evaluation of clinical and community interventions designed to reduce the burden of disease.

METHODS: This research estimated direct and indirect costs of CFS and the impact on educational attainment using a population-based, case-control study between September 2004 and July 2005, Georgia, USA. Participants completed a clinical evaluation to confirm CFS, identify other illnesses, and report on socioeconomic factors. We estimated the effect of CFS on direct medical costs (inpatient hospitalizations, provider visits, prescription medication spending, other medical supplies and services) and loss in productivity (employment and earnings) with a stratified sample (n = 500) from metropolitan, urban, and rural Georgia. We adjusted medical costs and earnings for confounders (age, sex, race/ethnicity, education, and geographic strata) using econometric models and weighted estimates to reflect response-rate adjusted sampling rates.

RESULTS: Individuals with CFS had mean annual direct medical costs of $5,683. After adjusting for confounding factors, CFS accounted for $3,286 of these costs (p < 0.01), which were driven by increased provider visits and prescription medication use. Nearly one-quarter of these expenses were paid directly out-of pocket by those with CFS. Individuals with CFS reported mean annual household income of $23,076. After adjustment, CFS accounted for $8,554 annually in lost household earnings (p < 0.01). Lower educational attainment accounted for 19% of the reduction in earnings associated with CFS.

CONCLUSIONS: Study results indicate that chronic fatigue syndrome may lead to substantial increases in healthcare costs and decreases in individual earnings. Studies have estimated up to 2.5% of non-elderly adults may suffer from CFS. In Georgia, a state with roughly 5.5 million people age 18-59, illness could account for $452 million in total healthcare expenditures and $1.2 billion of lost productivity.

 

Source: Lin JM, Resch SC, Brimmer DJ, Johnson A, Kennedy S, Burstein N, Simon CJ. The economic impact of chronic fatigue syndrome in Georgia: direct and indirect costs. Cost Eff Resour Alloc. 2011 Jan 21;9(1):1. doi: 10.1186/1478-7547-9-1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3033815/ (Full article)

 

Heterologous immunity: immunopathology, autoimmunity and protection during viral infections

There is a strong association between infection-related cell-mediated immunity and autoimmune diseases such as diabetes, multiple sclerosis (MS), rheumatoid arthritis (RA) and lupus erythematosis (SLE)1. Infections have also been associated with unusual immunopathologies of unknown origin, such as Wegner granulomatosis, sarcoidosis, colitis, panniculitis, bronchiolitis obliterans and even chronic fatigue syndrome. Despite exhaustive efforts, a definitive link between one particular pathogen and any of one these pathologies has never been found. More often several pathogens have become associated with each of these conditions. For instance multiple sclerosis has been associated with Epstein Barr virus (EBV), measles virus, HHV-6, varicella-zoster virus, and Picornaviruses2-6. Panniculitis in the form of erythema nodosum and bronchiolitis obliterans have both been associated with unusual cell-mediated immune responses that occur following non-specified viral or intracellular bacterial infections 7-9. Erythema nodosum, which has also been associated with Crohn’s disease8, is a very painful condition, where nodules of inflamed subcutaneous fat often on the shins and forearms persist for months. There is no known therapy. Bronchiolitis obliterans is a lethal condition in humans where the bronchioles become occluded with immune cells and fibrinous material, with no known cause or treatment9.

Chronic fatigue syndrome (CFS) is another unusual multisystem disease which is thought to be associated with immune dysregulation. Over the past two decades millions of patients world wide have suffered from a clinical syndrome of disabling fatigue, myalgias, palpitations and cognitive dysfunction that lasts longer than 6 months. In 50% of cases it develops after a mild viral illness. Cases may appear sporadically or in clusters10,11. Many attempts have been made to define the syndrome on the basis of an etiologic agent. These agents have included Epstein-Barr virus10, Brucella12, Candida albicans13, Borrelia burgdorferi, and human herpesvirus-614,15. More recently it has been associated with enteroviruses and xenoretroviruses 16-18. The general conclusion has been that it is unlikely that the syndrome is caused by a single etiologic agent. The mechanisms mediating CFS are poorly understood, and there are few well designed studies examining its cause. The symptoms of CFS are similar to those experienced during viral infections such as infectious mononucleosis or influenza or in the setting of therapy with cytokines such as interferon or interleukin-2. It has been speculated that some or all the symptoms are reflective of an altered immune response to some pathogen with over production of one or more cytokines. An alternative hypothesis suggests that a number of infectious agents are involved and result in a regulatory imbalance of cytokines and the patient with CFS is unable to reestablish the appropriate balance of cytokines. These theories have been supported by reports of immune deficiency seen associated with CFS19.

 

Source: Selin LK, Wlodarczyk MF, Kraft AR, Nie S, Kenney LL, Puzone R, Celada F. Heterologous immunity: immunopathology, autoimmunity and protection during viral infections. Autoimmunity. 2011 Jun;44(4):328-47. doi: 10.3109/08916934.2011.523277. Epub 2011 Jan 20. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3633594/ (Full article)

 

Effect of Tuina on oxygen free radicals metabolism in patients with chronic fatigue syndrome

Abstract:

OBJECTIVE: To explore the mechanism of Tuina for treatment of chronic fatigue syndrome.

METHODS: A total of 90 patients were randomly divided into a Tuina group, a Taijiquan (take exercise) group and a Fluoxetine group, 30 cases in each group. They were treated with Tuina, Taijiquan and Fluoxetine, respectively. After a month, the therapeutic effects and the changes of malondialdehyde (MDA) content and the activity of serum superoxide dismutases (SOD) and serum glutathione peroxidase (GSH-Px) were observed.

RESULTS: The total effective rate of 93.3% (28/30) in the Tuina group was better than 80.0% (24/30) in the Taijiquan group and 73.3% (22/30) in the Fluoxetine group (both P < 0.05). After treatment, MDA contents in the three groups were all decreased (P < 0.01, P < 0.05), and the activity of SOD. GSH-Px in both the Tuina group and the Fluoxetine group were increased (P < 0.01, P < 0.05), and especially in the Tuina group with a significant difference as compared with the other two groups (P < 0.05, P < 0.01).

CONCLUSION: The therapeutic effect of the Tuina group is superior to that of the Taijiquan group and the Fluoxetine group. Tuina can regulate oxygen free radicals metabolism and clean superfluous oxygen free radicals to alleviate fatigue, which may be one of the mechanisms of Tuina in treating chronic fatigue syndrome.

 

Source: Liu CZ, Lei B. Effect of Tuina on oxygen free radicals metabolism in patients with chronic fatigue syndrome. Zhongguo Zhen Jiu. 2010 Nov;30(11):946-8. [Article in Chinese] https://www.ncbi.nlm.nih.gov/pubmed/21246855

 

Chronic fatigue syndrome/myalgic encephalomyelitis: an update

Abstract:

Chronic Fatigue Syndrome (CFS), also referred to as Myalgic Encephalomyelitis (ME), is a disease of unknown origin. It is classified as Post Viral Fatigue Syndrome (PVFS) in the WHO International Classification of Diseases (ICD) and listed as sub-category at G93.3 under chapter G93, other disorders of the brain. ME/CFS is primarily an endemic disorder but occurs in both epidemic and sporadic forms. It affects all racial-ethnic groups and is seen in all socioeconomic strata. A diagnosis of CFS is a diagnosis of exclusion, meaning other medical conditions, including psychiatric disorders, must be first ruled out. CFS is diagnosed if there is no other explanation for the fatigue and if the other symptoms did not develop before the fatigue. The estimated worldwide prevalence of CFS is 0.4?1 percent. The disease predominantly affects young adults, with a peak age of onset of between 20 and 40 years, and women, with a female to male ratio of 6:1. Mean illness duration ranges from 3 to 9 years.

The patho-physiological mechanism of CFS is unclear but the immunological pattern of CFS patients gleaned from various studies indicates that the immune system is chronically activated. Besides the role of environmental insults (xenobiotics, infectious agents, stress) the genetic features of patients are studied to evaluate their role in triggering the pathology. At present there are no specific pharmacological therapies to treat the disease but a variety of therapeutic approaches have been described as benefiting patients. Treatment programs are directed at relief of symptoms, with the goal of the patient regaining some level of preexisting function and well-being.

 

Source: Capelli E, Zola R, Lorusso L, Venturini L, Sardi F, Ricevuti G. Chronic fatigue syndrome/myalgic encephalomyelitis: an update. Int J Immunopathol Pharmacol. 2010 Oct-Dec;23(4):981-9. https://www.ncbi.nlm.nih.gov/pubmed/21244747

 

Health-related quality of life in patients with chronic fatigue syndrome: group cognitive behavioural therapy and graded exercise versus usual treatment. A randomised controlled trial with 1 year of follow-up

Abstract:

Chronic fatigue syndrome (CFS) produces physical and neurocognitive disability that significantly affects health-related quality of life (HRQL). Multidisciplinary treatment combining graded exercise therapy (GET) cognitive behavioural therapy (CBT) and pharmacological treatment has shown only short-term improvements.

Aim: To compare the effects on HRQL of (1) multidisciplinary treatment combining CBT, GET, and pharmacological treatment, and (2) usual treatment (exercise counselling and pharmacological treatment) at 12 months of follow-up.

Design: Prospective, randomized controlled trial with a follow-up of 12 months after the end of treatment.

Method: Patients consecutively diagnosed with CFS (Fukuda criteria) were randomly assigned to intervention (n = 60) or usual treatment (n = 60) groups. HRQL was assessed at baseline and 12 months by the Medical Outcomes Study Short-Form questionnaire (SF-36). Secondary outcomes included functional capacity for activities of daily living measured by the Stanford Health Assessment Questionnaire (HAQ) and comorbidities.

Results: At baseline, the two groups were similar, except for lower SF-36 emotional role scores in the intervention group. At 12 months, the intervention did not improve HRQL scores, with worse SF-36 physical function and bodily pain scores in the intervention group.

Conclusion: Multidisciplinary treatment was not superior to usual treatment at 12 months in terms of HRQL. The possible benefits of GET as part of multidisciplinary treatment for CFS should be assessed on an individual patient basis.

 

Source: Núñez M, Fernández-Solà J, Nuñez E, Fernández-Huerta JM, Godás-Sieso T, Gomez-Gil E. Health-related quality of life in patients with chronic fatigue syndrome: group cognitive behavioural therapy and graded exercise versus usual treatment. A randomised controlled trial with 1 year of follow-up. Clin Rheumatol. 2011 Mar;30(3):381-9. doi: 10.1007/s10067-010-1677-y. Epub 2011 Jan 15. https://www.ncbi.nlm.nih.gov/pubmed/21234629

For a list of references see: http://link.springer.com/article/10.1007/s10067-010-1677-y

 

CFS prevalence and risk factors over time

Abstract:

The present natural history study examined the course of CFS from 1995-97 (Wave 1) to approximately 10 years later (Wave 2) from a random, community-based, multi-ethnic population. The rate of CFS remained approximately the same over the period of time from Wave 1 to Wave 2, although a high level of mortality was found (18% of those with medical or psychiatric exclusions group, 12.5% for the CFS group). Physical measures of disability and fatigue, along with measures of specific somatic symptoms, better differentiate individuals who later are diagnosed with CFS than more psychosocial measures such as stress and coping.

 

Source: Jason LA, Porter N, Hunnell J, Rademaker A, Richman JA. CFS prevalence and risk factors over time. J Health Psychol. 2011 Apr;16(3):445-56. doi: 10.1177/1359105310383603. Epub 2011 Jan 11. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3166209/ (Full article)

 

Diagnostic accuracy of symptoms characterising chronic fatigue syndrome

Abstract:

PURPOSE: To determine the diagnostic accuracy for single symptoms and clusters of symptoms to distinguish between individuals with and without chronic fatigue syndrome (CFS).

METHODS: A cohort study was conducted in an exercise physiology laboratory in an academic setting. Thirty subjects participated in this study (n = 16 individuals with CFS; n = 14 non-disabled sedentary matched control subjects). An open-ended symptom questionnaire was administered 1 week following the second of two maximal cardiopulmonary exercise tests administered 24 h apart.

RESULTS: Receiver operating characteristics (ROC) curve analysis was significant for failure to recover within 1 day (area under the curve  =  0.864, 95% confidence interval [CI]: 0.706-1.00, p = 0.001) but not within 7 days. Clinimetric properties of failure to recover within 1 day to predict membership in the CFS cohort were sensitivity 0.80, specificity 0.93, positive predictive value 0.92, negative predictive value 0.81, positive likelihood ratio 11.4, and negative likelihood ratio 0.22. Fatigue demonstrated high sensitivity and modest specificity to distinguish between cohorts, while neuroendocrine dysfunction, immune dysfunction, pain, and sleep disturbance demonstrated high specificity and modest sensitivity. ROC analysis suggested cut-point of three associated symptoms (0.871, 95% CI: 0.717-1.00, p < 0.001). A significant binary logistic regression model (p < 0.001) revealed immune abnormalities, sleep disturbance and pain accurately classified 92% of individuals with CFS and 88% of control subjects.

CONCLUSIONS: A cluster of associated symptoms distinguishes between individuals with and without CFS. Fewer associated symptoms may be necessary to establish a diagnosis of CFS than currently described.

 

Source: Davenport TE, Stevens SR, Baroni K, Van Ness M, Snell CR. Diagnostic accuracy of symptoms characterising chronic fatigue syndrome. Disabil Rehabil. 2011;33(19-20):1768-75. doi: 10.3109/09638288.2010.546936. Epub 2011 Jan 6. https://www.ncbi.nlm.nih.gov/pubmed/21208154

 

Long-chain acylcarnitine deficiency in patients with chronic fatigue syndrome. Potential involvement of altered carnitine palmitoyltransferase-I activity

Abstract:

OBJECTIVE: The underlying aetiology of chronic fatigue syndrome is currently unknown; however, in the light of carnitine’s critical role in mitochondrial energy production, it has been suggested that chronic fatigue syndrome may be associated with altered carnitine homeostasis. This study was conducted to comparatively examine full endogenous carnitine profiles in patients with chronic fatigue syndrome and healthy controls.

DESIGN: A cross-sectional, observational study.

SETTING AND SUBJECTS: Forty-four patients with chronic fatigue syndrome and 49 age- and gender-matched healthy controls were recruited from the community and studied at the School of Pharmacy & Medical Sciences, University of South Australia.

MAIN OUTCOME MEASURES: All participants completed a fatigue severity scale questionnaire and had a single fasting blood sample collected which was analysed for l-carnitine and 35 individual acylcarnitine concentrations in plasma by LC-MS/MS.

RESULTS: Patients with chronic fatigue syndrome exhibited significantly altered concentrations of C8:1, C12DC, C14, C16:1, C18, C18:1, C18:2 and C18:1-OH acylcarnitines; of particular note, oleyl-L-carnitine (C18:1) and linoleyl-L-carnitine (C18:2) were, on average, 30-40% lower in patients than controls (P < 0.0001). Significant correlations between acylcarnitine concentrations and clinical symptomology were also demonstrated.

CONCLUSIONS: It is proposed that this disturbance in carnitine homeostasis is reflective of a reduction in carnitine palmitoyltransferase-I (CPT-I) activity, possibly a result of the accumulation of omega-6 fatty acids previously observed in this patient population. It is hypothesized that the administration of omega-3 fatty acids in combination with l-carnitine would increase CPT-I activity and improve chronic fatigue syndrome symptomology.

© 2011 The Association for the Publication of the Journal of Internal Medicine.

 

Source: Reuter SE, Evans AM. Long-chain acylcarnitine deficiency in patients with chronic fatigue syndrome. Potential involvement of altered carnitine palmitoyltransferase-I activity. J Intern Med. 2011 Jul;270(1):76-84. doi: 10.1111/j.1365-2796.2010.02341.x. Epub 2011 Jan 19. https://www.ncbi.nlm.nih.gov/pubmed/21205027