Reliability and validity of Short Form 36 Version 2 to measure health perceptions in a sub-group of individuals with fatigue

Abstract:

PURPOSE: To determine the validity and reliability of Short Form 36 Version 2 (SF36v2) in sub-groups of individuals with fatigue.

METHOD: Thirty subjects participated in this study, including n = 16 subjects who met case definition criteria for chronic fatigue syndrome (CFS) and n = 14 non-disabled sedentary matched control subjects. SF36v2 and Multidimensional Fatigue Inventory (MFI-20) were administered before two maximal cardiopulmonary exercise tests (CPETs) administered 24 h apart and an open-ended recovery questionnaire was administered 7 days after CPET challenge. The main outcome measures were self-reported time to recover to pre-challenge functional and symptom status, frequency of post-exertional symptoms and SF36v2 sub-scale scores.

RESULTS: Individuals with CFS demonstrated significantly lower SF36v2 and MFI-20 sub-scale scores prior to CPET. Between-group differences remained significant post-CPET, however, there were no significant group by test interaction effects. Subjects with CFS reported significantly more total symptoms (p < 0.001), as well as reports of fatigue (p < 0.001), neuroendocrine (p < 0.001), immune (p < 0.01), pain (p < 0.01) and sleep disturbance (p < 0.01) symptoms than control subjects as a result of CPET. Many symptom counts demonstrated significant relationships with SF36v2 sub-scale scores (p < 0.05). SF36v2 and MFI-20 sub-scale scores demonstrated significant correlations (p < 0.05). Various SF36v2 sub-scale scores demonstrated significant predictive validity to identify subjects who recovered from CPET challenge within 1 day and 7 days (p < 0.05). Potential floor effects were observed for both questionnaires for individuals with CFS.

CONCLUSION: Various sub-scales of SF36v2 demonstrated adequate reliability and validity for clinical and research applications. Adequacy of sensitivity to change of SF36v2 as a result of a fatiguing stressor should be the subject of additional study.

 

Source: Davenport TE, Stevens SR, Baroni K, Van Ness JM, Snell CR. Reliability and validity of Short Form 36 Version 2 to measure health perceptions in a sub-group of individuals with fatigue. Disabil Rehabil. 2011;33(25-26):2596-604. doi: 10.3109/09638288.2011.582925. Epub 2011 Jun 20. https://www.ncbi.nlm.nih.gov/pubmed/21682669

 

Increased tenderness in the left third intercostal space in adult patients with myalgic encephalomyelitis: a controlled study

Abstract:

A clinical sign has not thus far been associated with myalgic encephalomyelitis (ME). The present study involved systematic clinical examination that included inspection, palpation, percussion and auscultation of the thorax of 42 ME patients and 20 age-matched healthy controls while sitting. Left lateral third intercostal space tenderness was noted in 34 (81%) of the patients and in none of the controls, a difference that was highly statistically significant. This finding may be related to changes in lymphatic function and to the descending course of the thoracic duct. Further studies, preferably blinded and combined with appropriate imaging, are required.

 

Source: Puri BK, Gunatilake KD, Fernando KA, Gurusinghe AI, Agour M, Treasaden IH. Increased tenderness in the left third intercostal space in adult patients with myalgic encephalomyelitis: a controlled study. J Int Med Res. 2011;39(1):212-4. https://www.ncbi.nlm.nih.gov/pubmed/21672323

 

Mitochondrial enzymes discriminate between mitochondrial disorders and chronic fatigue syndrome

Abstract:

We studied the extent of mitochondrial involvement in chronic fatigue syndrome (CFS) and investigated whether measurement of mitochondrial respiratory chain complex (RCC) activities discriminates between CFS and mitochondrial disorders.

Mitochondrial content was decreased in CFS compared to healthy controls, whereas RCC activities corrected for mitochondrial content were not. Conversely, mitochondrial content did not discriminate between CFS and two groups of mitochondrial disorders, whereas ATP production rate and complex I, III and IV activity did, all with higher activities in CFS. We conclude that the ATP production rate and RCC activities can reliably discriminate between mitochondrial disorders and CFS.

Copyright © 2011 Elsevier B.V. and Mitochondria Research Society. All rights reserved.

 

Source: Smits B, van den Heuvel L, Knoop H, Küsters B, Janssen A, Borm G, Bleijenberg G, Rodenburg R, van Engelen B. Mitochondrial enzymes discriminate between mitochondrial disorders and chronic fatigue syndrome. Mitochondrion. 2011 Sep;11(5):735-8. doi: 10.1016/j.mito.2011.05.005. Epub 2011 Jun 2. https://www.ncbi.nlm.nih.gov/pubmed/21664495

 

Chronic fatigue syndrome in the media: a content analysis of newspaper articles

Abstract:

OBJECTIVES: Although cognitive behavioural therapy and graded exercise treatment are recognized evidence-based treatments for chronic fatigue syndrome/myalgic encephalomyelitis (ME), their use is still considered controversial by some patient groups. This debate has been reflected in the media, where many patients gather health information. The aim of this study was to examine how treatment for chronic fatigue syndrome/ME is described in the newspaper media.

DESIGN: Content analysis of newspaper articles.

SETTING: The digitalized media archive Atekst was used to identify Norwegian newspaper articles where chronic fatigue syndrome/ME was mentioned.

PARTICIPANTS: Norwegian newspaper articles published over a 20-month period, from 1 January 2008 to 31 August 2009.

MAIN OUTCOME MEASURES: Statements regarding efficiency of various types of treatment for chronic fatigue syndrome/ME and the related source of the treatment advice. Statements were categorized as being either positive or negative towards evidence-based or alternative treatment.

RESULTS: One hundred and twenty-two statements regarding treatment of chronic fatigue syndrome/ME were identified among 123 newspaper articles. The most frequent statements were positive statements towards alternative treatment Lightning Process (26.2%), negative statements towards evidence-based treatments (22.1%), and positive statements towards other alternative treatment interventions (22.1%). Only 14.8% of the statements were positive towards evidence-based treatment. Case-subjects were the most frequently cited sources, accounting for 35.2% of the statements, followed by physicians and the Norwegian ME association.

CONCLUSIONS: Statements regarding treatment for chronic fatigue syndrome/ME in newspapers are mainly pro-alternative treatment and against evidence-based treatment. The media has great potential to influence individual choices. The unbalanced reporting of treatment options for chronic fatigue syndrome/ME in the media is potentially harmful.

 

Source: Knudsen AK, Omenås AN, Harvey SB, Løvvik CM, Lervik LV, Mykletun A. Chronic fatigue syndrome in the media: a content analysis of newspaper articles. JRSM Short Rep. 2011 May;2(5):42. doi: 10.1258/shorts.2011.011016. Epub 2011 May 25. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3105457/ (Full article)

 

No evidence of murine-like gammaretroviruses in CFS patients previously identified as XMRV-infected

Abstract:

Members of the gammaretroviruses–such as murine leukemia viruses (MLVs), most notably XMRV [xenotropic murine leukemia virus (X-MLV)-related virus–have been reported to be present in the blood of patients with chronic fatigue syndrome (CFS).

We evaluated blood samples from 61 patients with CFS from a single clinical practice, 43 of whom had previously been identified as XMRV-positive. Our analysis included polymerase chain reaction and reverse transcription polymerase chain reaction procedures for detection of viral nucleic acids and assays for detection of infectious virus and virus-specific antibodies.

We found no evidence of XMRV or other MLVs in these blood samples. In addition, we found that these gammaretroviruses were strongly (X-MLV) or partially (XMRV) susceptible to inactivation by sera from CFS patients and healthy controls, which suggested that establishment of a successful MLV infection in humans would be unlikely. Consistent with previous reports, we detected MLV sequences in commercial laboratory reagents. Our results indicate that previous evidence linking XMRV and MLVs to CFS is likely attributable to laboratory contamination.

Comment in: Prostate cancer: XMRV–contaminant, not cause? [Nat Rev Urol. 2011]

 

Source: Knox K, Carrigan D, Simmons G, Teque F, Zhou Y, Hackett J Jr, Qiu X, Luk KC, Schochetman G, Knox A, Kogelnik AM, Levy JA. No evidence of murine-like gammaretroviruses in CFS patients previously identified as XMRV-infected. Science. 2011 Jul 1;333(6038):94-7. doi: 10.1126/science.1204963. Epub 2011 May 31. https://www.ncbi.nlm.nih.gov/pubmed/21628393

 

Chronic fatigue syndrome: labels, meanings and consequences

Abstract:

In this month’s issue, we report a survey of members of the Association of British Neurologists, which asked if they viewed chronic fatigue syndrome (CFS) as a neurological condition–84% of respondents did not. This is at odds with current classification in ICD-10. We discuss the difficulties of classifying CFS and myalgic encephalopmeylitis (ME), including historical and sociological factors, the pitfalls of the physical/psychological dichotomy and why classification matters to doctors and patients.

 

Source: Wojcik W, Armstrong D, Kanaan R. Chronic fatigue syndrome: labels, meanings and consequences. J Psychosom Res. 2011 Jun;70(6):500-4. doi: 10.1016/j.jpsychores.2011.02.002. Epub 2011 Apr 9. https://www.ncbi.nlm.nih.gov/pubmed/21624573

 

Immunological abnormalities as potential biomarkers in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis

Abstract:

BACKGROUND: Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME) is characterised by severe prolonged fatigue, and decreases in cognition and other physiological functions, resulting in severe loss of quality of life, difficult clinical management and high costs to the health care system. To date there is no proven pathomechanism to satisfactorily explain this disorder. Studies have identified abnormalities in immune function but these data are inconsistent. We investigated the profile of markers of immune function (including novel markers) in CFS/ME patients.

METHODS: We included 95 CFS/ME patients and 50 healthy controls. All participants were assessed on natural killer (NK) and CD8(+) T cell cytotoxic activities, Th1 and Th2 cytokine profile of CD4(+) T cells, expression of vasoactive intestinal peptide receptor 2 (VPACR2), levels of NK phenotypes (CD56(bright) and CD56(dim)) and regulatory T cells expressing FoxP3 transcription factor.

RESULTS: Compared to healthy individuals, CFS/ME patients displayed significant increases in IL-10, IFN-γ, TNF-α, CD4(+)CD25(+) T cells, FoxP3 and VPACR2 expression. Cytotoxic activity of NK and CD8(+) T cells and NK phenotypes, in particular the CD56(bright) NK cells were significantly decreased in CFS/ME patients. Additionally granzyme A and granzyme K expression were reduced while expression levels of perforin were significantly increased in the CFS/ME population relative to the control population. These data suggest significant dysregulation of the immune system in CFS/ME patients.

CONCLUSIONS: Our study found immunological abnormalities which may serve as biomarkers in CFS/ME patients with potential for an application as a diagnostic tool.

 

Source: Brenu EW, van Driel ML, Staines DR, Ashton KJ, Ramos SB, Keane J, Klimas NG, Marshall-Gradisnik SM. Immunological abnormalities as potential biomarkers in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis. J Transl Med. 2011 May 28;9:81. doi: 10.1186/1479-5876-9-81. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3120691/ (Full article)

 

Evidence for a heritable predisposition to Chronic Fatigue Syndrome

Abstract:

BACKGROUND: Chronic Fatigue Syndrome (CFS) came to attention in the 1980s, but initial investigations did not find organic causes. Now decades later, the etiology of CFS has yet to be understood, and the role of genetic predisposition in CFS remains controversial. Recent reports of CFS association with the retrovirus xenotropic murine leukemic virus-related virus (XMRV) or other murine leukemia related retroviruses (MLV) might also suggest underlying genetic implications within the host immune system.

METHODS: We present analyses of familial clustering of CFS in a computerized genealogical resource linking multiple generations of genealogy data with medical diagnosis data of a large Utah health care system. We compare pair-wise relatedness among cases to expected relatedness in the Utah population, and we estimate risk for CFS for first, second, and third degree relatives of CFS cases.

RESULTS: We observed significant excess relatedness of CFS cases compared to that expected in this population. Significant excess relatedness was observed for both close (p <0.001) and distant relationships (p = 0.010). We also observed significant excess CFS relative risk among first (2.70, 95% CI: 1.56-4.66), second (2.34, 95% CI: 1.31-4.19), and third degree relatives (1.93, 95% CI: 1.21-3.07).

CONCLUSIONS: These analyses provide strong support for a heritable contribution to predisposition to Chronic Fatigue Syndrome. A population of high-risk CFS pedigrees has been identified, the study of which may provide additional understanding.

 

Source: Albright F, Light K, Light A, Bateman L, Cannon-Albright LA. Evidence for a heritable predisposition to Chronic Fatigue Syndrome. BMC Neurol. 2011 May 27;11:62. doi: 10.1186/1471-2377-11-62. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3128000/ (Full article)

 

The functional status and well being of people with myalgic encephalomyelitis/chronic fatigue syndrome and their carers

Abstract:

BACKGROUND: Diagnosis of myalgic encephalomyelitis/chronic fatigue syndrome or ME/CFS is largely based on clinical history, and exclusion of identifiable causes of chronic fatigue. Characterization of cases and the impact of interventions have been limited due to clinical heterogeneity and a lack of reliable biomarkers for diagnosis and outcome measures. People with ME/CFS (PWME) often report high levels of disability, which are difficult to measure objectively. The well being of family members and those who care for PWME are also likely to be affected. This study aimed to investigate the functional status and well being of PWME and their lay carers, and to compare them with people with other chronic conditions.

METHODS: We used a cross sectional design to study 170 people aged between 18 and 64 years with well characterized ME/CFS, and 44 carers, using SF-36 v2™. Mean physical and mental domains scores (scales and component summaries) were calculated and compared internally and externally with reference standards for the general population and for population groups with 10 chronic diseases.

: SF-36 scores in PWME were significantly reduced, especially within the physical domain (mean norm-based Physical Component Summary (PCS) score = 26.8), but also within the mental domain (mean norm-based score for Mental Component Summary (MCS) = 34.1). The lowest and highest scale scores were for “Role-Physical” (mean = 25.4) and “Mental Health” (mean = 36.7) respectively. All scores were in general lower than those for the general population and diseased-specific norms for other diseases. Carers of those with ME/CFS tended to have low scores in relation to population norms, particularly within the mental domain (mean = 45.4).

CONCLUSIONS: ME/CFS is disabling and has a greater impact on functional status and well being than other chronic diseases such as cancer. The emotional burden of ME/CFS is felt by lay carers as well as by people with ME/CFS. We suggest the use of generic instruments such as SF-36, in combination of other objective outcome measurements, to describe patients and assess treatments.

 

Source: Nacul LC, Lacerda EM, Campion P, Pheby D, Drachler Mde L, Leite JC, Poland F, Howe A, Fayyaz S, Molokhia M. The functional status and well being of people with myalgic encephalomyelitis/chronic fatigue syndrome and their carers. BMC Public Health. 2011 May 27;11:402. doi: 10.1186/1471-2458-11-402. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3123211/ (Full article)

 

Chronic fatigue syndrome

Abstract:

Chronic fatigue syndrome (CFS) is defined by a profound, debilitating fatigue, lasting for at least 6 months and resulting in a substantial reduction of occupational, personal, social and educational status. CFS is a relatively poorly recognized clinical entity, although everyday experience shows that there are many patients with CFS symptoms.

The incidence and prevalence of CFS remain unknown in most countries; however, the working population is most affected with predominantly female patients in generative period. Although, CFS was first mentioned four centuries ago, mysterious aethiopathogensis of CFS still intrigues scientists as hundreds of studies are still published every year on the subject. About 80 different aetiological CFS factors are mentioned, which can be classified into five basic groups: genetics, immunology, infectious diseases, endocrinology and neuropsychiatry-psychology.

Even today the condition is passed established based on the diagnosis by exclusion of organic and psychiatric disorders, which demands a multidisciplinary approach. As the syndrome is often misdiagnosed and mistreated, self-medication is not uncommon in CFS patients’. In addition, such patients usually suffer for years tolerating severe fatigue. Thus, at the moment there are three priorities regarding CFS; understanding pathogenesis, development of diagnostic tests and creating efficient treatment program.

 

Source: Brkić S, Tomić S, Ruzić M, Marić D. Chronic fatigue syndrome. Srp Arh Celok Lek. 2011 Mar-Apr;139(3-4):256-61. https://www.ncbi.nlm.nih.gov/pubmed/21618868