Chronic fatigue syndrome in male Gulf war veterans and civilians: a further test of the single syndrome hypothesis

Abstract:

Different modes of fatigue onset in male Gulf War veterans versus male civilians raise the possibility that chronic fatigue syndrome (CFS) may not be a single disease entity. We addressed this issue by comparing 45 male veterans with CFS to 84 male civilians who satisfied identical case criteria. All were evaluated for fibromyalgia (FM), multiple chemical sensitivity and psychiatric comorbidity. CFS was more likely to present in a sudden flu-like manner in civilians than veterans (p < .01) and comorbid FM was more prevalent in civilians (p < .01). These findings question the assumption that all patients with CFS suffer from the same underlying disorder.

 

Source: Ciccone DS, Weissman L, Natelson BH. Chronic fatigue syndrome in male Gulf war veterans and civilians: a further test of the single syndrome hypothesis. J Health Psychol. 2008 May;13(4):529-36. Doi: 10.1177/1359105308088525. https://www.ncbi.nlm.nih.gov/pubmed/18420761

 

Dynamics of sleep stage transitions in healthy humans and patients with chronic fatigue syndrome

Abstract:

Physiological and/or pathological implications of the dynamics of sleep stage transitions have not, to date, been investigated. We report detailed duration and transition statistics between sleep stages in healthy subjects and in others with chronic fatigue syndrome (CFS); in addition, we also compare our data with previously published results for rats.

Twenty-two healthy females and 22 female patients with CFS, characterized by complaints of unrefreshing sleep, underwent one night of polysomnographic recording. We find that duration of deep sleep (stages III and IV) follows a power-law probability distribution function; in contrast, stage II sleep durations follow a stretched exponential and stage I, and REM sleep durations follow an exponential function. These stage duration distributions show a gradually increasing departure from the exponential form with increasing depth of sleep toward a power-law type distribution for deep sleep, suggesting increasing complexity of regulation of deeper sleep stages. We also find a substantial number of REM to non-REM sleep transitions in humans, while this transition is reported to be virtually nonexistent in rats.

The relative frequency of this REM to non-REM sleep transition is significantly lower in CFS patients than in controls, resulting in a significantly greater relative transition frequency of moving from both REM and stage I sleep to awake. Such an alteration in the transition pattern suggests that the normal continuation of sleep in light or REM sleep is disrupted in CFS. We conclude that dynamic transition analysis of sleep stages is useful for elucidating yet-to-be-determined human sleep regulation mechanisms with pathophysiological implications.

 

Source: Kishi A, Struzik ZR, Natelson BH, Togo F, Yamamoto Y. Dynamics of sleep stage transitions in healthy humans and patients with chronic fatigue syndrome. Am J Physiol Regul Integr Comp Physiol. 2008 Jun;294(6):R1980-7. doi: 10.1152/ajpregu.00925.2007. Epub 2008 Apr 16. http://ajpregu.physiology.org/content/294/6/R1980.long

 

Contentious diseases–a medico-social phenomenon from an insurance medicine perspective

Abstract:

A group of illnesses that are difficult to assess objectively, comprising such conditions as fibromyalgia, chronic fatigue syndrome, attention-deficit hyperactivity disorder, whiplash injury, and last but not least a multitude of somatoform disorders, has become a growing concern to Western health care systems and insurance industries.

Thus far, the medical literature has failed to provide informative overviews of this group, which at first glance admittedly seems to be rather heterogeneous. If at all, the disorders have been grouped together under the term ,,controversial illnesses” to differentiate them from other diseases. The insurance industry – and claims departments, in particular – are increasingly having to deal with this rapidly growing phenomenon, which affects not only life business, but also health, worker’s compensation and motor third-party liability. When paying compensation and settling claims, insurers are often left with a feeling that the illness may have been ,,imaginary” or aggravated. Is there a common basis for this new disorder mega-trend – independent of the recognition of the conditions by medical associations?

This article aims at providing an overview of the common characteristics of the group of disorders, including a description of the key physical, psychological and social aspects. In particular, it is intended to deepen insurers’ understanding of the risks arising from social change. The article also examines the disorder prevalence in Western societies and the possible causes of the significant increase.

 

Source: Regenauer A. Contentious diseases–a medico-social phenomenon from an insurance medicine perspective. Versicherungsmedizin. 2008 Mar 1;60(1):3-7. [Article in German] https://www.ncbi.nlm.nih.gov/pubmed/18405228

 

Memory for fatigue in chronic fatigue syndrome: relationships to fatigue variability, catastrophizing, and negative affect

Abstract:

Fatigue in chronic fatigue syndrome (CFS) is usually assessed with retrospective measures rather than real-time momentary symptom assessments. In this study, the authors hypothesized that in participants with CFS, discrepancies between recalled and momentary fatigue would be related to catastrophizing, anxiety, and depression and to variability of momentary fatigue. They also expected that catastrophizing, anxiety, and depression would be associated with momentary fatigue. The authors asked 53 adults with CFS to carry electronic diaries for 3 weeks and record their experiences of momentary fatigue. The authors assessed participants’ fatigue recall with weekly ratings and administered questionnaires for catastrophizing, depression, and anxiety. Recall discrepancy was significantly related to the variability of momentary fatigue. In addition, catastrophizing, depression, and momentary fatigue were all significantly related to recall discrepancy. Catastrophizing, depression, anxiety, and momentary negative affect were all significantly associated with momentary fatigue. The findings suggest that momentary fatigue in patients with CFS is related to modifiable psychological factors.

 

Source: Sohl SJ, Friedberg F. Memory for fatigue in chronic fatigue syndrome: relationships to fatigue variability, catastrophizing, and negative affect. Behav Med. 2008 Spring;34(1):29-38. doi: 10.3200/BMED.34.1.29-38. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2567050/ (Full article)

 

Sexual dysfunction as related to severity of fatigue in women with CFS

Abstract:

To assess sexual function in women with chronic fatigue syndrome. The study included 27 women, aged 20 to 45 years, with chronic fatigue syndrome (CFS) and 15 healthy female controls. Sexual function was measured with the Golombok Rust Inventory of Sexual Satisfaction (GRISS) questionnaire and five clinical questions. In the patient group, total fatigue impact scale (FIS) score correlated with the GRISS satisfaction (r:-0.471, P < .005), avoidance (r: 0.632, P < .001) and sensuality (r: -0.445, P = .008) subscales. The GRISS satisfaction, avoidance, and sensuality subscale results and the fact of seeing the sexual act as a negative experience correlated with the intensity of fatigue in women with CFS.

 

Source: Blazquez A, Ruiz E, Vazquez A, de Sevilla TF, Garcia-Quintana A, Garcia-Quintana J, Alegre J. Sexual dysfunction as related to severity of fatigue in women with CFS. J Sex Marital Ther. 2008;34(3):240-7. doi: 10.1080/00926230701866232. https://www.ncbi.nlm.nih.gov/pubmed/18398762

 

Unravelling intracellular immune dysfunctions in chronic fatigue syndrome: interactions between protein kinase R activity, RNase L cleavage and elastase activity, and their clinical relevance

Abstract:

This study examined possible interactions between immunological abnormalities and symptoms in CFS. Sixteen CFS patients filled in a battery of questionnaires, evaluating daily functioning, and underwent venous blood sampling, in order to analyse immunological abnormalities.

Ribonuclease (RNase) L cleavage was associated with RNase L activity (rs=0.570; p=0.021), protein kinase R (PKR) (rs=0.716; p=0.002) and elastase activity (rs=0.500; p=0.049). RNase L activity was related to elastase (rs=0.547; p=0.028) and PKR activity (rs=0.625; p=0.010). RNase L activity (rs=0.535; p=0.033), elastase activity (rs=0.585; p=0.017) and RNase L cleavage (rs=0.521; p=0.038) correlated with daily functioning.

This study suggests that in CFS patients an increase in elastase activity and subsequent RNase L cleavage is accompanied by increased activity of both the PKR and RNase L enzymes. RNase L and elastase activity are related to daily functioning, thus evidence supporting the clinical importance of these immune dysfunctions in CFS patients was provided.

 

Source: Meeus M, Nijs J, McGregor N, Meeusen R, De Schutter G, Truijen S, Frémont M, Van Hoof E, De Meirleir K. Unravelling intracellular immune dysfunctions in chronic fatigue syndrome: interactions between protein kinase R activity, RNase L cleavage and elastase activity, and their clinical relevance. In Vivo. 2008 Jan-Feb;22(1):115-21. http://iv.iiarjournals.org/content/22/1/115.long (Full article)

 

Chronic fatigue syndrome: an approach combining self-management with graded exercise to avoid exacerbations

Abstract:

Controversy regarding the aetiology and treatment of patients with chronic fatigue syndrome continues among the medical professions. The Cochrane Collaboration advises practitioners to implement graded exercise therapy for patients with chronic fatigue syndrome using cognitive behavioural principles. Conversely, there is evidence that exercise can exacerbate symptoms in chronic fatigue syndrome, if too-vigorous exercise/activity promotes immune dysfunction, which in turn increases symptoms.

When designing and implementing an exercise programme for chronic fatigue syndrome it is important to be aware of both of these seemingly opposing viewpoints in order to deliver a programme with no detrimental effects on the pathophysiology of the condition.

Using evidence from both the biological and clinical sciences, this paper explains that graded exercise therapy for people with chronic fatigue syndrome can be undertaken safely with no detrimental effects on the immune system. Exercise programmes should be designed to cater for individual physical capabilities and should take into account the fluctuating nature of symptoms.

In line with cognitive behaviourally and graded exercise-based strategies, self-management for people with chronic fatigue syndrome involves encouraging patients to pace their activities and respect their physical and mental limitations, with the ultimate aim of improving their everyday functioning.

Comment in: Chronic fatigue syndrome. [J Rehabil Med. 2008]

 

Source: Nijs J, Paul L, Wallman K. Chronic fatigue syndrome: an approach combining self-management with graded exercise to avoid exacerbations. J Rehabil Med. 2008 Apr;40(4):241-7. Doi: 10.2340/16501977-0185. https://www.ncbi.nlm.nih.gov/pubmed/18382818

 

Alterations in diurnal salivary cortisol rhythm in a population-based sample of cases with chronic fatigue syndrome

Abstract:

OBJECTIVE: To examine diurnal salivary cortisol rhythms and plasma IL-6 concentrations in persons with chronic fatigue syndrome (CFS), persons not fulfilling a diagnosis of CFS (we term them cases with insufficient symptoms or fatigue, ISF) and nonfatigued controls (NF). Previous studies of CFS patients have implicated the hypothalamic-pituitary-adrenal axis and the immune system in the pathophysiology of CFS, although results have been equivocal.

METHODS: Twenty-eight people with CFS, 35 persons with ISF, and 39 NF identified from the general population of Wichita, Kansas, were admitted to a research ward for 2 days. Saliva was collected immediately on awakening (6:30 AM), at 08:00 AM, 12 noon, 4:00 PM, 8:00 PM and at bedtime (10:00 PM) and plasma was obtained at 7:30 AM. Salivary cortisol concentrations were assessed using radioimmunoassay, and plasma IL-6 was measured using sandwich enzyme-linked immunosorbent assay.

RESULTS: People with CFS demonstrated lower salivary cortisol concentrations in the morning and higher salivary cortisol concentrations in the evening compared with both ISF and NF groups indicating a flattening of the diurnal cortisol profile. Mean plasma IL-6 concentrations were highest in CFS compared with the other groups, although these differences were no longer significant after controlling for BMI. Attenuated decline of salivary cortisol concentrations across the day and IL-6 concentration were associated with fatigue symptoms in CFS.

CONCLUSIONS: These results suggest an altered diurnal cortisol rhythm and IL-6 concentrations in CFS cases identified from a population-based sample.

 

Source: Nater UM, Youngblood LS, Jones JF, Unger ER, Miller AH, Reeves WC, Heim C. Alterations in diurnal salivary cortisol rhythm in a population-based sample of cases with chronic fatigue syndrome. Psychosom Med. 2008 Apr;70(3):298-305. doi: 10.1097/PSY.0b013e3181651025. Epub 2008 Mar 31. https://www.ncbi.nlm.nih.gov/pubmed/18378875

 

Etiology of chronic fatigue syndrome: testing popular hypotheses using a national birth cohort study

Abstract:

OBJECTIVE: To review the etiology of chronic fatigue syndrome (CFS) and test hypotheses relating to immune system dysfunction, physical deconditioning, exercise avoidance, and childhood illness experiences, using a large prospective birth cohort.

METHODS: A total of 4779 participants from the Medical Research Council’s National Survey of Health and Development were prospectively followed for the first 53 years of their life with >20 separate data collections. Information was collected on childhood and parental health, atopic illness, levels of physical activity, fatigue, and participant’s weight and height at multiple time points. CFS was identified through self-report during a semistructured interview at age 53 years with additional case notes review.

RESULTS: Of 2983 participants assessed at age 53 years, 34 (1.1%, 95% Confidence Interval 0.8-1.5) reported a diagnosis of CFS. Those who reported CFS were no more likely to have suffered from childhood illness or atopy. Increased levels of exercise throughout childhood and early adult life and a lower body mass index were associated with an increased risk of later CFS. Participants who later reported CFS continued to exercise more frequently even after they began to experience early symptoms of fatigue.

CONCLUSIONS: Individuals who exercise frequently are more likely to report a diagnosis of CFS in later life. This may be due to the direct effects of this behavior or associated personality factors. Continuing to be active despite increasing fatigue may be a crucial step in the development of CFS.

 

Source: Harvey SB, Wadsworth M, Wessely S, Hotopf M. Etiology of chronic fatigue syndrome: testing popular hypotheses using a national birth cohort study. Psychosom Med. 2008 May;70(4):488-95. doi: 10.1097/PSY.0b013e31816a8dbc. Epub 2008 Mar 31. https://www.ncbi.nlm.nih.gov/pubmed/18378866

 

The awareness of chronic fatigue syndrome: a comparative study in Brazil and the United Kingdom

Abstract:

OBJECTIVE: While in many Western affluent countries there is widespread awareness of chronic fatigue syndrome (CFS), also known as myalgic encephalomyelitis (ME), little is known about the awareness of CFS/ME in low- and middle-income countries. We compared the awareness of CFS in Brazil and the United Kingdom.

METHODS: Recognition and knowledge of CFS were assessed among 120 Brazilian specialist doctors in two major university hospitals using a typical case vignette of CFS. We also surveyed 3914 and 2435 consecutive attenders in Brazilian and British primary care clinics, respectively, concerning their awareness of CFS.

RESULTS: When given a typical case vignette of CFS, only 30.8% [95% confidence interval (CI), 22.7-39.9%] of Brazilian specialist doctors mentioned chronic fatigue or CFS as a possible diagnosis, a proportion substantially lower than that observed in Western affluent countries. Similarly, only 16.2% (95% CI, 15.1-17.4%) of Brazilian primary care attenders were aware of CFS, in contrast to 55.1% (95% CI, 53.1-57.1%) of their British counterparts (P<.001). This difference remained highly significant after controlling for patients’ sociodemographic and socioeconomic characteristics (P<.001).

CONCLUSIONS: The awareness of CFS was substantially lower in Brazil than the United Kingdom. The observed difference may influence patients’ help-seeking behavior and both doctors’ and patients’ beliefs and attitudes in relation to fatigue-related syndromes. Attempts to promote the awareness of CFS should be considered in Brazil, but careful plans are required to ensure the delivery of sound evidence-based information.

 

Source: Cho HJ, Menezes PR, Bhugra D, Wessely S. The awareness of chronic fatigue syndrome: a comparative study in Brazil and the United Kingdom. J Psychosom Res. 2008 Apr;64(4):351-5. doi: 10.1016/j.jpsychores.2007.12.006. https://www.ncbi.nlm.nih.gov/pubmed/18374733