Chronic fatigue syndrome: illness severity, sedentary lifestyle, blood volume and evidence of diminished cardiac function

Abstract:

The study examined whether deficits in cardiac output and blood volume in a CFS (chronic fatigue syndrome) cohort were present and linked to illness severity and sedentary lifestyle. Follow-up analyses assessed whether differences in cardiac output levels between CFS and control groups were corrected by controlling for cardiac contractility and TBV (total blood volume).

The 146 participants were subdivided into two CFS groups based on symptom severity data, severe (n=30) and non-severe (n=26), and two healthy non-CFS control groups based on physical activity, sedentary (n=58) and non-sedentary (n=32). Controls were matched to CFS participants using age, gender, ethnicity and body mass. Echocardiographic measures indicated that the severe CFS participants had 10.2% lower cardiac volume (i.e. stroke index and end-diastolic volume) and 25.1% lower contractility (velocity of circumferential shortening corrected by heart rate) than the control groups. Dual tag blood volume assessments indicated that the CFS groups had lower TBV, PV (plasma volume) and RBCV (red blood cell volume) than control groups. Of the CFS subjects with a TBV deficit (i.e. > or = 8% below ideal levels), the mean+/-S.D. percentage deficit in TBV, PV and RBCV were -15.4+/-4.0, -13.2+/-5.0 and -19.1+/-6.3% respectively. Lower cardiac volume levels in CFS were substantially corrected by controlling for prevailing TBV deficits, but were not affected by controlling for cardiac contractility levels.

Analyses indicated that the TBV deficit explained 91-94% of the group differences in cardiac volume indices. Group differences in cardiac structure were offsetting and, hence, no differences emerged for left ventricular mass index. Therefore the findings indicate that lower cardiac volume levels, displayed primarily by subjects with severe CFS, were not linked to diminished cardiac contractility levels, but were probably a consequence of a co-morbid hypovolaemic condition. Further study is needed to address the extent to which the cardiac and blood volume alterations in CFS have physiological and clinical significance.

Comment in: Chronic fatigue syndrome: comments on deconditioning, blood volume and resulting cardiac function. [Clin Sci (Lond). 2009]

 

Source: Hurwitz BE, Coryell VT, Parker M, Martin P, Laperriere A, Klimas NG, Sfakianakis GN, Bilsker MS. Chronic fatigue syndrome: illness severity, sedentary lifestyle, blood volume and evidence of diminished cardiac function. Clin Sci (Lond). 2009 Oct 19;118(2):125-35. doi: 10.1042/CS20090055. https://www.ncbi.nlm.nih.gov/pubmed/19469714

 

Chronic fatigue syndrome combines increased exercise-induced oxidative stress and reduced cytokine and Hsp responses

Abstract:

OBJECTIVES: As heat shock proteins (Hsp) protect the cells against the deleterious effects of oxidative stress, we hypothesized that Hsp expression might be reduced in patients suffering from chronic fatigue syndrome (CFS) who present an accentuated exercise-induced oxidative stress.

DESIGN: This case-control study compared nine CFS patients to a gender-, age- and weight-matched control group of nine healthy sedentary subjects.

INTERVENTIONS: All subjects performed an incremental cycling exercise continued until exhaustion. We measured ventilation and respiratory gas exchange and evoked compound muscle potential (M-wave) recorded from vastus lateralis. Repetitive venous blood sampling allowed measurements of two markers of oxidative stress [thiobarbituric acid reactive substances (TBARS) and reduced ascorbic acid (RAA)], two cytokines (IL-6 and TNF-alpha) and two Hsp (Hsp27 and Hsp70) at rest, during maximal exercise and the 60-min recovery period.

RESULTS: Compared with controls, resting CFS patients had low baseline levels of RAA and Hsp70. Their response to maximal exercise associated (i) M-wave alterations indicating reduced muscle membrane excitability, (ii) early and accentuated TBARS increase accompanying reduced changes in RAA level, (iii) absence of significant increase in IL-6 and TNF-alpha, and (iv) delayed and marked reduction of Hsp27 and Hsp70 variations. The post-exercise increase in TBARS was accentuated in individuals having the lowest variations of Hsp27 and Hsp70.

CONCLUSIONS: The response of CFS patients to incremental exercise associates a lengthened and accentuated oxidative stress, which might result from delayed and insufficient Hsp production.

 

Source: Jammes Y, Steinberg JG, Delliaux S, Brégeon F.Chronic fatigue syndrome combines increased exercise-induced oxidative stress and reduced cytokine and Hsp responses. J Intern Med. 2009 Aug;266(2):196-206. doi: 10.1111/j.1365-2796.2009.02079.x. Epub 2009 May 19. https://www.ncbi.nlm.nih.gov/pubmed/19457057

 

Anxiety in children with CFS/ME

Abstract:

Anxiety symptoms are commonly described in children with chronic fatigue syndrome or myalgic encephalopathy (CFS/ME) but to date there has been little information on the type of anxiety children experience or the relationship between anxiety and school attendance, disability or fatigue.

The aim of this study was to first describe the prevalence and type of anxiety symptoms in children with CFS/ME compared with a normal European population, and secondly to investigate the association of anxiety symptoms with age, gender, school attendance, fatigue, and physical function in paediatric CFS/ME.

Data were prospectively collected on children and young people with CFS/ME referred to a large specialist CFS/ME service. One hundred and sixty-four children with CFS/ME had complete data for the Spence Children’s Anxiety Scale. Teenage girls had the highest rates of total anxiety symptoms with 38% (95% CI 27-49) over the cut off (top 10% of normal European population) and significantly higher rates of symptoms in each subscale.

Younger girls were more likely to score over the cut off in separation anxiety (37%, 19-40) and social phobia (39%, 25-47). There was no evidence of association between total anxiety symptoms and: time at school, time to assessment, pain or age. Associations with fatigue and physical function were attenuated when adjusted for other variables. Although anxiety symptoms are high in CFS/ME, particularly in teenage girls, it does not appear to be associated with school attendance or other measures of disability. Separation anxiety and social phobia were the most clearly elevated in paediatric CFS/ME.

 

Source: Crawley E, Hunt L, Stallard P. Anxiety in children with CFS/ME. Eur Child Adolesc Psychiatry. 2009 Nov;18(11):683-9. doi: 10.1007/s00787-009-0029-4. Epub 2009 May 19. https://www.ncbi.nlm.nih.gov/pubmed/19452195

 

An investigation into the cognitive deficits associated with chronic fatigue syndrome

Abstract:

This study addresses, among other things, the debate as to whether cognitive deficits do occur with a diagnosis of Chronic Fatigue Syndrome (CFS). Previous studies have indicated a potential mismatch between subjective patient ratings of impairment and clinical assessment.

In an attempt to tackle some of the methodological problems faced by previous research in this field, this study recruited a large sample of CFS patients where adequate diagnosis had been made and administered an extensive battery of measures. In doing so this study was able to replicate previous published evidence of clear cognitive impairment in this group and demonstrate also that these deficits occurred independent of psychopathology.

The conclusion drawn is that cognitive impairments can be identified if appropriate measures are used. Furthermore, the authors have shown that performance changes in these measures have been used to assess both efficacy of a treatment regime and rates of recovery.

 

Source: Thomas M, Smith A. An investigation into the cognitive deficits associated with chronic fatigue syndrome. Open Neurol J. 2009 Feb 27;3:13-23. doi: 10.2174/1874205X00903010013. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2682840/ (Full article)

 

A comparison of patients with chronic fatigue syndrome in two “ideologically” contrasting clinics

Abstract:

Aim of the present study was to compare chronic fatigue syndrome (CFS) patients, attending 2 “ideologically” contrasting clinics for CFS, on various patient and illness characteristics. Fifty-nine CFS patients of each clinic, located in Leuven and Brussels (Belgium), participated. Patients did not differ with regard to age, levels of fatigue, psychopathology, and self-efficacy. However, patients from the psychosocially-oriented clinic had a lower level of education, reported more progressive illness onset, and attributed their illness more to psychological causes.

Patients in the biologically-oriented clinic reported more pain, and showed higher levels of social functioning, motivation and vitality, as well as fewer limitations related to emotional problems. It is concluded that CFS patients attending the 2 clinics could not be distinguished along dualistic biological/psychosocial lines, but those reporting sudden illness onset and making somatic attributions were more likely to be represented in the biologically-oriented clinic.

 

Source: Van Houdenhove B, Van Hoof E, Becq K, Kempke S, Luyten P, De Meirleir K.A comparison of patients with chronic fatigue syndrome in two “ideologically” contrasting clinics. J Nerv Ment Dis. 2009 May;197(5):348-53. doi: 10.1097/NMD.0b013e3181a2081f. https://www.ncbi.nlm.nih.gov/pubmed/19440108

 

Chronic fatigue syndrome and mitochondrial dysfunction

Abstract:

This study aims to improve the health of patients suffering from chronic fatigue syndrome (CFS) by interventions based on the biochemistry of the illness, specifically the function of mitochondria in producing ATP (adenosine triphosphate), the energy currency for all body functions, and recycling ADP (adenosine diphosphate) to replenish the ATP supply as needed.

Patients attending a private medical practice specializing in CFS were diagnosed using the Centers for Disease Control criteria. In consultation with each patient, an integer on the Bell Ability Scale was assigned, and a blood sample was taken for the “ATP profile” test, designed for CFS and other fatigue conditions. Each test produced 5 numerical factors which describe the availability of ATP in neutrophils, the fraction complexed with magnesium, the efficiency of oxidative phosphorylation, and the transfer efficiencies of ADP into the mitochondria and ATP into the cytosol where the energy is used. With the consent of each of 71 patients and 53 normal, healthy controls the 5 factors have been collated and compared with the Bell Ability Scale.

The individual numerical factors show that patients have different combinations of biochemical lesions. When the factors are combined, a remarkable correlation is observed between the degree of mitochondrial dysfunction and the severity of illness (P<0.001). Only 1 of the 71 patients overlaps the normal region.

The “ATP profile” test is a powerful diagnostic tool and can differentiate patients who have fatigue and other symptoms as a result of energy wastage by stress and psychological factors from those who have insufficient energy due to cellular respiration dysfunction. The individual factors indicate which remedial actions, in the form of dietary supplements, drugs and detoxification, are most likely to be of benefit, and what further tests should be carried out.

 

Source: Myhill S, Booth NE, McLaren-Howard J. Chronic fatigue syndrome and mitochondrial dysfunction. Int J Clin Exp Med. 2009;2(1):1-16. Epub 2009 Jan 15. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2680051/ (Full article)

 

High slow-wave sleep and low-light sleep: chronic fatigue syndrome is not likely to be a primary sleep disorder

Abstract:

The status of chronic fatigue syndrome (CFS) is still under debate. Mainstream views still often consider it as an undetected primary sleep disorder or as the psychosomatic expression of a related anxiety or depression syndrome. Both primary sleep disorder and CFS are often related to unrefreshing sleep and affective daytime symptoms.

The present study compares nonrapid eye movement sleep distribution between patients with a primary sleep disorder and “pure” CFS patients without sleep or mood disorders. Intensity measures of affective symptoms are also analyzed. Sleep variables of 32 pure CFS (mean age, 41.9 +/- 8.7 years; 25 women), 30 Sleep Apnea Hypopnea Syndrome patients (mean age, 43.7 +/- 6.7 years; 13 women), and 14 healthy controls (mean age, 40.2 +/- 7.6 years; 9 women) were compared. Related affective symptoms were assessed using the self-reported Zung anxiety and depression scales.

The study confirms previous reports on increased slow-wave sleep in CFS patients. Both patient groups showed similar sleep duration and efficiency. Sleep efficiency was lower in both patient groups compared with controls. CFS patients showed a higher microarousal index than controls. Anxiety, but not depression symptoms were more intense in the CFS group. The distribution of nonrapid eye movement sleep in CFS differs sizeably from what can be observed in a primary sleep disorder.

 

Source: Neu D, Cappeliez B, Hoffmann G, Verbanck P, Linkowski P, Le Bon O. High slow-wave sleep and low-light sleep: chronic fatigue syndrome is not likely to be a primary sleep disorder. J Clin Neurophysiol. 2009 Jun;26(3):207-12. doi: 10.1097/WNP.0b013e3181a1841b. https://www.ncbi.nlm.nih.gov/pubmed/19424087

 

Cognitive behavioural therapy and psycho-education for chronic fatigue syndrome in young people: reflections from the families’ perspective

Abstract:

OBJECTIVES: Recent trials have produced optimistic results for family-focussed cognitive behavioural therapy (CBT) for chronic fatigue syndrome (CFS) in young people. This study sought to examine the under-researched question of the views and experiences of patients and families who take part.

DESIGN: Semi-structured interviews and qualitative analysis were chosen in order to address clients’ perspectives in depth.

METHODS: Sixteen young people and sixteen parents who participated in a trial of CBT versus psycho-education (PE) for CFS were interviewed. Key themes were discerned using inductive thematic analysis.

RESULTS: Most families had low expectations of a cure but hope for improvement. Generally speaking, participants found both CBT and PE acceptable and helpful. Behavioural aspects of CBT (e.g. goal-setting, graded activity) were found helpful. The opportunity to gain support, recognition and validation was important. Cognitive elements of therapy were sometimes deemed inappropriate and some felt emotional aspects of CFS were not adequately addressed. Participants were ambivalent towards the extent of family involvement. Negative experiences related to the therapy setting and feeling inappropriately labeled. Most participants felt therapy was a stepping-stone towards normal life, although many felt recovery was incomplete. Very few differences were found between themes from CBT and PE participants. A notable exception was that every young person who experienced CBT described therapy as helpful, whereas the participants who strongly opposed the therapy approach had all experienced PE.

CONCLUSIONS: The detailed insights regarding families’ therapy experiences suggest areas of improvement for service delivery and topics for further investigation.

 

Source: Dennison L, Stanbrook R, Moss-Morris R, Yardley L, Chalder T. Cognitive behavioural therapy and psycho-education for chronic fatigue syndrome in young people: reflections from the families’ perspective. Br J Health Psychol. 2010 Feb;15(Pt 1):167-83. doi: 10.1348/135910709X440034. Epub 2009 May 6. https://www.ncbi.nlm.nih.gov/pubmed/19422732

 

Plasma IL-6, its soluble receptors and F2-isoprostanes at rest and during exercise in chronic fatigue syndrome

Abstract:

The aim of the current study was to investigate the levels of interleukin-6 (IL-6), its soluble receptors (sIL-6R and sgp130) and F(2)-isoprostanes, at rest and during exercise, in patients with chronic fatigue syndrome (CFS).

Six male CFS patients and six healthy controls performed an incremental exercise test to exhaustion and a submaximal exercise bout to exhaustion. Blood samples taken in the submaximal test at rest, immediately post-exercise and 24 h post-exercise were analyzed for IL-6, sIL-6R, sgp130 and F(2)-isoprostanes. A further 33 CFS and 33 healthy control participants gave a resting blood sample for IL-6 and sIL-6R measurement.

During the incremental exercise test only power output at the lactate threshold was lower (P<0.05) in the CFS group. F(2)-isoprostanes were higher (P<0.05) in CFS patients at rest and this difference persisted immediately and 24 h post-exercise. The exercise study found no differences in IL-6, sIL-6R or sgp130 at any time point between groups. In the larger resting group, there were no differences in IL-6 and sIL-6R between CFS and control groups. This investigation has demonstrated that patients with CFS do not have altered plasma levels of IL-6, sIL-6R or sgp130 either at rest or following exercise. F(2)-isoprostanes, however, were consistently higher in CFS patients.

 

Source: Robinson M, Gray SR, Watson MS, Kennedy G, Hill A, Belch JJ, Nimmo MA. Plasma IL-6, its soluble receptors and F2-isoprostanes at rest and during exercise in chronic fatigue syndrome. Scand J Med Sci Sports. 2010 Apr;20(2):282-90. doi: 10.1111/j.1600-0838.2009.00895.x. Epub 2009 Apr 13. https://www.ncbi.nlm.nih.gov/pubmed/19422646

 

Psychiatric comorbidity in persons with chronic fatigue syndrome identified from the Georgia population

Abstract:

OBJECTIVE: To compare the prevalence of psychiatric disorders in persons with chronic fatigue syndrome (CFS) identified from the general population and a chronically ill group of people presenting with subsyndromic CFS-like illness (“insufficient symptoms or fatigue” (ISF)). Previous studies in CFS patients from primary and tertiary care clinics have found high rates of psychiatric disturbance, but this may reflect referral bias rather than true patterns of comorbidity with CFS.

METHODS: We used random digit dialing to identify unwell individuals. A detailed telephone interview identified those with CFS-like illness. These individuals participated in a 1-day clinical evaluation to confirm CFS or ISF status. We identified 113 cases of CFS and 264 persons with ISF. To identify current and lifetime psychiatric disorders, participants completed the Structured Clinical Interview for DSM-IV.

RESULTS: Sixty-four persons (57%) with CFS had at least one current psychiatric diagnosis, in contrast to 118 persons (45%) with ISF. One hundred one persons (89%) with CFS had at least one lifetime psychiatric diagnosis compared with 208 persons (79%) with ISF. Of note, only 11 persons (9.8%) with CFS and 25 persons (9.5%) with ISF reported having seen a mental healthcare specialist during the past 6 months.

CONCLUSIONS: Our findings indicate that current and lifetime psychiatric disorders commonly accompany CFS in the general population. Most CFS cases with comorbid psychiatric conditions had not sought appropriate help during the past 6 months. These results demonstrate an urgent need to address psychiatric disorders in the clinical care of CFS cases.

Comment in: Criteria used to define chronic fatigue syndrome questioned. [Psychosom Med. 2010]

 

Source: Nater UM, Lin JM, Maloney EM, Jones JF, Tian H, Boneva RS, Raison CL, Reeves WC, Heim C. Psychiatric comorbidity in persons with chronic fatigue syndrome identified from the Georgia population. Psychosom Med. 2009 Jun;71(5):557-65. doi: 10.1097/PSY.0b013e31819ea179. Epub 2009 May 4. https://www.ncbi.nlm.nih.gov/pubmed/19414619