Prospective observational study of treatments for unexplained chronic fatigue

Abstract:

BACKGROUND: Unexplained chronic fatigue is a frequent complaint in primary care. A prospective observational study design was used to evaluate whether certain commonly used therapies for unexplained chronic fatigue may be effective.

METHOD: Subjects with unexplained chronic fatigue of unknown etiology for at least 6 months were recruited from the Wisconsin Chronic Fatigue Syndrome Association, primary care clinics, and community chronic fatigue syndrome presentations. The primary outcome measure was change in a 5-question fatigue score from 6 months to 2 years. Self-reported interventions tested included prescribed medications, non-prescribed supplements and herbs, lifestyle changes, alternative therapies, and psychological support. Linear regression analysis was used to test the association of each therapy with the outcome measure after adjusting for statistically significant prognostic factors.

RESULTS: 155 subjects provided information on fatigue and treatments at baseline and follow-up. Of these subjects, 87% were female and 79% were middle-aged. The median duration of fatigue was 6.7 years. The percentage of users who found a treatment helpful was greatest for coenzyme Q10 (69% of 13 subjects), dehydroepiandrosterone (DHEA) (65% of 17 subjects), and ginseng (56% of 18 subjects). Treatments at 6 months that predicted subsequent fatigue improvement were vitamins (p = .08), vigorous exercise (p = .09), and yoga (p = .002). Magnesium (p = .002) and support groups (p = .06) were strongly associated with fatigue worsening from 6 months to 2 years. Yoga appeared to be most effective for subjects who did not have unclear thinking associated with the fatigue.

CONCLUSION: Certain alternative therapies for unexplained chronic fatigue, especially yoga, deserve testing in randomized controlled trials.

 

Source: Bentler SE, Hartz AJ, Kuhn EM. Prospective observational study of treatments for unexplained chronic fatigue. J Clin Psychiatry. 2005 May;66(5):625-32. http://www.ncbi.nlm.nih.gov/pubmed/15889950

 

The role of tryptophan in fatigue in different conditions of stress

Abstract:

Tryptophan is the precursor for the neurotransmitter 5-hydroxytryptamine (5-HT), which is involved in fatigue and sleep. It is present in bound and free from in the blood, where the concentration is controlled by albumin binding to tryptophan. An increase in plasma free tryptophan leads to an increased rate of entry of tryptophan into the brain. This should lead to a higher level of 5-HT which may cause central fatigue. Central fatigue is implicated in clinical conditions such as chronic fatigue syndrome and post-operative fatigue. Increased plasma free tryptophan leads to an increase in the plasma concentration ratio of free tryptophan to the branched chain amino acids (BCAA) which compete with tryptophan for entry into the brain across the blood-brain barrier.

The plasma concentrations of these amino acids were measured in chronic fatigue syndrome patients (CFS) before and after exercise (Castell et al., 1998), and in patients undergoing major surgery (Yamamoto et al., 1997). In the CFS patients, the pre-exercise concentration of plasma free tryptophan was higher than in controls (p < 0.05) but did not change during or after exercise. This might indicate an abnormally high level of brain 5-HT in CFS patients leading to persistent fatigue.

In the control group, plasma free tryptophan was increased after maximal exercise (p < 0.001), returning towards baseline levels 60 min later. The apparent failure of the CFS patients to change the plasma free tryptophan concentration or the free tryptophan/BCAA ratio during exercise may indicate increased sensitivity of brain 5-HT receptors, as has been demonstrated in other studies (Cleare et al., 1995).

In post-operative recovery after major surgery plasma free tryptophan concentrations were markedly increased compared with baseline levels; the plasma free tryptophan/BCAA concentration ratio was also increased after surgery. Plasma albumin concentrations were decreased after surgery: this may account for the increase in plasma free tryptophan levels.

Provision of BCAA has improved mental performance in athletes after endurance exercise (Blomstrand et al., 1995, 1997). It is suggested that BCAA supplementation may help to counteract the effects of an increase in plasma free tryptophan, and may thus improve the status of patients during or after some clinically stressful conditions.

 

Source: Castell LM, Yamamoto T, Phoenix J, Newsholme EA. The role of tryptophan in fatigue in different conditions of stress. Adv Exp Med Biol. 1999;467:697-704. http://www.ncbi.nlm.nih.gov/pubmed/10721121

 

Acute phase responses and cytokine secretion in chronic fatigue syndrome

Abstract:

This study addresses the hypothesis that clinical manifestations of chronic fatigue syndrome (CFS) are due in part to abnormal production of or sensitivity to cytokines such as interleukin-1beta (IL-1beta) and IL-6 under basal conditions or in response to a particular physical stress: 15 min of exercise consisting of stepping up and down on a platform adjusted to the height of the patella. The study involved 10 CFS patients and 11 age-, sex-, and activity-matched controls: of these, 6 patients and 4 controls were tested in both the follicular and the luteal phases of the menstrual cycle, and the remainder were tested in only one phase, for a total of 31 experimental sessions.

Prior to exercise, plasma concentrations of the acute phase reactant alpha2-macroglobulin were 29% higher in CFS patients (P < 0.008) compared to controls. Secretion of IL-6 was generally higher for CFS patients (approximately 38%), however, this difference was statistically significant only if all values over a 3-day period were analyzed by repeated-measures ANOVA (P = 0.035). IL-6 secretion correlated with plasma alpha2-macroglobulin in control subjects at rest (R = 0.767, P = 0.001).

Immediately after exercise, the CFS patients reported greater ratings of perceived exertion (P=0.027) compared to the healthy control subjects. Ratings of perceived exertion correlated with IL-1beta secretion by cells from healthy control subjects (R = 0.603, P = 0.022), but not from CFS patients, and IL-1beta secretion was not different between groups. Exercise induced a slight (< 12%) but significant (P = 0.006) increase in IL-6 secretion, but the responses of the CFS patients were not different than controls. Furthermore, no significant exercise-induced changes in body temperature or plasma alpha2-macroglobulin were observed.

These data indicate that under basal conditions, CFS is associated with increased IL-6 secretion which is manifested by chronically elevated plasma alpha2-macroglobulin concentrations. These modest differences suggest that cytokine dysregulation is not a singular or dominant factor in the pathogenesis of CFS.

 

Source: Cannon JG, Angel JB, Ball RW, Abad LW, Fagioli L, Komaroff AL. Acute phase responses and cytokine secretion in chronic fatigue syndrome. J Clin Immunol. 1999 Nov;19(6):414-21. http://www.ncbi.nlm.nih.gov/pubmed/10634215

 

Hormonal influences on stress-induced neutrophil mobilization in health and chronic fatigue syndrome

Abstract:

This investigation tested the hypotheses that women diagnosed with chronic fatigue syndrome (CFS) would exhibit significantly greater systemic indices of exercise-induced leukocyte mobilization and inflammation (neutrophilia, lactoferrin release, complement activation) than controls matched for age, weight, and habitual activity and that responses in the luteal phase of the menstrual cycle would be greater than in the follicular phase.

Subjects stepped up and down on a platform adjusted to the height of the patella for 15 min, paced by metronome. Blood samples were collected under basal conditions (the day before exercise) and following exercise for determination of circulating neutrophils and plasma concentrations of lactoferrin, C3a des arg, and creatine kinase. Complete, 24-hr urine collections were made for determination of cortisol excretion.

For all subjects, circulating neutrophil counts increased 33% (P < 0.0001) and lactoferrin increased 27% (P = 0.0006) after exercise, whereas plasma C3a des arg and creatine kinase did not increase. No indication of an exaggerated or excessive response was observed in the CFS patients compared to the controls.

In healthy women, circulating neutrophil numbers exhibited previously described relationships with physiological variables: basal neutrophil counts correlated with plasma progesterone concentrations (R = 0.726, P = 0.003) and the exercise-induced neutrophilia correlated with both urinary cortisol (R = 0.660, P = 0.007) and plasma creatine kinase (R = 0.523, P = 0.038) concentrations. These relationships were not observed in the CFS patients (R = 0.240, P = 0.370; R = 0.042, P = 0.892; and R = 0.293, P = 0.270; respectively).

These results suggest that normal endocrine influences on the circulating neutrophil pool may be disrupted in patients with CFS.

 

Source: Cannon JG, Angel JB, Abad LW, O’Grady J, Lundgren N, Fagioli L, Komaroff AL. Hormonal influences on stress-induced neutrophil mobilization in health and chronic fatigue syndrome. J Clin Immunol. 1998 Jul;18(4):291-8. http://www.ncbi.nlm.nih.gov/pubmed/9710746

 

Chronic fatigue syndrome: a literature review from a physiatric perspective

Abstract:

To examine the literature on chronic fatigue syndrome (CFS), especially as it relates to cognitive deficits and exercise, more than 200 articles related to CFS were selected from computer-based research as well as pertinent articles noted in the references of individual articles. All were relevant articles on CFS, although articles in a foreign language were excluded. CFS is a controversial diagnosis of exclusion, but certain subgroups do appear to exist. It may represent multiple diseases or multiple stages of the same disease. Although cognitive deficits are commonly reported, the measured impairments are relatively subtle and are in the area of complex information processing speed, or efficiency.

Magnetic resonance imaging, single-photon emission computer tomography, and neuroendocrine studies present preliminary evidence suggestive of the cerebral involvement primarily in the white matter. The weakness and fatigue may be the result of alterations in the central nervous system, not in the peripheral muscles. However, it is hard to separate the documented weakness and endurance deficits from deconditioning.

Autonomic symptoms such as orthostatic intolerance and a predisposition to neurally mediated syncope may be explained by cardiovascular deconditioning, a postviral idiopathic autonomic neuropathy, or both. The review points out the need for more carefully designed studies of CFS that focus on the relationship between neuropathology, psychopathology and neuropsychologic functioning. The role of exercise as a stimulus for exacerbation or in treatment needs to be further studied using clear diagnostic criteria as well as control groups that carefully match the activity level.

 

Source: Jain SS, DeLisa JA. Chronic fatigue syndrome: a literature review from a physiatric perspective. Am J Phys Med Rehabil. 1998 Mar-Apr;77(2):160-7. http://www.ncbi.nlm.nih.gov/pubmed/9558019

 

A case-control study to assess possible triggers and cofactors in chronic fatigue syndrome

Abstract:

PURPOSE: To assess possible triggers and cofactors for chronic fatigue syndrome (CFS) and to compare levels of selected cytokines between cases and an appropriately matched control group.

PATIENTS AND METHODS: We conducted a case-control study of 47 cases of CFS obtained through a regional CFS research program maintained at a tertiary care medical center. One age-, gender-, and neighborhood-matched control was identified for each case through systematic community telephone sampling. Standardized questionnaires were administered to cases and controls. Sera were assayed for transforming growth factor-beta (TGF-beta), interleukin-1 beta, interleukin-6, tumor necrosis factor-alpha, and antibody to Borrelia burgdorferi and Babesia microti.

RESULTS: Cases were more likely to have exercised regularly before illness onset than controls (67% versus 40%; matched odds ratio (MOR) = 3.4; 95% CI = 1.2 to 11.8; P = 0.02). Female cases were more likely to be nulliparous prior to onset of CFS than controls (51% versus 31%; MOR = 8.0; 95% CI = 1.03 to 170; P = 0.05). History of other major factors, including silicone-gel breast implants (one female case and one female control), pre-morbid history of depression (15% of cases, 11% of controls) and history of allergies (66% of cases, 51% of controls) were similar for cases and controls. However, cases were more likely to have a diagnosis of depression subsequent to their diagnosis of CFS compared to a similar time frame for controls (MOR = undefined; 95% CI lower bound = 2.5; P < 0.001). Positive antibody titers to B burgdorferi (one case and one control) and B microti (zero cases and two controls) were also similar.

CONCLUSIONS: Further investigation into the role of prior routine exercise as a cofactor for CFS is warranted. This study supports the concurrence of CFS and depression, although pre-morbid history of depression was similar for both groups.

Comment in: Etiology of chronic fatigue syndrome. [Am J Med. 1997]

 

Source: MacDonald KL, Osterholm MT, LeDell KH, White KE, Schenck CH, Chao CC, Persing DH, Johnson RC, Barker JM, Peterson PK. A case-control study to assess possible triggers and cofactors in chronic fatigue syndrome. Am J Med. 1996 May;100(5):548-54. http://www.ncbi.nlm.nih.gov/pubmed/8644768

 

Chronic fatigue syndrome–a review of the literature

Abstract:

Chronic fatigue syndrome is a clinical condition characterized by abnormal fatigue, subfebrile body temperature, sore throat, lymphadenopathy, arthralgia, myalgia and neuropsychiatric symptoms. Typically, the syndrome develops after a flu-like illness and is markedly exacerbated by exercise. The etiology is unknown and there is no single diagnostic test. The patients may have cognitive dysfunction, immunological and endocrinological abnormalities and abnormal mitochondria. Magnetic resonance imaging scans may show increased uptake of signals in the brain, and single photon emission computerized tomography reveals regional hypoperfusion of the brain. The author discusses similarities and distinctions between the syndrome and depression.

 

Source: Hamre HJ. Chronic fatigue syndrome–a review of the literature. Tidsskr Nor Laegeforen. 1995 Oct 10;115(24):3042-5. [Article in Norwegian] http://www.ncbi.nlm.nih.gov/pubmed/7570537

 

Chronic fatigue syndrome

Abstract:

Chronic fatigue syndrome (CFS) is defined by symptoms and diagnosed without any objective diagnostic tests. Risk factors for developing CFS may include infection, psychiatric disorders, and allergies. Modest dysfunction of multiple organ systems, including the immune, central nervous, endocrine, and muscular systems, have been identified in cases of CFS. Symptoms of various organic, psychiatric, and poorly understood disorders overlap those of CFS. There is no known cure for CFS; however, exercise, counseling, and medications may provide symptomatic relief.

 

Source: Klonoff DC. Chronic fatigue syndrome. Clin Infect Dis. 1992 Nov;15(5):812-23. http://www.ncbi.nlm.nih.gov/pubmed/1445980

 

Chronic fatigue syndrome: a joint paediatric-psychiatric approach

Comment on: Chronic fatigue syndrome: a joint paediatric-psychiatric approach. [Arch Dis Child. 1992]

 

SIR,-While agreeing that physical, psychological, and social factors must all be taken into account in the management of this complex and controversial syndrome I would disagree with Dr Margaret Vereker’s statement that no organic pathology can be detected to account for any of the symptoms. This conclusion has been made without reference to a number of research papers describing persisting viral infection, neuromuscular abnormalities in both structure and function, and immune system dysfunction.

Gow et al using polymerase chain reaction techniques, have been able to demonstrate the presence of enteroviral genome in muscle biopsies from a significant number of patients (53%) compared with controls (15%). None of the healthy control group in this study had evidence of viral particles in their muscle, this was only found in those with colonic or breast malignancies. Precisely what cytopathological effect this intracellular virus is having within muscle remains open to debate. However, Behan et al have published electron microscopic evidence of structural damage to the muscle mitochondria along with type II fibre atrophy; this is a finding which is not normally considered to be consistent with simple disuse.

You can read the rest of this letter here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1793782/pdf/archdisch00632-0102a.pdf

 

Source: Shepherd C. Chronic fatigue syndrome: a joint paediatric-psychiatric approach. Arch Dis Child. 1992 Nov;67(11):1410. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1793782/

 

Self help organization’s advice on myalgic encephalomyelitis

Comment on: Outcome in the chronic fatigue syndrome. [BMJ. 1992]

 

EDITOR,-I should like to assure Simon Wessely that neither the ME Association nor ME Action regards Michael Sharpe and colleagues’ findings in patients with chronic fatigue’ as another attack on its credibility. Nor do we see why the paper should “further sour relations between the organisations and the profession.”

As Wessely points out, the apparent relation between functional impairment and membership of a self help organisation at follow up does not mean that membership of such an organisation is responsible for the impairment. Aside from the fact that the study did not focus on myalgic encephalomyelitis, or on the work the ME Association does, Sharpe reassured us that there was no evidence of a causal relation between membership of a patient group and level of disability.

As regards the potential damage resulting from inaccurate information about myalgic encephalomyelitis, it is worth emphasising that the quote that illustrates this came from Nursing Standard and not from a magazine for patients. The British organisations have long been unhappy with the way the media have portrayed the illness and reviewed existing research, and it is often extremely difficult to get erroneous or biased information corrected. Sometimes we get a right of reply, but usually we don’t.

Finally, I wish to make clear that our current advice on exercise and stress is based on sound scientific research, the recommendations of our medical advisers, and 50 years’ experience. Since our aim is to help patients it would be ridiculous for us to ignore good research and to stick instead to outdated explanations, speculation, or even prejudice. No one gains from such a narrow minded approach, least of all us.

You can read the rest of this comment here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1883373/pdf/bmj00091-0063a.pdf

 

Source: Hume MC. Self help organization’s advice on myalgic encephalomyelitis. BMJ. 1992 Sep 12;305(6854):649. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1883373/