Somatomedin C (insulin-like growth factor I) levels in patients with chronic fatigue syndrome

Abstract:

Chronic fatigue syndrome is a disorder clinically quite similar to fibromyalgia syndrome, and it is of interest to examine if these two syndromes have pathogenetic as well as clinical features in common. Somatomedin C levels have been found to be lower in patients with fibromyalgia syndrome than in healthy controls. An attractive hypothesis relating sleep disturbance, altered somatotropic neuroendocrine function and fibromyalgia symptoms has been put forward as a plausible pathogenic mechanism for fibromyalgia syndrome. We therefore sought to investigate the level of somatomedin C in patients with chronic fatigue syndrome.

Somatomedin C levels were determined by radioimmunoassay in frozen serum specimens from 49 patients with CFS and 30 healthy blood donor control subjects of similar age and gender. Somatomedin C levels were higher in patients with CFS than in healthy control subjects (255.3 +/- 68.5 vs 211.9 +/- 76.2, P = 0.01). There was no effect of gender, use of nonsteroidal anti-inflammatory drugs or tricyclic drugs on levels of somatomedin C. There was a tendency for somatomedin C levels to fall with age.

In contrast to patients with fibromyalgia, in whom levels of somatomedin C have been found to be reduced, levels in patients with CFS were found to be elevated. Thus, despite the clinical similarities between these two conditions, they may be associated with different abnormalities of sleep and/or of the somatotropic neuroendocrine axis.

 

Source: Bennett AL, Mayes DM, Fagioli LR, Guerriero R, Komaroff AL. Somatomedin C (insulin-like growth factor I) levels in patients with chronic fatigue syndrome. J Psychiatr Res. 1997 Jan-Feb;31(1):91-6. http://www.ncbi.nlm.nih.gov/pubmed/9201651

 

Fibromyalgia and chronic fatigue syndrome: similarities and differences

Abstract:

CFS and FM are clinical conditions characterized by a variety of nonspecific symptoms including prominent fatigue, myalgia, and sleep disturbances. There are no diagnostic studies or widely accepted, pathogenic, explanatory models for either illness. Despite remarkably different diagnostic criteria, CFS and FM have many demographic and clinical similarities. More specifically, few differences exist in the domains of symptoms, examination findings, laboratory tests, functional status, psychosocial features, and psychiatric disorders. FM appears to represent an additional burden of suffering among those with CFS, however, underscoring the importance of recognizing concurrent CFS and FM. Further clarification of the similarities (and differences) between CFS and FM may be useful in studies of prognosis and help define subsets of patients who may benefit from specific therapeutic interventions.

 

Source: Buchwald D. Fibromyalgia and chronic fatigue syndrome: similarities and differences. Rheum Dis Clin North Am. 1996 May;22(2):219-43. http://www.ncbi.nlm.nih.gov/pubmed/9157484

 

Insulin-like growth factor-I (somatomedin C) levels in chronic fatigue syndrome and fibromyalgia

Abstract:

OBJECTIVE: Fibromyalgia (FM) and chronic fatigue syndrome (CFS) are similar conditions characterized by substantial fatigue, diffuse myalgias, sleep disturbances and a variety of other symptoms. Many patients with CFS meet strict criteria for FM. Recently, low insulin-like growth factor-I (IGF-I) levels have been demonstrated in patients with FM, suggesting that disruption of the growth hormone-IGF-I axis might explain the link between the muscle pain and poor sleep. Our goal was to determine whether IGF-I levels are decreased in CFS, and whether such findings are restricted to patients with concurrent FM.

METHODS: Radioimmunoassays were used to determine serum concentrations of IGF-I and its binding protein, (IGFBP-3). Subjects were 3 patients seen in a referral clinic for chronic fatigue: 15 patients with CFS, 15 who met criteria for both CFS and FM (CFS-FM), 27 with FM alone; and 15 healthy control (HC) subjects.

RESULTS: Patients and control subjects had similar demographic and clinical characteristics. No significant differences were observed among any of the 3 patient groups and control subjects in the mean concentration of either IGF-I or IGFBP-3. Likewise, the proportion of subjects with values above or below the laboratory’s reference range did not differ for IGF-I or IGFBP-3.

CONCLUSIONS: These findings suggest the disruption of the growth hormone-IGF-I axis previously demonstrated in FM patients is not evident in a referral population of patients with CFS, CFS-FM, or FM.

 

Source: Buchwald D, Umali J, Stene M. Insulin-like growth factor-I (somatomedin C) levels in chronic fatigue syndrome and fibromyalgia. J Rheumatol. 1996 Apr;23(4):739-42. http://www.ncbi.nlm.nih.gov/pubmed/8730136

 

Fibromyalgia, chronic fatigue syndrome, and myofascial pain

Abstract:

The prevalence of fibromyalgia in the general population was found to be 2% and increased with age. Multiple traumatic factors, including sexual and physical abuse, may be important initiating events. The most important pathophysiologic studies in fibromyalgia included evidence of altered blood flow to the brain and hypothalamic-pituitary-adrenal dysfunction. The prevalence of chronic fatigue syndrome is much less than that of fibromyalgia. Epidemiologic studies demonstrated that chronic fatigue and symptoms of fibromyalgia are distributed as continuous variables in the general population. No association between chronic fatigue and initial infections was seen in primary care practices.

 

Source: Goldenberg DL. Fibromyalgia, chronic fatigue syndrome, and myofascial pain. Curr Opin Rheumatol. 1996 Mar;8(2):113-23. http://www.ncbi.nlm.nih.gov/pubmed/8732795

 

High incidence of antibodies to 5-hydroxytryptamine, gangliosides and phospholipids in patients with chronic fatigue and fibromyalgia syndrome and their relatives: evidence for a clinical entity of both disorders

Abstract:

The fibromyalgia syndrome (FMS) is one of the most frequent rheumatic disorders showing a wide spectrum of different symptoms. An association with the chronic fatigue syndrome (CFS) has been discussed. Recently, a defined autoantibody pattern consisting of antibodies to serotonin (5-hydroxytryptamine, 5-HT), gangliosides and phospholipids was found in about 70% of the patients with FMS. We were therefore interested in seeing whether patients with CFS express similar humoral immunoreactivity.

Sera from 42 CFS patients were analysed by ELISA for these antibodies, and the results were compared with those previously observed in 100 FMS patients. 73% of the FMS and 62% of the CFS patients had antibodies to serotonin, and 71% or 43% to gangliosides, respectively. Antibodies to phospholipids could be detected in 54% of the FMS and 38% of the CFS patients. 49% of FMS and 17% of the CFS patients had all three antibodies in parallel, 70% and 55%, respectively had at least two of these antibody types. 21% of FMS and 29% of CFS patients were completely negative for these antibodies. Antibodies to 5-HT were closely related with FMS/CFS while antibodies to gangliosides and phospholipids could also be detected in other disorders.

The observation that family members of CFS and FMS patients also had these antibodies represents an argument in favour of a genetic predisposition. These data support the concept that FMS and CFS may belong to the same clinical entity and may manifest themselves as ‘psycho-neuro-endocrinological autoimmune diseases’.

 

Source: Klein R, Berg PA. High incidence of antibodies to 5-hydroxytryptamine, gangliosides and phospholipids in patients with chronic fatigue and fibromyalgia syndrome and their relatives: evidence for a clinical entity of both disorders. Eur J Med Res. 1995 Oct 16;1(1):21-6. http://www.ncbi.nlm.nih.gov/pubmed/9392689

 

Fibromyalgia syndrome and myofascial pain syndrome. Do they exist?

Abstract:

“It is in the healing business that the temptations of junk science are the strongest and the controls against it the weakest.” Despite their subjective nature, these syndromes (particularly MPS) have little reliability and validity, and advocates paint them as “objective.” Despite a legacy of poor-quality science, enthusiasts continue to cite small, methodologically flawed studies purporting to show biologic variables for these syndromes. Despite a wealth of traditional pain research, disciples continue to ignore the placebo effect, demonstrating a therapeutic hubris despite studies showing a dismal natural history for FS. In reviewing the literature on MPS and FS, F.M.R. Walshe’s sage words come to mind that the advocates of these syndromes are “better armed with technique than with judgment.” A sympathic observer might claim that labeling patients with monikers of nondiseases such as FS and MPS may not be such a bad thing. After all, there is still a stigma for psychiatric disease in our society, and even telling a sufferer that this plays only a partial role may put that patient on the defensive. Labeling may have iatrogenic consequences, however, particularly in the setting of the work place. Furthermore, review of a typical support group newsletter gives ipso facto proof of this noxious potential. The author of a flyer stuffed inside the newsletter complains that getting social security and disability benefits for “the invisible disability” can be “an uphill battle. But don’t loose (sic) hope.” Apparently the “seriousness of the condition” is not appreciated by the medical community at large, and “clinician bias may well be the largest threat,” according to Boston epidemiologist Dr. John Mason. Sufferers are urged to trek to their local medical library and pull four particular articles claiming FS patients have more “stress,” “daily hassles,” and difficulty working compared with arthritis patients. If articles can’t be located, patients are told to ask their lawyers for help. Although “Chronic Fatigue Syndrome” and FS are not considered by everyone to be the same malady, the “National Institute of Health (sic) has lumped these two conditions together. This could work in your favor.” (A U.S. political advocacy packet is available for $8, but a list of U.S. senators with Washington, DC addresses is freely provided.) These persons see themselves as victims worthy of a star appearance on the Oprah Winfrey show. A sense of bitterness emerges; one literally bed-bound Texas homemaker writes in Parents magazine that “Some doctors may give up and tell you that you are a hypochondriac.”(ABSTRACT TRUNCATED AT 400 WORDS)

 

Source: Bohr TW. Fibromyalgia syndrome and myofascial pain syndrome. Do they exist? Neurol Clin. 1995 May;13(2):365-84. http://www.ncbi.nlm.nih.gov/pubmed/7643831

 

Sleep disturbances and fatigue in women with fibromyalgia and chronic fatigue syndrome

Abstract:

OBJECTIVE: To determine the relationship between sleep disturbances and fatigue in women with fibromyalgia (FM) and those with chronic fatigue syndrome (CFS) and to assess whether any differences existed between the two groups.

DESIGN: Descriptive comparative.

SETTING: Community program on chronic fatigue syndrome and related disorders.

PARTICIPANTS: Sixty-three women who attended the program; 13 had CFS, and 50 had FM.

MAIN OUTCOME MEASURES: A moderately strong relationship between fatigue and sleepiness was found (r = .63, p < .01). Trouble staying asleep was the highest rated sleep disturbance, and fatigue was the most common subjective feeling reported. Women with CFS reported significantly more trouble staying asleep than women with FM, t(61) = 1.81, p < .03.

CONCLUSIONS: Data from this study support that women with FM and CFS encounter problems sleeping. Clinicians are encouraged to assess women with FM and CFS for their quality of sleep rather than amount of sleep. Researchers are encouraged to continue study of sleep disturbances in women with FM and CFS to improve understanding of the disturbances and to test the effectiveness of sleep interventions.

 

Source: Schaefer KM. Sleep disturbances and fatigue in women with fibromyalgia and chronic fatigue syndrome. J Obstet Gynecol Neonatal Nurs. 1995 Mar-Apr;24(3):229-33. http://www.ncbi.nlm.nih.gov/pubmed/7782955

 

Chronic fatigue syndrome and fibromyalgia

Comment on: Population study of tender point counts and pain as evidence of fibromyalgia. [BMJ. 1994]

 

EDITOR,-The relation between muscle pain, tender points, the chronic fatigue syndrome, and fibromyalgia are complex, and simplistic answers are inappropriate. In their paper Peter Croft and colleagues extrapolate their results to make two statements that I believe to be incorrect.’

My conclusions are based on 100 consecutive patients seen at Raigmore Hospital NHS Trust, who fulfilled precise definitions of the chronic fatigue syndrome 2 or fibromyalgia.3 The importance of this definition of the syndrome is that it has the same three month cut off for length of illness as fibromyalgia.3 Of the 100 patients, 99 (74 women, 25 men) had the chronic fatigue syndrome and one (a woman) had fibromyalgia. Of the patients with the chronic fatigue syndrome, 63 had muscle pain and 28 had tender points on examination, 23 had both, and five had no muscle pain but tender points. These results do not support the authors’ statement that the reason why fibromyalgia is not more common in Britain has been the acceptability of the chronic fatigue syndrome as an alternative diagnosis.

The authors also say that it is “inappropriate to define an entity as fibromyalgia.” As a clinical virologist, I strongly disagree with this as the distribution and number of tender points in fibromyalgia are different from those in the chronic fatigue syndrome, and the management of the two conditions is different.4 Patients with the syndrome should be advised not to increase their activities gradually until they feel 80% of normal,5 whereas patients with fibromyalgia may benefit from a regimen of increasing activity.4

You can read the rest of this comment here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2541601/pdf/bmj00468-0067b.pdf

 

Source: Ho-Yen DO. BMJ. Chronic fatigue syndrome and fibromyalgia. 1994 Dec 3;309(6967):1515. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2541601/

 

The etiology and possible treatment of chronic fatigue syndrome/fibromyalgia

Abstract:

It is suggested that chronic fatigue syndrome/fibromyalgia is caused by virus injury to the calcium channels leading to larger quantities than usual of calcium ions entering the striated muscle cells. Should this be true, then treatment with a calcium antagonist (CA) may possibly be of value.

 

Source: Lund-Olesen LH, Lund-Olesen K. The etiology and possible treatment of chronic fatigue syndrome/fibromyalgia. Med Hypotheses. 1994 Jul;43(1):55-8. http://www.ncbi.nlm.nih.gov/pubmed/7968720

 

Fibromyalgia, chronic fatigue syndrome, and myofascial pain syndrome

Abstract:

No major pathophysiologic or therapeutic findings have appeared over the past year regarding fibromyalgia, chronic fatigue syndrome, and myofascial pain syndrome, three poorly understood, controversial, and overlapping syndromes. The frequent prevalence of these disorders in association with Lyme disease and other medical and psychiatric illness was emphasized. New studies demonstrated the potential role for central nervous system activation in fibromyalgia and chronic fatigue syndrome.

 

Source: Goldenberg DL. Fibromyalgia, chronic fatigue syndrome, and myofascial pain syndrome. Curr Opin Rheumatol. 1994 Mar;6(2):223-33. http://www.ncbi.nlm.nih.gov/pubmed/8024971