Clinical characteristics of patients with chronic fatigue syndrome: analysis of 82 cases

Abstract:

OBJECTIVE: To analyze the clinical characteristics of Chinese patients suffering from chronic fatigue syndrome (CFS) and provide clinical and laboratory evidence for the study of its etiology and treatment.

METHODS: 82 patients with CFS diagnosed based on the CDC criteria 1994 were recruited. History was collected, and physical examination was made. SCL-90 and memory test were used, and Hamilton Anxiety Rating Scale was used to those showing depression and/or anxiety. Laboratory examination, including examination of electrolytes, blood sugar, creatinine, bilirubin, alkaline phosphatase, alanine trasaminase, etc, was conducted. Western blotting was used to detect the protein-24 of Borna disease virus (BDV) in the plasma of 61 patients and 73 healthy controls. High-pressure chromatography was conducted to detect n-6 fatty acids on the membrane of erythrocytes of 42 patients and 37 healthy controls. Plasma L-carnitine in 61 patients and 73 healthy controls was detected by zymological analysis. In different examinations sex and age-matched controls were used.

RESULTS: Most of the patients were 21 approximately 50 years old (74/82, 90.24%). No gender difference was found. The patients usually had 4 approximately 6 symptoms besides distinctive fatigue. Descent of remembrance and/or attention was the most conspicuous accompanying symptoms (69/82, 84.15%). Abnormalities in SCL-90 scores were present in 57 patients (69.51%), e.g, somatization existed most commonly (32/82, 39.02%), and anxiety and depression were 20.73% (17/82) and 18.29% (15/82) respectively. The prevalence of anti-BDV-p24 antibody was 20.73% (17/82), significantly higher than that of the controls (0%, chi(2) = 6.673, P = 0.010). The arachidonic acid level was significantly lower in the CFS group than in the controls (P > 0.05) and there were no differences in linoleic acid and ETA (both P > 0.05). The level of L-carnitine was 6.4336 +/- 3.4225, significantly lower than that of the control group (7.6666 +/- 3.5819, t = 2.025, P = 0.045) and the L-carnitine level was increased 2 weeks after supplementary treatment, together with improvement of symptoms.

CONCLUSION: Most of the CFS patients are young and middle-aged. Descent of reorganization is common in these patients. Psychological abnormalities exist in most patients. Some patients are infected with BDV, some with deficiency of nutrition and/or abnormality of energy metabolism.

 

Source: Li YJ, Wang DX, Bai XL, Chen J, Liu ZD, Feng ZJ, Zhao YM. Clinical characteristics of patients with chronic fatigue syndrome: analysis of 82 cases. Zhonghua Yi Xue Za Zhi. 2005 Mar 16;85(10):701-4. [Article in Chinese] http://www.ncbi.nlm.nih.gov/pubmed/15932738

 

Mechanisms underlying fatigue: a voxel-based morphometric study of chronic fatigue syndrome

Abstract:

BACKGROUND: Fatigue is a crucial sensation that triggers rest, yet its underlying neuronal mechanisms remain unclear. Intense long-term fatigue is a symptom of chronic fatigue syndrome, which is used as a model to study the mechanisms underlying fatigue.

METHODS: Using magnetic resonance imaging, we conducted voxel-based morphometry of 16 patients and 49 age-matched healthy control subjects.

RESULTS: We found that patients with chronic fatigue syndrome had reduced gray-matter volume in the bilateral prefrontal cortex. Within these areas, the volume reduction in the right prefrontal cortex paralleled the severity of the fatigue of the subjects.

CONCLUSION: These results are consistent with previous reports of an abnormal distribution of acetyl-L-carnitine uptake, which is one of the biochemical markers of chronic fatigue syndrome, in the prefrontal cortex. Thus, the prefrontal cortex might be an important element of the neural system that regulates sensations of fatigue.

 

Source: Okada T, Tanaka M, Kuratsune H, Watanabe Y, Sadato N. Mechanisms underlying fatigue: a voxel-based morphometric study of chronic fatigue syndrome. BMC Neurol. 2004 Oct 4;4(1):14. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC524491/

 

Exploratory open label, randomized study of acetyl- and propionylcarnitine in chronic fatigue syndrome

Abstract:

OBJECTIVES: We compared the effects of acetylcarnitine, propionylcarnitine and both compounds on the symptoms of chronic fatigue syndrome(CFS).

METHODS: In an open, randomized fashion we compared 2 g/d acetyl-L-carnitine, 2 g/d propionyl-L-carnitine, and its combination in 3 groups of 30 CFS patients during 24 weeks. Effects were rated by clinical global impression of change. Secondary endpoints were the Multidimensional Fatigue Inventory, McGill Pain Questionnaire, and the Stroop attention concentration test. Scores were assessed 8 weeks before treatment; at randomization; after 8, 16, and 24 weeks of treatment; and 2 weeks later.

RESULTS: Clinical global impression of change after treatment showed considerable improvement in 59% of the patients in the acetylcarnitine group and 63% in the propionylcarnitine group, but less in the acetylcarnitine plus propionylcarnitine group (37%). Acetylcarnitine significantly improved mental fatigue (p =.015) and propionylcarnitine improved general fatigue (p =.004). Attention concentration improved in all groups, whereas pain complaints did not decrease in any group. Two weeks after treatment, worsening of fatigue was experienced by 52%, 50%, and 37% in the acetylcarnitine, propionylcarnitine, and combined group, respectively. In the acetylcarnitine group, but not in the other groups, the changes in plasma carnitine levels correlated with clinical improvement.

CONCLUSIONS: Acetylcarnitine and propionylcarnitine showed beneficial effect on fatigue and attention concentration. Less improvement was found by the combined treatment. Acetylcarnitine had main effect on mental fatigue and propionylcarnitine on general fatigue.

 

Source: Vermeulen RC, Scholte HR. Exploratory open label, randomized study of acetyl- and propionylcarnitine in chronic fatigue syndrome. Psychosom Med. 2004 Mar-Apr;66(2):276-82. http://www.ncbi.nlm.nih.gov/pubmed/15039515

 

Brain regions involved in fatigue sensation: reduced acetylcarnitine uptake into the brain

Abstract:

Fatigue is an indispensable sense for ordering rest. However, the neuronal and molecular mechanisms of fatigue remain unclear. Chronic fatigue syndrome (CFS) with long-lasting fatigue sensation seems to be a good model for studying these mechanisms underlying fatigue sensation.

Recently, we found that most patients with CFS showed a low level of serum acetylcarnitine, which well correlated with the rating score of fatigue, and that a considerable amount of acetyl moiety of serum acetylcarnitine is taken up into the brain. Here we show by metabolite analysis of the mouse brain that an acetyl moiety taken up into the brain through acetylcarnitine is mainly utilized for the biosynthesis of glutamate.

When we studied the cerebral uptake of acetylcarnitine by using [2-(11)C]acetyl-L-carnitine in 8 patients with CFS and in 8 normal age- and sex-matched controls, a significant decrease was found in several regions of the brains of the patient group, namely, in the prefrontal (Brodmann’s area 9/46d) and temporal (BA21 and 41) cortices, anterior cingulate (BA24 and 33), and cerebellum.

These findings suggest that the levels of biosynthesis of neurotransmitters through acetylcarnitine might be reduced in some brain regions of chronic fatigue patients and that this abnormality might be one of the keys to unveiling the mechanisms of the chronic fatigue sensation.

 

Source: Kuratsune H, Yamaguti K, Lindh G, Evengård B, Hagberg G, Matsumura K, Iwase M, Onoe H, Takahashi M, Machii T, Kanakura Y, Kitani T, Långström B, Watanabe Y. Brain regions involved in fatigue sensation: reduced acetylcarnitine uptake into the brain. Neuroimage. 2002 Nov;17(3):1256-65. http://www.ncbi.nlm.nih.gov/pubmed/12414265

 

Normal carnitine levels in patients with chronic fatigue syndrome

Abstract:

BACKGROUND: Patients with chronic fatigue syndrome (CFS) complain of muscle pain and impaired exercise tolerance. Previous studies show that this is due to systemic carnitine deficiency. We investigated the hypothesis that carnitine deficiency plays an important role in CFS in female CFS patients and compared their results with neighbourhood controls.

METHODS: The level of total carnitine, free carnitine, acylcarnitine and carnitine esters were measured in 25 female CFS patients and 25 healthy matched neighbourhood controls in a blinded fashion.

RESULTS: The previously reported decreased level of acylcarnitine in CFS patients was not confirmed. There were also no significant differences in levels of total carnitine, free carnitine and 20 carnitine esters between CFS patients and controls.

CONCLUSIONS: The present study demonstrates that serum carnitine deficiency does not contribute to or causes the symptoms in many CFS patients.

 

Source: Soetekouw PM, Wevers RA, Vreken P, Elving LD, Janssen AJ, van der Veen Y, Bleijenberg G, van der Meer JW. Normal carnitine levels in patients with chronic fatigue syndrome. Neth J Med. 2000 Jul;57(1):20-4. http://www.ncbi.nlm.nih.gov/pubmed/10862998

 

Nutritional strategies for treating chronic fatigue syndrome

Abstract:

Despite considerable worldwide efforts, no single etiology has been identified to explain the development of chronic fatigue syndrome (CFS). It is likely that multiple factors promote its development, sometimes with the same factors both causing and being caused by the syndrome.

A detailed review of the literature suggests a number of marginal nutritional deficiencies may have etiologic relevance. These include deficiencies of various B vitamins, vitamin C, magnesium, sodium, zinc, L-tryptophan, L-carnitine, coenzyme Q10, and essential fatty acids. Any of these nutrients could be marginally deficient in CFS patients, a finding that appears to be primarily due to the illness process rather than to inadequate diets. It is likely that marginal deficiencies not only contribute to the clinical manifestations of the syndrome, but also are detrimental to the healing processes.

Therefore, when feasible, objective testing should identify them and their resolution should be assured by repeat testing following initiation of treatment. Moreover, because of the rarity of serious adverse reactions, the difficulty in ruling out marginal deficiencies, and because some of the therapeutic benefits of nutritional supplements appear to be due to pharmacologic effects, it seems rational to consider supplementing CFS patients with the nutrients discussed above, along with a general high-potency vitamin/mineral supplement, at least for a trial period.

Comment in: Nutritional strategies for treating chronic fatigue syndrome. [Altern Med Rev. 2001]

 

Source: Werbach MR. Nutritional strategies for treating chronic fatigue syndrome. Altern Med Rev. 2000 Apr;5(2):93-108. http://www.altmedrev.com/publications/5/2/93.pdf (Full article)

 

Amantadine and L-carnitine treatment of Chronic Fatigue Syndrome

Abstract:

Carnitine is essential for mitochondrial energy production. Disturbance in mitochondrial function may contribute to or cause the fatigue seen inChronic Fatigue Syndrome (CFS) patients.

Previous investigations have reported decreased carnitine levels in CFS. Orally administered L-carnitine is an effective medicine in treating the fatigue seen in a number of chronic neurologic diseases. Amantadine is one of the most effective medicines for treating the fatigue seen in multiple sclerosis patients. Isolated reports suggest that it may also be effective in treating CFS patients. Formal investigations of the use of L-carnitine and amantadine for treating CFS have not been previously reported.

We treated 30 CFS patients in a crossover design comparing L-carnitine and amantadine. Each medicine was given for 2 months, with a 2-week washout period between medicines. L-Carnitine or amantadine was alternately assigned as first medicine.

Amantadine was poorly tolerated by the CFS patients. Only 15 were able to complete 8 weeks of treatment, the others had to stop taking the medicine due to side effects. In those individuals who completed 8 weeks of treatment, there was no statistically significant difference in any of the clinical parameters that were followed.

However, with L-carnitine we found statistically significant clinical improvement in 12 of the 18 studied parameters after 8 weeks of treatment. None of the clinical parameters showed any deterioration. The greatest improvement took place between 4 and 8 weeks of L-carnitine treatment. Only 1 patient was unable to complete 8 weeks of treatment due to diarrhea.

L-Carnitine is a safe and very well tolerated medicine which improves the clinical status of CFS patients. In this study we also analyzed clinical and laboratory correlates of CFS symptomatology and improvement parameters.

 

Source: Plioplys AV, Plioplys S. Amantadine and L-carnitine treatment of Chronic Fatigue Syndrome. Neuropsychobiology. 1997;35(1):16-23. http://www.ncbi.nlm.nih.gov/pubmed/9018019

 

Abnormalities of carnitine metabolism in chronic fatigue syndrome

Abstract:

Carnitine may be involved in the pathogenesis of the chronic fatigue syndrome (CFS). However, no information about the cellular metabolism of carnitine in CFS patients is currently available. Therefore, we aimed to measure the levels of carnitine (total, free and short-chain) in both peripheral blood lymphocytes (PBLs) and sera from patients with CFS.

The serum levels of total, free and short-chain were comparable in CFS patients, considered as the whole group, to those in healthy control subjects, even though a trend indicating slightly reduced serum concentrations of free carnitine was observed in male patients with CFS. In contrast, the concentrations of total, free and short-chain carnitine in PBLs from patients with CFS were significantly lower than in cells from healthy controls.

Our study indicates that patients with CFS require exogenous carnitine supplementation. The low carnitine concentrations in PBLs from patients with CFS probably reflect the carnitine deficiency occurring in other tissues, including the skeletal muscles. The low cellular concentrations of carnitines may help to explain both the immunological abnormalities and the impaired energy metabolism in skeletal muscles.

 

Source: Majeed T, de Simone C, Famularo G, Marcellini S, Behan PO. Abnormalities of carnitine metabolism in chronic fatigue syndrome. Eur J Neurol. 1995 Nov;2(5):425-8. doi: 10.1111/j.1468-1331.1995.tb00151.x. http://www.ncbi.nlm.nih.gov/pubmed/24283722

 

Serum levels of carnitine in chronic fatigue syndrome: clinical correlates

Abstract:

Carnitine is essential for mitochondrial energy production. Disturbance in mitochondrial function may contribute to or cause the fatigue seen in chronic fatigue syndrome (CFS) patients. One previous investigation has reported decreased acylcarnitine levels in 38 CFS patients.

We investigated 35 CFS patients (27 females and 8 males); our results indicate that CFS patients have statistically significantly lower serum total carnitine, free carnitine and acylcarnitine levels, not only lower acylcarnitine levels as previously reported. We also found a statistically significant correlation between serum levels of total and free carnitine and clinical symptomatology. Higher serum carnitine levels correlated with better functional capacity.

These findings may be indicative of mitochondrial dysfunction, which may contribute to or cause symptoms of fatigue in CFS patients.

 

Source: Plioplys AV, Plioplys S. Serum levels of carnitine in chronic fatigue syndrome: clinical correlates. Neuropsychobiology. 1995;32(3):132-8. http://www.ncbi.nlm.nih.gov/pubmed/8544970

 

Chronic fatigue syndrome: studies on skeletal muscle

Abstract:

Chronic fatigue syndrome represents a poorly defined disease with protean clinical manifestations, the majority of them expressed as a muscle fatigue or as inability to maintain the expected muscle strength.

In the present work we studied muscle function and muscle histopathology in 20 patients fulfilling the proposed criteria for chronic fatigue syndrome. Special interest is directed towards the immunoreactive expression of class I MHC molecules comparing some inflammatory and virus-related myopathies with muscles from chronic fatigue syndrome.

Only minor morphological changes were detected in 9 out of 20 patients of the series. The nonspecific morphological changes in muscle tissue and the lack of class I MHC expression does not support the viral etiology of muscle fatigue in chronic fatigue syndrome. In contrast with the reported clinical improvement with high doses of essential fatty acids, our patients’ clinical condition did not improve after three months of L-carnitine therapy.

 

Source: Grau JM, Casademont J, Pedrol E, Fernández-Solà J, Cardellach F, Barros N, Urbano-Márquez A. Chronic fatigue syndrome: studies on skeletal muscle. Clin Neuropathol. 1992 Nov-Dec;11(6):329-32. http://www.ncbi.nlm.nih.gov/pubmed/1473316