Study Of Chronic Fatigue Syndrome Research Articles

Discernment of mediator and outcome measurement in the PACE trial

ObjectiveWhen measuring latent traits, such as those used in psychology and psychiatry, it can be unclear whether the instruments used are measuring different concepts. This issue is particularly important in the context of mediation analysis, since for a sound mediation hypothesis the mediator and outcome should be distinct. We sought to assess the extent of measurement overlap between cognitive and behavioural mediators and physical functioning and fatigue outcomes in a large trial of treatments for chronic fatigue syndrome. MethodsA secondary analysis of 640 participants in the “Pacing, graded Activity, and Cognitive behaviour therapy” trial was conducted. Potential measurement overlap was assessed using generalised linear latent variable models where confirmatory factor models quantified the extent to which the addition of cross-loading items significantly improved model fit. ResultsWe considered 13 mediators and two outcomes, giving a total of 26 mediator-outcome pairs. Of these, only six showed evidence of cross-loading items, supporting the suggestion that the chosen mediator and outcome constructs were conceptually distinct. ConclusionThis study highlights how established psychometric methods can be applied to assess measurement overlap in mediation analyses. We found minimal overlap between cognitive and behavioural mediators and physical functioning and fatigue outcomes that are often used in studies of chronic fatigue syndrome. The use of such methods in mediational studies where questionnaires are used to quantify latent traits would add to their robustness and transparency.

Are there subgroups of chronic fatigue syndrome? An exploratory cluster analysis of biological markers

BackgroundChronic fatigue syndrome (CFS) is defined according to subjective symptoms only, and several conflicting case definition exist. Previous research has discovered certain biological alterations. The aim of the present study was to explore possible subgroups based on biological markers within a widely defined cohort of adolescent CFS patients and investigate to what extent eventual subgroups are associated with other variables.MethodsThe Norwegian Study of Chronic Fatigue Syndrome in Adolescents: Pathophysiology and Intervention Trial (NorCAPITAL) has previously performed detailed investigation of immunological, autonomic, neuroendocrine, cognitive and sensory processing functions in an adolescent group of CFS patients recruited according to wide diagnostic criteria. In the present study, hierarchical cluster analyses (Ward’s method) were performed using representative variables from all these domains. Associations between clusters and constitutional factors (including candidate genetic markers), diagnostic criteria, subjective symptoms and prognosis were explored by standard statistical methods.ResultsA total of 116 patients (26.7% males, mean age 15.4 years) were included. The final cluster analyses revealed six clusters labelled pain tolerant & good cognitions, restored HPA dynamics, orthostatic intolerance, low-grade inflammation, pain intolerant & poor cognitions, and high vagal (parasympathetic) activity, respectively. There was substantial overlap between clusters. The pain intolerant & poor cognitions-cluster was associated with low functional abilities and quality of life, and adherence to the Canada 2003 diagnostic criteria for CFS. No other statistically significant cluster associations were discovered.ConclusionWithin a widely defined cohort of adolescent CFS patients, clusters could be delineated, but no distinct subgroups could be identified. Associations between clusters and constitutional factors, subjective symptoms and prognosis were scarce. These results question the clinical usefulness of searching for CFS subgroups, as well as the validity of the most “narrow” CFS diagnostic criteria.Trial registration: Clinical Trials NCT01040429

A systematic review of the association between fatigue and cognition in chronic noncommunicable diseases.

Fatigue is one of the most common symptoms associated with chronic noncommunicable diseases, and it may also increase cognitive impairment. However, associations between fatigue and cognitive impairment in chronic illnesses remain unclear. Therefore, the purpose of this systematic review was to examine research that investigated associations between level of fatigue and cognitive status. PubMed/Medline, PsycINFO, CINAHL, and Cochrane Database were searched for articles published between 2012 and 2018 using search terms fatigue, cognition, and various iterations of these terms. Study quality was assessed by the Joanna Briggs Institute Critical Appraisal Checklist tool. Of 1799 citations, 10 studies in samples of individuals with cancer, multiple sclerosis, neurosarcoidosis, and chronic fatigue syndrome met the inclusion criteria. Fatigue was found to be significantly correlated with cognitive impairment in one cancer-related study (r = -.480, p < .001), one multiple sclerosis study (β= -0.52, p < .0001), and two chronic fatigue syndrome studies (r = 0.397, p < .001; r = 0.388, p < .001). There is insufficient evidence examining the relationship between fatigue and cognitive impairment in patients with chronic illnesses. As a result, more studies are needed that examine potential relationships between these two symptoms in order to develop effective treatments for individuals living with a chronic noncommunicable disease.

Genetic variation in catechol-O-methyltransferase modifies effects of clonidine treatment in chronic fatigue syndrome.

Clonidine, an α2-adrenergic receptor agonist, decreases circulating norepinephrine and epinephrine, attenuating sympathetic activity. Although catechol-O-methyltransferase (COMT) metabolizes catecholamines, main effectors of sympathetic function, COMT genetic variation effects on clonidine treatment are unknown. Chronic fatigue syndrome (CFS) is hypothesized to result in part from dysregulated sympathetic function. A candidate gene analysis of COMT rs4680 effects on clinical outcomes in the Norwegian Study of Chronic Fatigue Syndrome in Adolescents: Pathophysiology and Intervention Trial (NorCAPITAL), a randomized double-blinded clonidine versus placebo trial, was conducted (N=104). Patients homozygous for rs4680 high-activity allele randomized to clonidine took 2,500 fewer steps compared to placebo (pinteraction=0.04). There were no differences between clonidine and placebo amongst patients with COMT low-activity alleles. Similar gene-drug interactions were observed for sleep (pint=0.003) and quality of life (pint=0.018). Detrimental effects of clonidine in the subset of CFS patients homozygous for COMT high-activity allele warrant investigation of potential clonidine-COMT interaction effects in other conditions.

Effects of low-dose clonidine on cardiovascular and autonomic variables in adolescents with chronic fatigue: a randomized controlled trial.

BackgroundChronic Fatigue Syndrome (CFS) is a common and disabling condition in adolescence with few treatment options. A central feature of CFS is orthostatic intolerance and abnormal autonomic cardiovascular control characterized by sympathetic predominance. We hypothesized that symptoms as well as the underlying pathophysiology might improve by treatment with the alpha2A–adrenoceptor agonist clonidine.MethodsA total of 176 adolescent CFS patients (12–18 years) were assessed for eligibility at a single referral center recruiting nation-wide. Patients were randomized 1:1 by a computer system and started treatment with clonidine capsules (25 μg or 50 μg twice daily, respectively, for body weight below/above 35 kg) or placebo capsules for 9 weeks. Double-blinding was provided. Data were collected from March 2010 until October 2012 as part of The Norwegian Study of Chronic Fatigue Syndrome in Adolescents: Pathophysiology and Intervention Trial (NorCAPITAL). Effect of clonidine intervention was assessed by general linear models in intention-to-treat analyses, including baseline values as covariates in the model.ResultsA total of 120 patients (clonidine group n = 60, placebo group n = 60) were enrolled and started treatment. There were 14 drop-outs (5 in the clonidine group, 9 in the placebo group) during the intervention period. At 8 weeks, the clonidine group had lower plasma norepinephrine (difference = 205 pmol/L, p = 0.05) and urine norepinephrine/creatinine ratio (difference = 3.9 nmol/mmol, p = 0.002). During supine rest, the clonidine group had higher heart rate variability in the low-frequency range (LF-HRV, absolute units) (ratio = 1.4, p = 0.007) as well as higher standard deviation of all RR-intervals (SDNN) (difference = 12.0 ms, p = 0.05); during 20° head-up tilt there were no statistical differences in any cardiovascular variable. Symptoms of orthostatic intolerance did not change during the intervention period.ConclusionsLow-dose clonidine reduces catecholamine levels in adolescent CFS, but the effects on autonomic cardiovascular control are sparse. Clonidine does not improve symptoms of orthostatic intolerance.Trial registrationClinical Trials ID: NCT01040429, date of registration 12/28/2009.

Pain and pressure pain thresholds in adolescents with chronic fatigue syndrome and healthy controls: a cross-sectional study

ObjectivesAlthough pain is a significant symptom in chronic fatigue syndrome (CFS), pain is poorly understood in adolescents with CFS. The aim of this study was to explore pain distribution and...

Modeling Bivariate Longitudinal Hormone Profiles by Hierarchical State Space Models

The hypothalamic-pituitary-adrenal (HPA) axis is crucial in coping with stress and maintaining homeostasis. Hormones produced by the HPA axis exhibit both complex univariate longitudinal profiles and complex relationships among different hormones. Consequently, modeling these multivariate longitudinal hormone profiles is a challenging task. In this article, we propose a bivariate hierarchical state space model, in which each hormone profile is modeled by a hierarchical state space model, with both population-average and subject-specific components. The bivariate model is constructed by concatenating the univariate models based on the hypothesized relationship. Because of the flexible framework of state space form, the resultant models not only can handle complex individual profiles, but also can incorporate complex relationships between two hormones, including both concurrent and feedback relationship. Estimation and inference are based on marginal likelihood and posterior means and variances. Computationally efficient Kalman filtering and smoothing algorithms are used for implementation. Application of the proposed method to a study of chronic fatigue syndrome and fibromyalgia reveals that the relationships between adrenocorticotropic hormone and cortisol in the patient group are weaker than in healthy controls. Supplementary materials for this article are available online.

A brain MRI study of chronic fatigue syndrome: evidence of brainstem dysfunction and altered homeostasis

To explore brain involvement in chronic fatigue syndrome (CFS), the statistical parametric mapping of brain MR images has been extended to voxel-based regressions against clinical scores. Using SPM5 we performed voxel-based morphometry (VBM) and analysed T1- and T2-weighted spin-echo MR signal levels in 25 CFS subjects and 25 normal controls (NC). Clinical scores included CFS fatigue duration, a score based on the 10 most common CFS symptoms, the Bell score, the hospital anxiety and depression scale (HADS) anxiety and depression, and hemodynamic parameters from 24-h blood pressure monitoring. We also performed group × hemodynamic score interaction regressions to detect locations where MR regressions were opposite for CFS and NC, thereby indicating abnormality in the CFS group. In the midbrain, white matter volume was observed to decrease with increasing fatigue duration. For T1-weighted MR and white matter volume, group × hemodynamic score interactions were detected in the brainstem [strongest in midbrain grey matter (GM)], deep prefrontal white matter (WM), the caudal basal pons and hypothalamus. A strong correlation in CFS between brainstem GM volume and pulse pressure suggested impaired cerebrovascular autoregulation. It can be argued that at least some of these changes could arise from astrocyte dysfunction. These results are consistent with an insult to the midbrain at fatigue onset that affects multiple feedback control loops to suppress cerebral motor and cognitive activity and disrupt local CNS homeostasis, including resetting of some elements of the autonomic nervous system (ANS). © 2011 The Authors. NMR in Biomedicine published by John Wiley & Sons, Ltd.

Reduced heart rate variability predicts poor sleep quality in a case–control study of chronic fatigue syndrome

Parasympathetic function is important in the induction and maintenance of sleep. We examined whether nocturnal vagal modulation of heart rate is related to the poor sleep quality commonly reported in chronic fatigue syndrome (CFS). Heart rate (HR, as R-R intervals) was continuously monitored during sleep in 20 patients with CFS and 20 matched control subjects. Questionnaires assessed demographic information, symptoms, functional impairment, and subjective sleep quality. CFS was associated with more sleep problems in general and poorer subjective sleep quality on the study night (all p < 0.003), and reports of repeated awakening during the night were 7 times more likely compared to healthy subjects (p = 0.017). Time and frequency-domain parameters of HR variability during sleep were significantly lower in patients with CFS (all p < 0.006). Multiple regression analyses revealed that heart rate variability (HRV) parameters were the best predictors of subjective sleep measures. This study identified significant reductions in vagal modulation of heart rate during sleep in CFS. Low HRV strongly predicted sleep quality-suggesting a pervasive state of nocturnal sympathetic hypervigilance in CFS.

Perspectives on Fatigue from the Study of Chronic Fatigue Syndrome and Related Conditions

Abstract Fatigue is a symptom whose causes are protean and whose phenotype includes physical, mood, and behavioral components. Chronic fatigue syndrome (CFS) is an illness that has strong biological underpinnings and no definite etiology. Diagnostic criteria established by the Centers for Disease Control and Prevention have helped classify CFS as an overlap of mood, behavioral, and biological components. These include the presence of fatigue for more than 6 months associated with a diminution of functional activity and somatic symptoms, and pain not attributable to a specific diagnosis or disease. Four of the following criteria need to be present: sore throat, impaired memory or cognition, unrefreshing sleep, postexertional fatigue, tender glands, aching stiff muscles, joint pain, and headaches. Many researchers have observed that CFS shares features in common with other somatic syndromes, including irritable bowel syndrome, fibromyalgia, and temporomandibular joint dysfunction. Correlations between inflammation and infection, augmented sensory processing, abnormalities of neurotransmitters, nerve growth factors, low levels of serotonin and norepinephrine, abnormalities of homeostasis of the stress system, and autonomic dysfunction may be hallmarks of CFS. The relative contributions of each of these abnormalities to the profound fatigue associated with CFS need to be explored further to better evaluate and treat the syndrome.

Validity of Self-Reported Body Mass Index and Sleeping Problems Among Adult Population of Georgia

Purpose: This study assessed the validity of body mass index (BMI) derived from self-reported height and weight in comparison to BMI derived from clinical measurement. We further examined the misclassification effect of self-reported BMI in association with complaints of snoring and excessive daytime sleepiness. Methods: Data came from a population-based study of chronic fatigue syndrome (CFS) and unwellness, between September 2004 and July 2005, in metropolitan, urban, and rural Georgia. We compared self-reported with clinically- measured height and weight from 774 persons aged 18-59 and the bias impact on their association with snoring and excessive daytime sleepiness. Results: The correlation coefficient between self-reported and clinically-measured BMI was 0.92 (p =25 kg/m 2 ), self-reported BMI had 89% sensitivity and 95% specificity compared to clinically-measured BMI. Misclassification of self-reported BMI categories revealed slightly higher odds ratios (ORs) for obese categories in predicting the likelihood of having a snoring problem than those based on measured values. Conclusions: Self-reported height and weight are valid for determining BMI categories and the relationship to snoring in a large-scale population study.

A two‐year follow‐up study of chronic fatigue syndrome comorbid with psychiatric disorders

Chronic fatigue syndrome patients often have comorbid psychiatric disorders such as major depressive disorders and anxiety disorders. However, the outcomes of chronic fatigue syndrome and the comorbid psychiatric disorders and the interactions between them are unknown. Therefore, a two-year prospective follow-up study was carried out on chronic fatigue syndrome patients with comorbid psychiatric disorders. A total of 155 patients who met the Japanese case definition of chronic fatigue syndrome were enrolled in this study. Comorbid psychiatric disorders were diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders 4th edition criteria. Patients with comorbid psychiatric disorders received psychiatric treatment in addition to medical therapy for chronic fatigue syndrome. Seventy patients participated in a follow-up interview approximately 24 months later. Of the 70 patients with chronic fatigue syndrome, 33 patients were diagnosed as having comorbid psychiatric disorders including 18 major depressive disorders. Sixteen patients with psychiatric disorders and eight patients with major depressive disorders did not fulfill the criteria of any psychiatric disorders at the follow up. As for chronic fatigue syndrome, nine out of the 70 patients had recovered at the follow up. There is no significant influence of comorbid psychiatric disorders on the outcome of chronic fatigue syndrome. Chronic fatigue syndrome patients have a relatively high prevalence of comorbid psychiatric disorders, especially major depressive disorders. The outcomes of chronic fatigue syndrome and psychiatric disorders are independent. Therefore treatment of comorbid psychiatric disorders is necessary in addition to the medical treatment given for chronic fatigue syndrome.

An angiotensin-1 converting enzyme polymorphism is associated with allostatic load mediated by C-reactive protein, interleukin-6 and cortisol

Allostatic load (AL) is a theoretical framework that describes the cumulative physiologic effects of adaptation to change or stress throughout the lifespan. AL is operationalized by a composite index of multiple biomarkers. Accordingly, genes, behavior and environment contribute to AL. To determine if individual differences in AL may be influenced by inherent genetic variation, we calculated an allostatic load index (ALI) for 182 Caucasian subjects derived from a population-based study of chronic fatigue syndrome. Nearly 65% of the subjects in this study sample reported fatiguing illness. ALI was calculated based on 11 measures representing metabolic, cardiovascular, inflammatory, hypothalamic-pituitary-adrenal (HPA) axis and sympathetic nervous system (SNS) activities. Subjects were dichotomized into high (ALI > or = 3) or low (ALI < 3) AL groups, and the association between high AL and 129 polymorphisms in 32 genes related to the HPA axis, neurotransmission, inflammation, cardiovascular and metabolic functions were evaluated. Polymorphisms in angiotensin-1 converting enzyme (ACE), corticotropin-releasing hormone receptor 1 (CRHR1), and serotonin receptors (HTR3A and HTR4) were associated with AL (p=0.0007-0.0486), but only one polymorphism, rs4968591, in ACE remained significant after correction for multiple comparisons. The T allele of ACE rs4968591 was more common in subjects with high AL (67.5%) than in subjects with low AL (49.3%) (p=0.0007), and this effect appeared independent of age, sex, body mass index and fatigue status. Additionally, high interleukin-6 (IL-6; p(trend)=0.04), and C-reactive protein (CRP; p(trend)=0.01) levels, as well as low urinary cortisol levels in females (p=0.03) were associated with the T allele, which may result in allele-specific binding of the transcription factor, E2F1. Our results suggest a role for ACE in the bidirectional communication between the central nervous and immune systems in response to stress. Further studies will be needed (a) to replicate the association between AL and ACE polymorphisms in population studies designed to differentiate the effects of sex, age and racial/ethnic background, (b) to evaluate the effect of allele-specific binding of E2F1 at rs4968591, and (c) to examine the role of ACE in the co-regulation of CRP, IL-6 and cortisol.

Neurocognitive and functional outcomes in persons recovering from West Nile virus illness

Long-term neurocognitive and functional impairments following West Nile virus (WNV) disease are poorly understood. We assessed quality-of-life indices and neurocognitive performance in a cohort of 54 persons recovering from one of three WNV disease syndromes (fever [WNF], meningitis [WNM], or encephalitis [WNE]) approximately 1.5 years following acute illness. We compared findings between the three syndromic groups; the study cohort and a demographically similar group of 55 controls from a study of chronic fatigue syndrome (CFS); and the study cohort and a 'normative' control population based on cognitive test data. Persistent symptoms, diminished quality of life, and functional impairment were reported by 50% of WNF patients, and 75% each of WNM and WNE patients. Overall, objective neurocognitive performance did not differ significantly between the three syndromic groups, or between the study cohort and the CFS controls or the normative controls. In some neurocognitive subtests, the study cohort scored below the 15th percentile when compared with normative control data. Most persons who returned to independent living following hospitalization for WNV illness had persistent subjective complaints, but had normal cognitive function. However, a minority displayed subtle neurocognitive deficits more than 18 months following acute disease.

Cognitive Function and Major Depression in Chronic Fatigue: The Apathy Construct

ABSTRACTObjective: The current study examined cognitive function, major depressive disorder (MDD), and apathy construct symptoms in a large multi-site surveillance study of chronic fatigue syndrome conducted by the Centers for Disease Control and Prevention. Method: Subjects underwent neuropsychological testing and were administered the Diagnostic Interview Schedule to establish psychiatric diagnoses. Questions in the Beck Depression Inventory relating to motivation were used to develop an apathy construct. Results: Neuropsychological test results showed impairment in multiple cognitive domains in over 25% of the cohort, and raised proportions of outliers in motor and executive function. Memory complaints were not associated with tests of memory function. The apathy construct rather than MDD was associated with impaired cognition. Conclusions: Impaired cognition in chronic fatigue does not appear to be associated with MDD but rather with endorsement of construct symptoms. Similar associations were reporte...

The Challenge of Integrating Disparate High-Content Data: Epidemiological, Clinical and Laboratory Data Collected during an in-Hospital Study of Chronic Fatigue Syndrome

Chronic fatigue syndrome (CFS) is a debilitating illness characterized by multiple unexplained symptoms including fatigue, cognitive impairment and pain. People with CFS have no characteristic physical signs or diagnostic laboratory abnormalities, and the etiology and pathophysiology remain unknown. CFS represents a complex illness that includes alterations in homeostatic systems, involves multiple body systems and results from the combined action of many genes, environmental factors and risk-conferring behavior. In order to achieve understanding of complex illnesses, such as CFS, studies must collect relevant epidemiological, clinical and laboratory data and then integrate, analyze and interpret the information so as to obtain meaningful clinical and biological insight. This issue of Pharmacogenomics represents such an approach to CFS. Data was collected during a 2-day in-hospital study of persons with CFS, other medically and psychiatrically unexplained fatiguing illnesses and nonfatigued controls identified from the general population of Wichita, KS, USA. While in the hospital, the participants' psychiatric status, sleep characteristics and cognitive functioning was evaluated, and biological samples were collected to measure neuroendocrine status, autonomic nervous system function, systemic cytokines and peripheral blood gene expression. The data generated from these assessments was made available to a multidisciplinary group of 20 investigators from around the world who were challenged with revealing new insight and algorithms for integration of this complex, high-content data and, if possible, identifying molecular markers and elucidating pathophysiology of chronic fatigue. The group was divided into four teams with representation from the disciplines of medicine, mathematics, biology, engineering and computer science. The papers in this issue are the culmination of this 6-month challenge, and demonstrate that data integration and multidisciplinary collaboration can indeed yield novel approaches for handling large, complex datasets, and reveal new insight and relevance to a complex illness such as CFS.

A Follow-up Study of Chronic Fatigue Syndrome in Children and Adolescents: Symptom Persistence and School Absenteeism

This is a follow-up study of 28 young people aged between 7 and 17 meeting the Oxford criteria for the diagnosis of chronic fatigue syndrome treated in a specialist paediatric/psychiatric service. Retrospective case note analysis revealed a wide range and duration of symptoms together with high levels of school absenteeism prior to the diagnosis. The mean follow-up interval after discharge from the specialist service was 3 years and although most of the young people regarded themselves as fully recovered by this time, improvement was variable and about one third were still experiencing disabling symptoms. The illness had impacted on the education or career plans of all the young people to some extent with 15 experiencing difficulty returning to school. This article highlights the need for early recognition and diagnosis of chronic fatigue syndrome in young people and the importance of continuing paediatric support to reduce symptom persistence in the sensitive recovery period. Maintaining school attendance by close liaison between health and education services both before and after diagnosis and treatment is also vital if long-term morbidity is to be reduced.

Causal Attributions, Perceived Control, and Psychological Adjustment: A Study of Chronic Fatigue Syndrome1

Causal attributions control, beliefs, and helpful and unhelpful support attempts were examined among people experiencing chronic fatigue syndrome (CFS) and their close others. Results revealed that 84% of respondents with CFS believed that their illness was due, at least in part, to physical or external causes, whereas 47% mentioned internal/psychological causes. Reports of internal causal attributions for CFS were positively correlated with indicators of poor psychological adjustment among those with CFS. Having an external locus of control (i.e., to powerful others) was also associated with poorer psychological adjustment among respondents with CFS. Close others' causal attributions to internal factors were related to frequency of self‐reported unhelpful support attempts and to reports of depression and anxiety those respondents with CFS.

Orthostatic instability in a population-based study of chronic fatigue syndrome

Purpose Autonomic nervous system dysfunction has been suggested as involved in the pathophysiology of chronic fatigue syndrome. This population-based case control study addressed the potential association between orthostatic instability (one sign of dysautonomia) and chronic fatigue syndrome. Subjects and methods Fifty-eight subjects who fulfilled criteria of the 1994 chronic fatigue syndrome research case definition and 55 healthy controls participated in a 2-day inpatient evaluation. Subjects had been identified during a 4-year population-based chronic fatigue syndrome surveillance study in Wichita, Kan. The present study evaluated subjects’ current medical and psychiatric status, reviewed past medical/psychiatric history and medication use, used a stand-up test to screen for orthostatic instability, and conducted a head-up tilt table test to diagnose orthostatic instability. Results No one manifested orthostatic instability in the stand-up test. The head-up tilt test elicited orthostatic instability in 30% of eligible chronic fatigue syndrome subjects (all with postural orthostatic tachycardia) and 48% of controls (50% with neurally mediated hypotension); intolerance was present in only nonfatigued (n = 7) subjects. Neither fatigue nor illness severity were associated with outcome. Conclusions Orthostatic instability was similar in persons with chronic fatigue syndrome and nonfatigued controls subjects recruited from the general Wichita population. Delayed responses to head-up tilt tests were common and may reflect hydration status. These findings suggest reappraisal of primary dysautonomia as a factor in the pathogenesis of chronic fatigue syndrome.

A preliminary epidemiological study and discussion on traditional Chinese medicine pathogenesis of chronic fatigue syndrome in Hong Kong

Our purpose is to conduct an epidemiological study of chronic fatigue syndrome (CFS) and its syndrome types and symptoms of traditional Chinese medicine (TCM) among adults (20-50 years old) in Hong Kong, and to discuss the TCM pathogenesis. Cross-sectional questionnaire survey. Demographic data, CDC (1994) CFS diagnostic criteria, Trudie Chalder fatigue scale, and China national standard for TCM syndrome types criteria. Twenty to fifty years old adults by convenient sampling. One thousand and thirteen subjects were successfully interviewed. Five hundred and eighty-five subjects (57.8%) had different levels of fatigue. Sixty-five subjects (6.4%) met CFS diagnostic criteria. In terms of TCM syndrome types, blood stasis due to qi deficiency had the highest prevalence (35.7%) among CFS. In the 54 symptoms investigated in total, the first eight symptoms in order of appearing rates were soreness of loins and weakness in knees, poor spirit, lassitude, pain, insomnia, forgetting, vessels blood stasis, vertigo and dazzle. The mostly appeared tongue figures were pale and corpulent or pale dim tongue proper, white and white greasy tongue coating, and the mostly appeared pulse figure was sunken-thin. The point prevalence of CFS among adults of 20 to 50 years old was found to be 6.4%. The most prevalent TCM syndrome type was blood stasis due to qi deficiency. The TCM pathogenesis of CFS was deficiency of origin, mainly deficiency of qi and kidney, with excess of superficiality.