Factor analysis of symptoms among subjects with unexplained chronic fatigue: what can we learn about chronic fatigue syndrome?

Abstract:

OBJECTIVE: Chronic fatigue syndrome (CFS) case definitions agree that fatigue must be unexplained, debilitating and present for at least 6 months, but they differ over accompanying symptoms. Our objective was to compare the 1994 CFS case-defining symptoms with those identified by factor analysis.

METHODS: We surveyed the Wichita population and measured the occurrence of 21 symptoms in 1391 chronically fatigued subjects who did not report fatigue-associated medical or psychiatric conditions. We used factor analyses to identify symptom dimensions of fatigue and cluster analysis to assign subjects to subgroups.

RESULTS: Forty-three subjects had CFS. We confirmed three factors: musculoskeletal, infection and cognition-mood-sleep, essentially defined by CFS symptoms. Although factor scores were higher among CFS subjects, CFS and non-CFS distributions overlapped substantially. Three clusters also showed overlap between CFS and non-CFS subjects.

CONCLUSION: CFS symptomatology is a multidimensional phenomenon overlapping with other unexplained fatiguing syndromes and this must be considered in CFS research.

 

Source: Nisenbaum R, Reyes M, Unger ER, Reeves WC. Factor analysis of symptoms among subjects with unexplained chronic fatigue: what can we learn about chronic fatigue syndrome? J Psychosom Res. 2004 Feb;56(2):171-8. http://www.ncbi.nlm.nih.gov/pubmed/15016574

 

Effect of Kuibitang on lipopolysaccharide-induced cytokine production in peripheral blood mononuclear cells of chronic fatigue syndrome patients

Abstract:

Kuibitang (KBT) is clinically used to treat patients suffering from chronic fatigue syndrome (CFS) in South Korea. However, its effect has not been investigated experimentally. Recent reports have shown that CFS patients display an altered cytokine production. We examined the effect of KBT on lipopolysaccharide (LPS)-induced various cytokines production in peripheral blood mononuclear cells (PBMC) of CFS patients and healthy controls. KBT (1 mg/ml) significantly inhibited LPS-induced tumor necrosis factor-alpha, interleukin-10, and transforming growth factor-beta1 production in PBMC of CFS patients. However, LPS-induced interferon-gamma production was significantly increased by KBT (0.01 mg/ml). These results provide evidence of a novel activity of the KBT that regulate cytokines production related with CFS.

 

Source: Shin HY, An NH, Cha YJ, Shin EJ, Shin TY, Baek SH, Kim CH, Lyu YS, Lee EJ, Kim HM. Effect of Kuibitang on lipopolysaccharide-induced cytokine production in peripheral blood mononuclear cells of chronic fatigue syndrome patients. J Ethnopharmacol. 2004 Feb;90(2-3):253-9. http://www.ncbi.nlm.nih.gov/pubmed/15013189

 

Neuropsychological deficits in patients with chronic fatigue syndrome

Abstract:

The degree of neuropsychological dysfunction across multiple domains was examined in individuals suffering from chronic fatigue syndrome(CFS). In this descriptive study, a similar series of neuropsychological tests was administered to a group of CFS patients and healthy participants. More specifically, CFS patients (n = 141) who met the 1994 Case Definition criteria were compared to 76 healthy control participants on tests of memory, attention (concentration), speed of information processing, motor speed, and executive functioning.

On the 18 measures administered, CFS patients scored 1 standard deviation below the healthy mean on nine measures and scored 2 standard deviations below the healthy mean on four of the measures. Moreover, results indicated that CFS patients were more likely than healthy controls to fail (1.6 SD below the healthy mean) at least one test in each of the following domains: attention, speed of information processing, and motor speed, but not on measures of memory and executive functioning. Finally, CFS patients demonstrated a greater total number of tests failed across domains.

 

Source: Busichio K, Tiersky LA, Deluca J, Natelson BH. Neuropsychological deficits in patients with chronic fatigue syndrome. J Int Neuropsychol Soc. 2004 Mar;10(2):278-85. http://www.ncbi.nlm.nih.gov/pubmed/15012848

 

Chronic fatigue syndrome in adolescents: a follow-up study

Abstract:

OBJECTIVES: To compare the frequency of persistent symptoms up to 8 years after illness onset in adolescents diagnosed as having chronic fatigue syndrome, idiopathic chronic fatigue, and unexplained fatigue for less than 6 months, and to determine if hospital admission is associated with outcome.

DESIGN: A cohort study using questionnaire follow-up.

SETTING: A tertiary referral hospital.

PATIENTS: Consecutive adolescents referred for assessment of persistent fatigue were identified and retrospectively divided into 3 groups according to the diagnostic criteria for chronic fatigue syndrome and idiopathic chronic fatigue.

INTERVENTION: A questionnaire was designed and administered by telephone at a mean of 4.57 years after the initial examination.

MAIN OUTCOME MEASURE: The persistence of self-reported symptoms was compared with respect to patient group and admission.

RESULTS: Outcome data were obtained for 34 (69%) of the 49 eligible subjects. Twenty-five percent of the chronic fatigue syndrome group showed near to complete improvement, 31% showed partial improvement, and 44% showed no improvement. The idiopathic chronic fatigue group had near to complete recovery in 50%, partial in 10%, and no improvement in 40%. Those with unexplained fatigue for less than 6 months had all recovered. There was no difference between the outcome of the subjects admitted to the hospital and those managed as outpatients.

CONCLUSIONS: Adolescents with less than 6 months of fatigue have a good outcome. Unexplained fatigue lasting more than 6 months has a similar outcome regardless of the presence of minor criteria for chronic fatigue syndrome.

Comment in: Adolescent chronic fatigue syndrome. [Arch Pediatr Adolesc Med. 2004]

 

Source: Gill AC, Dosen A, Ziegler JB. Chronic fatigue syndrome in adolescents: a follow-up study. Arch Pediatr Adolesc Med. 2004 Mar;158(3):225-9. http://www.ncbi.nlm.nih.gov/pubmed/14993080

 

Efficacy of cognitive-behavioural therapy by general practitioners for unexplained fatigue among employees: Randomised controlled trial

Abstract:

BACKGROUND: Fatigue is a common complaint that may lead to long-term sick leave and work disability.

AIMS: To assess the efficacy of cognitive-behavioural therapy by general practitioners for unexplained, persistent fatigue among employees.

METHOD: A randomised controlled trial, using a pre-randomisation design in primary care, investigated 151 employees on sick leave with fatigue. Participants in the experimental group were offered five to seven 30 min sessions of cognitive-behavioural therapy by a general practitioner; those in the control group were offered no treatment. Main outcome measures (fatigue severity, self-reported absenteeism, registered absenteeism and clinical recovery) were assessed at 4 months, 8 months and 12 months.

RESULTS: At baseline, 44% of the patients already met research criteria for chronic fatigue syndrome. There was no significant difference between the experimental group and the control group on primary or secondary outcomes at any point.

CONCLUSIONS: Cognitive-behavioural therapy by general practitioners for unexplained, persistent fatigue did not prove to be an effective intervention. Since these doctors were unable to deliver this therapy effectively under ideal circumstances, it is unlikely that doctors in routine practice would be more successful in doing so.

 

Source: Huibers MJ, Beurskens AJ, Van Schayck CP, Bazelmans E, Metsemakers JF, Knottnerus JA, Bleijenberg G. Efficacy of cognitive-behavioural therapy by general practitioners for unexplained fatigue among employees: Randomised controlled trial. Br J Psychiatry. 2004 Mar;184:240-6. http://bjp.rcpsych.org/content/184/3/240.long (Full article)

 

Chronic fatigue syndrome in a cognitive perspective. A therapeutic model

Abstract:

The cognitive approach to the treatment of chronic fatigue syndrome (CSF) is based on a multifactor etiological hypothesis, i.e. inaccurate beliefs and attitudes to the illness interact with pathophysiological processes, ineffective coping behaviours, negative states of mood, social problem, to perpetuate the illness. Patients suffering from CFS are supposed to be hypervigilant to somatic sensations and to interpret them as signs of impending physical catastrophe.

The aim of the this paper is to describe the clinical implementation of principles of cognitive therapy in the treatment of CFS. Basic to the treatment approach is a collaborative, listening and empathic attitude, sensitive to the patient’s personal beliefs and potential threats to self-esteem. The aim is to develop more useful, functional, formulations of the illness. The patient and the therapist work together to look at how the patient thinks about herself/himself and the illness, detect unhelpful attitudes, thoughts and mental images about the illness, and to make them accessible to Socratic reasoning. Graded behavioural interventions are planned in order to disconfirm unhelpful beliefs and reverse the spiral of tiredness, demoralization and reduced activity. The treatment is structured according to the general principles of cognitive therapy.

 

Source: d’Elia G. Chronic fatigue syndrome in a cognitive perspective. A therapeutic model. Lakartidningen. 2004 Jan 29;101(5):358-64. [Article in Swedish] http://www.ncbi.nlm.nih.gov/pubmed/14986443

 

Post-traumatic stress disorder among patients with chronic pain and chronic fatigue

Abstract:

BACKGROUND: Fibromyalgia (FM), a chronic pain condition of unknown aetiology often develops following a traumatic event. FM has been associated with post-traumatic stress disorder (PTSD) and major depression disorder (MDD).

METHOD: Patients seen in a referral clinic (N=571) were evaluated for FM and chronic fatigue syndrome (CFS) criteria. Patients completed questionnaires, and underwent a physical examination and a structured psychiatric evaluation. Critical components of the diagnostic criteria of FM (tender points and diffuse pain) and CFS (persistent debilitating fatigue and four of eight associated symptoms) were examined for their relationship with PTSD.

RESULTS: The prevalence of lifetime PTSD was 20% and lifetime MDD was 42%. Patients who had both tender points and diffuse pain had a higher prevalence of PTSD (OR=3.4, 95% CI 2.0-5.8) compared with those who had neither of these FM criteria. Stratification by MDD and adjustment for sociodemographic factors and chronic fatigue revealed that the association of PTSD with FM criteria was confined to those with MDD. Patients with MDD who met both components of the FM criteria had a three-fold increase in the prevalence of PTSD (95% CI 1.5-7.1); conversely, FM patients without MDD showed no increase in PTSD (OR=1.3, 95% CI 0.5-3.2). The components of the CFS criteria were not significantly associated with PTSD.

CONCLUSION: Optimal clinical care for patients with FM should include an assessment of trauma in general, and PTSD in particular. This study highlights the importance of considering co-morbid MDD as an effect modifier in analyses that explore PTSD in patients with FM.

 

Source: Roy-Byrne P, Smith WR, Goldberg J, Afari N, Buchwald D. Post-traumatic stress disorder among patients with chronic pain and chronic fatigue. Psychol Med. 2004 Feb;34(2):363-8. http://www.ncbi.nlm.nih.gov/pubmed/14982142

 

A comparison of pregnancies that occur before and after the onset of chronic fatigue syndrome

Abstract:

BACKGROUND: Many women with chronic fatigue syndrome (CFS) fear that pregnancy will worsen their condition, increase the risks of maternal complications of pregnancy, or threaten the health of their offspring. Little empirical evidence, however, has been published on this matter.

METHODS: A detailed questionnaire was administered to 86 women regarding 252 pregnancies that occurred before or after the onset of CFS and the outcomes of these pregnancies were observed.

RESULTS: During pregnancy, there was no change in CFS symptoms in 29 (41%), an improvement of symptoms in 21 (30%), and a worsening of symptoms in 20 (29%) of 70 subjects. After pregnancy, there was no change in CFS symptoms in 21 (30%), an improvement of symptoms in 14 (20%), and a worsening of symptoms in 35 (20%) of the subjects. The rates of many complications were similar in pregnancies occurring before the onset and in those occurring after the onset of CFS. There was a higher frequency of spontaneous abortions in the pregnancies occurring after, vs before, the onset of CFS (22 [30%] of 73 pregnancies after vs 13 [8%] of 171 before; P<.001), but no differences in the rates of other complications. Developmental delays or learning disabilities were reported more often in the offspring of women who became pregnant after, vs before, the onset of CFS (9 [21%] of 43 children vs 11 [8%] of 139 children; P =.01).

CONCLUSIONS: Pregnancy did not consistently worsen the symptoms of CFS. Most maternal and infant outcomes were not systematically worse in pregnancies occurring after the onset of CFS. The higher rates of spontaneous abortions and of developmental delays in offspring that we observed could be explained by maternal age or parity differences, and should be investigated by larger, prospective studies with control populations.

Comment in: Chronic fatigue syndrome, pregnancy, and Addison disease. [Arch Intern Med. 2004]

 

Source: Schacterle RS, Komaroff AL. A comparison of pregnancies that occur before and after the onset of chronic fatigue syndrome. Arch Intern Med. 2004 Feb 23;164(4):401-4. http://www.ncbi.nlm.nih.gov/pubmed/14980991

 

Cost-effectiveness of cognitive behaviour therapy for patients with chronic fatigue syndrome

Abstract:

BACKGROUND: There is some evidence that cognitive behaviour therapy (CBT) is efficacious in chronic fatigue syndrome (CFS), but little data on its cost-effectiveness.

DESIGN: Prospective economic analysis alongside a randomized clinical trial.

METHODS: CFS patients were randomly assigned to CBT, guided support groups (SG), or the ‘natural course’ (NC, no protocol-based interventions). Patients were treated for 8 months and followed-up for another 6 months. Costs per patient showing clinically significant improvement, based on the CIS fatigue scale, and costs per quality-adjusted life year, were determined for a time period of 14 months.

RESULTS: Data were available for 171 patients at 8 months and for 128 at 14 months. At 8 and 14 months, the percentages of improved patients were 31% and 27% for CBT, 9% and 11% for SG, and 12% and 20% for NC. Mean QALYs gained at 14 months were, for CBT, SG and NC, respectively, 0.0737, -0.0018 and 0.0458. CBT and SG mean treatment costs were euro1490 and euro424. Other medical costs for CBT, SG, and NC, respectively, were euro324, euro623 and euro412 for the first period, and euro232, euro561 and euro378 for the second period. Non-medical costs for these periods for CBT, SG and NC were euro262, euro550, euro427 and euro226, euro439, euro287, respectively. Productivity costs were considerable, but not significantly different between groups.

DISCUSSION: CBT was less costly and more effective than SG. Compared to NC, the baseline incremental cost-effectiveness of CBT was euro20 516 per CFS patient showing clinically significant improvement, and euro21 375 per QALY. The bootstrap ratios showed considerable uncertainty regarding the results. Future research should focus on productivity costs, and follow patients prospectively over a longer period.

Comment in:

Cost-effectiveness of cognitive behaviour therapy for patients with chronic fatigue syndrome. [QJM. 2004]

Cost-effectiveness of cognitive behaviour therapy for patients with chronic fatigue syndrome. [QJM. 2004]

 

Source: Severens JL, Prins JB, van der Wilt GJ, van der Meer JW, Bleijenberg G. Cost-effectiveness of cognitive behaviour therapy for patients with chronic fatigue syndrome. QJM. 2004 Mar;97(3):153-61. http://qjmed.oxfordjournals.org/content/97/3/153.long (Full article)

 

Patterns of cardiovascular reactivity in disease diagnosis

Abstract:

BACKGROUND: Aberrations of cardiovascular reactivity (CVR), an expression of autonomic function, occur in a number of clinical conditions, but lack specificity for a particular disorder. Recently, a CVR pattern particular to chronic fatigue syndrome was observed.

AIM: To assess whether specific CVR patterns can be described for other clinical conditions.

METHODS: Six groups of patients, matched for age and gender, were evaluated with a shortened head-up tilt test: patients with chronic fatigue syndrome (CFS) (n = 20), non-CFS fatigue (F) (n = 15), neurally-mediated syncope (SY) (n = 21), familial Mediterranean fever (FMF) (n = 17), psoriatic arthritis (PSOR) (n = 19) and healthy subjects (H) (n = 20). A 10-min supine phase was followed by recording 600 cardiac cycles on tilt (5-10 min). Beat-to-beat heart rate (HR) and pulse transit time (PTT) were measured. Results were analysed using conventional statistics, recurrence plot analysis and fractal analysis.

RESULTS: Multivariate analysis evaluated independent predictors of the CVR in each patient group vs. all other groups. Based on these predictors, equations were determined for a linear discriminant score (DS) for each group. The best sensitivities and specificities of the DS, consistent with disease-related phenotypes of CVR, were noted in the following groups: CFS, 90.0% and 60%; SY, 93.3% and 62.5%; FMF, 90.1% and 75.4%, respectively.

DISCUSSION: Pathological disturbances may alter cardiovascular reactivity. Our data support the existence of disease-related CVR phenotypes, with implications for pathogenesis and differential diagnosis.

 

Source: Naschitz JE, Rosner I, Rozenbaum M, Fields M, Isseroff H, Babich JP, Zuckerman E, Elias N, Yeshurun D, Naschitz S, Sabo E. Patterns of cardiovascular reactivity in disease diagnosis. QJM. 2004 Mar;97(3):141-51. http://qjmed.oxfordjournals.org/content/97/3/141.long (Full article)