Exploring the validity of the chalder fatigue scale in chronic fatigue syndrome

doi:10.1016/S0022-3999(98)00022-1

Journal of Psychosomatic Research

Volume 45, Issue 5, November 1998, Pages 411-417

https://doi.org/10.1016/S0022-3999(98)00022-1 Get rights and content

Abstract

The Chalder fatigue scale is widely used to measure physical and mental fatigue in chronic fatigue syndrome patients, but the constructs of the scale have not been examined in this patient sample. We examined the constructs of the 14-item fatigue scale in a sample of 136 chronic fatigue syndrome patients through principal components analysis, followed by correlations with measures of subjective and objective cognitive performance, physiological measures of strength and functional work capacity, depression, anxiety, and subjective sleep difficulties. There were four factors of fatigue explaining 67% of the total variance. Factor 1 was correlated with subjective everyday cognitive difficulties, concentration difficulties, and a deficit in paired associate learning. Factor 2 was correlated with difficulties in maintaining sleep. Factor 3 was inversely correlated with grip strength, peak VO₂, peak heart rate, and peak functional work capacity. Factor 4 was correlated with interview and self-rated measures of depression. The results support the validity of mental and physical fatigue subscales and the dropping of the “loss of interest” item in the 11-item version of the fatigue scale.

Introduction

Chalder et al. [1] developed a brief self-rated 14-item instrument that measures the symptoms of mental and physical fatigue that are thought to be pathognomonic to chronic fatigue syndrome (CFS) 2, 3. The Chalder fatigue scale has been used recently in treatment outcome studies in CFS patients 4, 5. The validity and reliability of their scale has been examined in general practice attenders [1], but not before in CFS patients. However, inspection of the scale raises some questions concerning the validity of some items and its subdivision into physical (eight items) and mental fatigue subscales (six items). For instance, the mental fatigue item “loss of interest” is a cardinal symptom of depression [6]. The item “feeling sleepy or drowsy” could be related to problems with maintaining sleep at night [7] rather than physical fatigue items related to loss of stamina or strength, or mental fatigue symptoms such as poor concentration and word-finding difficulties. The physical fatigue subscale item “problems starting things” could be due to loss of motivation or an inability to organize oneself instead of a physical problem. We examined the validity of the constructs of physical and mental fatigue of the 14-item Chalder fatigue scale against a variety of subjective and objective measures of physical and mental functioning and mood and sleep disturbance.

Section snippets

Subjects

Patients with CFS over the age of 18 years were recruited from consecutive referrals to a university department of medicine out-patient clinic from consultant physicians and general practitioners across northwestern England and northern Wales. All patients were medically assessed by a doctor under the direct supervision of a consultant physician. A full history, physical examination, and laboratory investigations (full blood count, ESR, biochemistry, creatinine phosphokinase, c-reactive

Results

Two hundred twenty-seven patients were assessed for eligibility into a treatment trial of graduated aerobic exercise and fluoxetine, which will be separately reported. Sixty-two did not fulfill criteria for CFS. Of the remaining 165, 25 did not consent to the treatment trial, 3 could not come off antidepressants, and 1 required other medical treatment first. The 136 CFS patients not taking psychotropic medication who started the treatment trial completed the assessments examined in the current

Discussion

In contrast to the two constructs of fatigue obtained by Chalder et al. [1] in a general practice sample with the 14-item fatigue scale, we extracted four constructs of fatigue in CFS patients. The results support the validity of the less widely used 11-item version of the Chalder fatigue scale [1], which drops the “loss of interest” item—which was strongly correlated with interview and self-rated depression, but not any other measure of mental or physical functioning. The 11-item fatigue scale

Acknowledgements

Acknowledgments—This study was supported by a grant from the Linbury Trust. We would like to thank Drs. David Pearson, Ian Campbell, Paul Strickland, Trudie Roberts, and Professor Louis Appleby for assessments or use of their equipment, and Brian Faragher for statistical advice.

References (18)

T Chalder et al.
Development of a fatigue scale
J Psychosom Res
(1993)
R Morriss et al.
The relationship of sleep difficulties to fatigue, mood and disability in chronic fatigue syndrome
J Psychosom Res
(1997)
M.C Sharpe et al.
A report—chronic fatigue syndromeguidelines for research
J R Soc Med
(1991)
K Fukuda et al.
The chronic fatigue syndromea comprehensive approach to definition and study. (International Chronic Fatigue Syndrome Group)
Ann Intern Med
(1994)
A Deale et al.
Cognitive behaviour therapy for chronic fatigue syndromea randomised controlled trial
Am J Psychiatry
(1997)
K.Y Fulcher et al.
Randomised controlled trial of grade exercise in patients with the chronic fatigue syndrome
BMJ
(1997)
American Psychiatric Association
Diagnostic and statistical manual
(1987)
R.K Morriss et al.
Abnormalities of sleep in patients with chronic fatigue syndrome
BMJ
(1993)
A.S Zigmond et al.
The Hospital Anxiety and Depression Scale (HAD)
Acta Psychiatrica Scand
(1983)

There are more references available in the full text version of this article.

Cited by (134)

Symptom clusters and characteristics of cervical cancer patients receiving concurrent chemoradiotherapy: A cross-sectional study
2023, Heliyon
Cervical cancer patients have a high symptom burden during concurrent chemoradiotherapy (CCRT) and urgently need precise symptom management strategies. Nonetheless, the symptom profile and influencing factors are unclear.
A total of 234 patients with cervical cancer who underwent CCRT in a tertiary care hospital clinical oncology center in Guangxi Zhuang Autonomous Region from March 2022 to March 2023 were included in the study. The general information questionnaire, M.D. Anderson symptom inventory, Fatigue Scale-14, Pittsburgh Sleep Quality Index, and grip strength test were used for the investigation. Symptom clusters were extracted by exploratory factor analysis, and latent profile analysis was performed using Mplus 8.0 software. Multinomial logistic regression was used to explore the factors influencing the potential categories of symptom clusters.
Exploratory factor analysis extracted four symptom clusters: a fatigue-related symptom cluster, a gastrointestinal-related symptom cluster, a mood-related symptom cluster, and a physical-related symptom cluster, of which the fatigue-related symptom cluster was more severe and was divided into three potential categories: low fatigue-good muscle fitness type (25.63%), general fatigue-moderate muscle fitness type (68.37%) and high fatigue-low muscle fitness type (6%). Multinomial logistic regression analysis showed that hemoglobin levels, tumor stage, absence of complications, and unemployment were factors influencing the fatigue-related symptom cluster in patients undergoing CCRT for cervical cancer.
Cervical cancer patients experience multiple symptom clusters during CCRT. Different characteristics appeared in different clusters. Among them, fatigue-related symptom clusters were more severe and heterogeneous. In clinical practice, we should pay attention to and use high symptom feature predictors, focusing on the core symptoms that play a dominant role, achieving early identification and management, and reducing patients' symptom burden.
Long-term symptom severity and clinical biomarkers in post-COVID-19/chronic fatigue syndrome: results from a prospective observational cohort
2023, eClinicalMedicine
Post-COVID-19 syndrome (PCS) is characterised by a wide range of symptoms, primarily fatigue and exertion intolerance. While disease courses in the early months post-infection have been well-described, the long-term health consequences for patients with PCS with disabling fatigue remain unclear.
In this prospective observational cohort study, we evaluated symptom severity and various biomarkers, including hand grip strength (HGS), cardiovascular function, and laboratory parameters, in 106 patients with PCS with moderate to severe fatigue and exertion intolerance at three time points after infection (3–8, 9–16, and 17–20 months). The study was conducted at the Charité’s Fatigue Centre and the Charité’s outpatient clinic for neuroimmunology at Berlin, Germany from July 16, 2020, to February 18, 2022. A subset of patients (PCS-ME/CFS) met the diagnostic criteria for myalgic encephalomyelitis/chronic fatigue syndrome according to the Canadian Consensus Criteria (CCC). The aim was to determine differences in the disease course between the two patient groups (i.e., PCS vs PCS-ME/CFS) and identify correlating biomarkers.
Patients with PCS-ME/CFS reported persistently high severity of most symptoms up to 20 months after infection, while patients with PCS showed overall health improvement. Although fatigue and post-exertional malaise (PEM), hallmarks of post-infectious fatigue syndromes, were still evident in both groups, they remained more pronounced in PCS-ME/CFS. Inflammatory biomarkers decreased in both groups, but not antinuclear antibodies. Lower HGS at onset correlated with symptom persistence, particularly in patients with PCS-ME/CFS.
Our findings suggest that PCS can persist beyond 20 months post-infection and encompass the full scope of post-infectious ME/CFS as defined by the CCC. Sub-classifying patients with PCS based on the CCC can assist in the management and monitoring of patients with PCS-ME/CFS due to their persistently higher symptom severity.
C. S. was supported by a grant from the Weidenhammer-Zoebele Foundation. F. K. was supported by the Volkswagen Foundation.
Persistent somatic symptoms are key to individual illness perception at one year after COVID-19 in a cross-sectional analysis of a prospective cohort study
2023, Journal of Psychosomatic Research
Subjective illness perception (IP) can differ from physician's clinical assessment results. Herein, we explored patient's IP during coronavirus disease 2019 (COVID-19) recovery.
Participants of the prospective observation CovILD study (ClinicalTrials.gov: NCT04416100) with persistent somatic symptoms or cardiopulmonary findings one year after COVID-19 were analyzed (n = 74). Explanatory variables included demographic and comorbidity, COVID-19 course and one-year follow-up data of persistent somatic symptoms, physical performance, lung function testing, chest computed tomography and trans-thoracic echocardiography. Factors affecting IP (Brief Illness Perception Questionnaire) one year after COVID-19 were identified by regularized modeling and unsupervised clustering.
In modeling, 33% of overall IP variance (R²) was attributed to fatigue intensity, reduced physical performance and persistent somatic symptom count. Overall IP was largely independent of lung and heart findings revealed by imaging and function testing. In clustering, persistent somatic symptom count (Kruskal-Wallis test: η² = 0.31, p < .001), fatigue (η² = 0.34, p < .001), diminished physical performance (χ² test, Cramer V effect size statistic: V = 0.51, p < .001), dyspnea (V = 0.37, p = .006), hair loss (V = 0.57, p < .001) and sleep problems (V = 0.36, p = .008) were strongly associated with the concern, emotional representation, complaints, disease timeline and consequences IP dimensions.
Persistent somatic symptoms rather than abnormalities in cardiopulmonary testing influence IP one year after COVID-19. Modifying IP represents a promising innovative approach to treatment of post-COVID-19 condition. Besides COVID-19 severity, individual IP should guide rehabilitation and psychological therapy decisions.
Efficacy and tolerability of an endogenous metabolic modulator (AXA1125) in fatigue-predominant long COVID: a single-centre, double-blind, randomised controlled phase 2a pilot study
2023, eClinicalMedicine
‘Long COVID’ describes persistent symptoms, commonly fatigue, lasting beyond 12 weeks following SARS-CoV-2 infection. Potential causes include reduced mitochondrial function and cellular bioenergetics. AXA1125 has previously increased β-oxidation and improved bioenergetics in preclinical models along with certain clinical conditions, and therefore may reduce fatigue associated with Long COVID. We aimed to assess the efficacy, safety and tolerability of AXA1125 in Long COVID.
Patients with fatigue-dominant Long COVID were recruited in this single-centre, double-blind, randomised controlled phase 2a pilot study completed in the UK. Patients were randomly assigned (1:1) using an Interactive Response Technology to receive either AXA1125 or matching placebo in a clinical-based setting. Each dose (33.9 g) of AXA1125 or placebo was administered orally in a liquid suspension twice daily for four weeks with a two-week follow-up period. The primary endpoint was the mean change from baseline to day 28 in the phosphocreatine (PCr) recovery rate following moderate exercise, assessed by ³¹P-magnetic resonance spectroscopy (MRS). All patients were included in the intention to treat analysis. This trial was registered at ClinicalTrials.gov, NCT05152849.
Between December 15th 2021, and May 23th 2022, 60 participants were screened, and 41 participants were randomised and included in the final analysis. Changes in skeletal muscle phosphocreatine recovery time constant (τ_PCr) and 6-min walk test (6MWT) did not significantly differ between treatment (n = 21) and placebo group (n = 20). However, treatment with AXA1125 was associated with significantly reduced day 28 Chalder Fatigue Questionnaire [CFQ-11] fatigue score when compared with placebo (least squares mean difference [LSMD] −4.30, 95% confidence interval (95% CI) −7.14, −1.47; P = 0.0039). Eleven (52.4%, AXA1125) and four (20.0%, placebo) patients reported treatment-emergent adverse events; none were serious or led to treatment discontinuation.
Although treatment with AXA1125 did not improve the primary endpoint (τ_PCr-measure of mitochondrial respiration), when compared to placebo, there were significant improvements in fatigue-based symptoms among patients living with Long COVID following a four-week treatment period. Further multicentre studies are needed to validate our findings in a larger cohort of patients with fatigue-dominant Long COVID.
Axcella Therapeutics.
Regional gray matter volume correlates to physical and mental fatigue in healthy middle-aged adults
2022, Neuroimage: Reports
Previous studies on neural/molecular mechanisms of fatigue focused on a variety of brain functions, morphological changes, and neurochemical functions such as neurotransmitter and neuroimmune dynamics. However, MRI morphological changes were adopted primarily to compare patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and healthy controls. A few studies have been done on healthy subjects with fatigue scores; one study with 63 adults (their ages of 53.2 ± 8.3) showed the gray matter volume (GMV) reduction in good correlation with a higher score of fatigue. The other one with university students (their ages of 20.7 ± 1.8) demonstrated no significant correlation between regional GMV (rGMV) and fatigue severity. To elucidate the brain structural underpinning in parallel with fatigue development, a large number of healthy middle-aged adults (n = 1873; aged 54.1 ± 5.4) without ME/CFS were recruited, and the correlation between both rGMV in the cerebrum including basal ganglia and Chalder's fatigue questionnaire (CFQ) with physical and mental categories were investigated. A higher CFQ score denotes a higher perceived fatigue level by the participant. The physical fatigue scores of CFQ showed a significantly negative correlation (i.e., smaller rGMV for higher CFQ score) with the volume of the right planum temporale and supplemental motor cortex (SMC), while the left putamen, middle temporal gyrus (MTG), parietal operculum, and right precentral gyrus showed a significantly positive correlation (i.e., bigger rGMV for higher CFQ score). In the mental fatigue scores, the right SMC and left lateral orbital gyrus (LOG) showed a significantly negative correlation, while only the left fusiform gyrus showed a significantly positive correlation. In total scores of (both physical and mental) fatigue, the right SMC and orbital part of the inferior frontal gyrus (OIFG) showed a negative correlation, while the left putamen and MTG showed a positive correlation. Therefore, the right SMC may play a critical role in fatigue progression because of the only common factor among physical, mental, and total fatigue. The left putamen may play a compensatory role with a positive correlation to physical and total fatigue. Additionally, identifying the other gray matter regions that positively or negatively correlated to CFQ of healthy adults may help deepen the understanding of early-stage fatigue progression, leading to the future establishment of preventive measures through volumetrics by using MRI.
Associations Between Demographic Variables, Psychosocial Health, Quality of Life, and Happiness in the Context of COVID-19
2024, Applied Research in Quality of Life

View all citing articles on Scopus

View full text

Original ArticleExploring the validity of the chalder fatigue scale in chronic fatigue syndrome

Abstract

Introduction

Section snippets

Subjects

Results

Discussion

Acknowledgements

J Psychosom Res

J Psychosom Res

A report—chronic fatigue syndromeguidelines for research

J R Soc Med

The chronic fatigue syndromea comprehensive approach to definition and study. (International Chronic Fatigue Syndrome Group)

Ann Intern Med

Cognitive behaviour therapy for chronic fatigue syndromea randomised controlled trial

Am J Psychiatry

Randomised controlled trial of grade exercise in patients with the chronic fatigue syndrome

BMJ

Diagnostic and statistical manual

Abnormalities of sleep in patients with chronic fatigue syndrome

BMJ

The Hospital Anxiety and Depression Scale (HAD)

Acta Psychiatrica Scand

Original Article
Exploring the validity of the chalder fatigue scale in chronic fatigue syndrome