Category: Methodology

An approach to persons with chronic fatigue syndrome based on the model of human occupation: part one, impact on occupational performance and participation

Abstract:

Chronic fatigue syndrome (CFS) is a prevalent and disabling condition that involves six or more months of unexplained fatigue severe enough to interfere with previous levels of occupational, educational, and/or social performance. The fatigue is accompanied by at least four of eight additional physical and cognitive symptoms (Fukuda et al., 1994). This paper conceptualizes the multiple factors that affect occupational adaptation in persons with CFS. The Model of Human Occupation (MOHO) if used as a framework for understanding the synergistic and evolving relationships between motivation, roles, habits, performance capacities, and the environment as they influence individuals with CFS. Examples from the literature, autobiographical accounts, and from practice experience are used to illustrate the experience and impact of CFS on everyday life.

 

Source: Taylor RR, Kielhofner GW, Abelenda J, Colantuono K, Fong T, Heredia R, Kulkarni S, Vazquez E. An approach to persons with chronic fatigue syndrome based on the model of human occupation: part one, impact on occupational performance and participation. Occup Ther Health Care. 2003;17(2):47-61. doi: 10.1080/J003v17n02_04. http://www.ncbi.nlm.nih.gov/pubmed/23944637

 

Relationship between chronic fatigue and subjective symptoms of fatigue with performance status (P.S.) and subjective fatigue scale for young adults (SFS-Y)

Abstract:

OBJECTIVE: Today, fatigue complaints in adolescence are regarded as an issue for young adults as they may progress to the chronic fatigue syndrome. The purpose of this study was to examine the relationships between chronic fatigue based on self-reported performance states (P.S.) and subjective symptoms of fatigue assessed with a fatigue scale for young adults (SFS-Y).

METHOD: The SFS-Y consisted of 24 item questions represonting 6 sub-scales, for difficulty in concentrated thinking, languor, reduced activation, reduced motivation, drowsiness and feeling of physical disintegration. The SFS-Y and for assessing fatigue symptoms and P.S. for chronic fatigue were administered to 548 male and female students aged 15-18 yr and to 608 male students aged 16-18 yr, respectively. Discriminant analysis and a logistic analysis model were employed to define the relevance of subjective symptoms of fatigue to chronic fatigue.

RESULTS: It was determined that the SFS-Y can discliminate P.S. with high probability (74.0-81.4%), with accuracy beyond a fixed level. In particular, the correlation with “difficulty in concentrated thinking” was high.

CONCLUSION: It was judged that the SFS-Y is effective as an index for discrimination of chronic fatigue in young adults with a particularly high relationship between “difficulty in centrated thinking” and chronic fatigue.

 

Source: Kobayashi H, Demura S. Relationship between chronic fatigue and subjective symptoms of fatigue with performance status (P.S.) and subjective fatigue scale for young adults (SFS-Y). Nihon Koshu Eisei Zasshi. 2002 Oct;49(10):1062-9. [Article in Japanese] http://www.ncbi.nlm.nih.gov/pubmed/12462040

 

Fractal analysis and recurrence quantification analysis of heart rate and pulse transit time for diagnosing chronic fatigue syndrome

Abstract:

This study aimed to develop a method to distinguish between the cardiovascular reactivity in chronic fatigue syndrome (CFS) and other patient populations.

Patients with CFS (n = 23), familial Mediterranean fever (n = 15), psoriatic arthritis (n = 10), generalized anxiety disorder (n = 12), neurally mediated syncope (n = 20), and healthy subjects (n = 20) were evaluated with a shortened head-up tilt test (HUTT). A 10-minute supine phase of the HUTT was followed by recording 600 cardiac cycles on tilt, i. e., 5 to 10 minutes. Beat-to-beat heart rate (HR) and pulse transit time (PTT) were acquisitioned. Data were processed by recurrence plot and fractal analysis. Fifty-two variables were calculated in each subject.

On multivariate analysis, the best predictors of CFS were HR-tilt-R/L, PTT-tilt-R/L, HR-supine-DET, PTT-tilt-WAVE, and HR-tilt-SD. Based on these predictors, the ‘Fractal & Recurrence Analysis-based Score’ (FRAS) was calculated: FRAS = 76.2 + 0.04*HR-supine-DET – 12.9*HR-tilt-R/L – 0.31*HR-tilt-SD – 19.27*PTT-tilt-R/L – 9.42* PTT-tilt-WAVE. The best cut-off differentiating CFS from the control population was FRAS = + 0.22. FRAS > + 0.22 was associated with CFS (sensitivity 70 % and specificity 88 %). The cardiovascular reactivity received mathematical expression with the aid of the FRAS. The shortened HUTT was well tolerated. The FRAS provides objective criteria which could become valuable in the assessment of CFS.

Comment in: Chronic fatigue syndrome and hidden happenings of the heartbeat. [Clin Auton Res. 2002]

 

Source: Naschitz JE, Sabo E, Naschitz S, Rosner I, Rozenbaum M, Priselac RM, Gaitini L, Zukerman E, Yeshurun D. Fractal analysis and recurrence quantification analysis of heart rate and pulse transit time for diagnosing chronic fatigue syndrome. Clin Auton Res. 2002 Aug;12(4):264-72. http://www.ncbi.nlm.nih.gov/pubmed/12357280

 

Latent class analysis of symptoms associated with chronic fatigue syndrome and fibromyalgia

Abstract:

BACKGROUND: Chronic fatigue syndrome and fibromyalgia continue to be perplexing conditions of unknown validity. Aetiological and symptomatic heterogeneity is likely and the distinctiveness of these disorders remains unclear. Our aims were to investigate empirically symptomatic heterogeneity in chronic fatigue syndrome and fibromyalgia.

METHODS: Latent class analysis was applied to data from 646 patients who met accepted criteria for chronic fatigue syndrome and/or fibromyalgia who were systematically evaluated at a specialist fatigue clinic. Thirty-two symptoms commonly found in chronic fatigue syndrome and fibromyalgia were entered into the latent class analysis.

RESULTS: We chose to interpret a four class solution. The classes appeared to differ in a graded fashion (rather than qualitatively) for symptom endorsements, pre-morbid characteristics, and co-morbidity with panic disorder and major depression.

CONCLUSIONS: These results were unexpected given the usual assumption of the distinctiveness of chronic fatigue syndrome and fibromyalgia. These results support a conceptualization of chronic fatigue syndrome and fibromyalgia as being characterized by greater similarities than differences.

 

Source: Sullivan PF, Smith W, Buchwald D. Latent class analysis of symptoms associated with chronic fatigue syndrome and fibromyalgia. Psychol Med. 2002 Jul;32(5):881-8. http://www.ncbi.nlm.nih.gov/pubmed/12171382

 

A rating scale for fibromyalgia and chronic fatigue syndrome (the FibroFatigue scale)

Abstract:

OBJECTIVE: To construct an observer’s rating scale sensitive to change for measuring severity and treatment outcome in fibromyalgia (FM) and chronic fatigue syndrome (CFS) patients.

METHODS: A selection of items from the Comprehensive Psychopathological Rating Scale (CPRS) were repeatedly rated and used as outcome measure of a 24-week treatment study. In the study 100 women, fulfilling the criteria for both FM and CFS, received intermittent injections of a staphylococcus toxoid or placebo. Nine CPRS-items with high baseline incidence (cutoff 70%) were extracted and validated against global ratings and the Fibromyalgia Impact Questionnaire (FIQ). The fibromyalgia and chronic fatigue syndrome rating scale (the FibroFatigue scale) was thereafter formed based upon the extracted items and three supplemented ones. The interrater reliability was tested in 27 consecutive patients of both sexes.

RESULTS: The FibroFatigue scale is an observer’s rating scale with 12 items measuring pain, muscular tension, fatigue, concentration difficulties, failing memory, irritability, sadness, sleep disturbances, and autonomic disturbances (items derived from the CPRS) and irritable bowel, headache, and subjective experience of infection (new items). There was a statistically significant correlation between the CPRS-extracted items and global ratings as well as with the FIQ. The interrater reliability of the new scale was excellent (correlation coefficient.98), irrespective of the patients’ gender.

CONCLUSION: The FibroFatigue scale seems to be a reliable and valid measuring instrument with capacity to monitor symptom severity and change during treatment of FM/CFS patients.

 

Source: Zachrisson O, Regland B, Jahreskog M, Kron M, Gottfries CG. A rating scale for fibromyalgia and chronic fatigue syndrome (the FibroFatigue scale). J Psychosom Res. 2002 Jun;52(6):501-9. http://www.ncbi.nlm.nih.gov/pubmed/12069875

 

The Family Response Questionnaire: a new scale to assess the responses of family members to people with chronic fatigue syndrome

Abstract:

OBJECTIVE: Family responses to patients with chronic fatigue syndrome (CFS) may influence the course of the disorder and family members themselves are likely to be adversely affected. However, the beliefs and responses of relatives of CFS patients have been under-researched. The aim of this study was to produce an easy-to-administer questionnaire to assess the responses of family members to people with CFS.

METHODS: Seventy-eight people, all close relatives of (physician-diagnosed) CFS sufferers, completed the first version of the Family Response Questionnaire (FRQ).

RESULTS: Examination of the correlation matrix and a cluster analysis of the items support four scales rather than the original five. The four response scales were labelled: sympathetic-empathic, active engagement, rejecting-hostile, and concern with self. Measures of test-retest and internal reliability were high. Participants found the items both comprehensible and relevant to their experiences of living with people with CFS.

CONCLUSION: The new version of the FRQ will be useful in further examination of the responses of CFS on individuals and their families.

 

Source: Cordingley L, Wearden A, Appleby L, Fisher L. The Family Response Questionnaire: a new scale to assess the responses of family members to people with chronic fatigue syndrome. J Psychosom Res. 2001 Aug;51(2):417-24. http://www.ncbi.nlm.nih.gov/pubmed/11516763

 

Evaluation of a recombinant line blot for diagnosis of Epstein-Barr Virus compared with ELISA, using immunofluorescence as reference method

Abstract:

A commercial line blot using recombinant antigens was compared with a commercial ELISA and ‘in-house’ IFA (reference test). Two panels were evaluated: Panel A was selected to distinguish between primary infections (89), past infections (20) and seronegatives (8) in immunocompetent individuals. In panel B, patients with a high number of reactivations were included: immunosuppressed patients (37), lymphoma (19), nasopharyngeal carcinoma (10), chronic fatigue syndrome (14). Blood donors (43) and cross-reactive sera (29) were added as controls.

Line blot and IFA were concordant in 94% of primary infections, 100% of seronegatives and 100% of past infections, similar to ELISA. Results differed significantly with regard to reactivations. When compared with IFA, the incidence of reactivations was overestimated by the blot, 24 and 58% in blood donors and cross-reactive sera, respectively. ELISA showed a similar problems with 21 and 34% indeterminate results, respectively.

The line blot is easy to carry out, has a good concordance with the reference IFA for primary infections, and is, therefore, a sufficient choice for distinguishing primary infection from seronegative and past infection. EBV reactivation assessment will require other methods such as EBV viral load.

 

Source: Gärtner BC, Fischinger JM, Roemer K, Mak M, Fleurent B, Mueller-Lantzsch N. Evaluation of a recombinant line blot for diagnosis of Epstein-Barr Virus compared with ELISA, using immunofluorescence as reference method. J Virol Methods. 2001 Apr;93(1-2):89-96. http://www.ncbi.nlm.nih.gov/pubmed/11311347

 

Screening for prolonged fatigue syndromes: validation of the SOFA scale

Abstract:

BACKGROUND: The identification of syndromes characterised by persistent and disabling mental and/or physical fatigue is of renewed interest in psychiatric epidemiology. This report details the development of two specific instruments: the SOFA/CFS for identification of patients with chronic fatigue syndrome (CFS) in specialist clinics and the SOFA/GP for identification of prolonged fatigue syndromes (PFS) in community and primary care settings.

METHODS: Patients with clinical diagnoses of CFS (n = 770) and consecutive attenders at primary care (n = 1593) completed various self-report questionnaires to assess severity of current fatigue-related symptoms and other common somatic and psychological symptoms. Quality receiver operating characteristic curves were used to derive appropriate cut-off scores for each of the instruments. Comparisons with other self-report measures of anxiety, depression and somatic distress are noted. Various multivariate statistical modelling techniques [latent class analysis (LCA), longitudinal LCA] were utilised to define the key features of PFS and describe its longitudinal characteristics.

RESULTS: The SOFA/CFS instrument performs well in specialist samples likely to contain a high proportion of patients with CFS disorders. Cut-off scores of either 1/2 or 2/3 can be used, depending on whether the investigators wish to preferentially emphasise false-negatives or false-positives. Patients from these settings can be thought of as consisting not only of those with a large number of unexplained medical symptoms, but also those with rather specific musculoskeletal and pain syndromes. The SOFA/GP instrument has potential cut-off scores of 1/2 or 2/3, with the latter preferred as it actively excludes all non-PFS cases (sensitivity = 81%, specificity = 100%). Patients with these syndromes in the community represent broader sets of underlying classes, with the emergence of not only musculoskeletal and multisymptomatic disorders, but also persons characterised by significant cognitive subjective impairment. Twelve-month longitudinal analyses of the primary care sample indicated that the underlying class structure was preserved over time. Comparisons with other measures of psychopathology indicated the relative independence of these constructs from conventional notions of anxiety and depression.

CONCLUSIONS: The SOFA/GP instrument (which is considerably modified from the SOFA/CFS in terms of anchor points for severity and chronicity) is preferred for screening in primary care and community settings. Patients with PFS and CFS present a range of psychopathology that differs in its underlying structure, cross-sectionally and longitudinally, from coventional notions of anxiety and depression.

 

Source: Hadzi-Pavlovic D, Hickie IB, Wilson AJ, Davenport TA, Lloyd AR, Wakefield D. Screening for prolonged fatigue syndromes: validation of the SOFA scale. Soc Psychiatry Psychiatr Epidemiol. 2000 Oct;35(10):471-9. http://www.ncbi.nlm.nih.gov/pubmed/11127722

 

Fatigue rating scales: an empirical comparison

Abstract:

BACKGROUND: There has been limited research comparing the efficacy of different fatigue rating scales for use with individuals with chronic fatigue syndrome (CFS). This investigation explored relationships between two commonly-used fatigue rating scales in CFS research, the Fatigue Scale and the Fatigue Severity Scale. Theoretically, these scales have been described as measuring different aspects of the fatigue construct. The Fatigue Scale was developed as a measure of the severity of specific fatigue-related symptoms, while the Fatigue Severity Scale was designed to assess functional outcomes related to fatigue.

METHODS: Associations of these scales with the eight definitional symptoms of CFS and with eight domains of functional disability were examined separately in: (1) an overall sample of individuals with a wide range of fatigue severity and symptomatology; (2) a subsample of individuals with CFS-like symptomatology, and, (3) a subsample of healthy controls.

RESULTS: Findings revealed that both scales are appropriate and useful measures of fatigue-related symptomatology and disability within a general population of individuals with varying levels of fatigue. However, the Fatigue Severity Scale appears to represent a more accurate and comprehensive measure of fatigue-related severity, symptomatology, and functional disability for individuals with CFS-like symptomatology.

 

Source: Taylor RR, Jason LA, Torres A. Fatigue rating scales: an empirical comparison. Psychol Med. 2000 Jul;30(4):849-56. http://www.ncbi.nlm.nih.gov/pubmed/11037093

 

The development of the Chronic Fatigue Syndrome Attitudes Test. A psychometric analysis

Abstract:

Chronic Fatigue Syndrome (CFS) is characterized by debilitating symptoms including persistent or relapsing fatigue. As a result of CFS, some individuals experience significant stigma that is attached to this illness. Many medical professionals are skeptical of the validity of the illness, and employers often fail to appreciate the seriousness of the symptoms. Although negative attitudes greatly affect the lives of individuals with CFS, there is presently no measurement of attitudes toward this illness and people who have CFS. The purpose of the present studies was to create a scale that measures attitudes toward individuals with CFS–the Chronic Fatigue Attitudes Test (CAT)–and to assess the scale’s reliability and validity. The 13-item scale was created using several constructs outlined in the literature regarding negative attitudes toward people with CFS, disabilities, and AIDS. Theoretical implications of the findings and the utility of the CAT are discussed.

 

Source: Shlaes JL, Jason LA, Ferrari JR. The development of the Chronic Fatigue Syndrome Attitudes Test. A psychometric analysis. Eval Health Prof. 1999 Dec;22(4):442-65. http://www.ncbi.nlm.nih.gov/pubmed/10623400