Neuropsychological functioning, illness perception, mood and quality of life in chronic fatigue syndrome, autoimmune thyroid disease and healthy participants

Abstract:

BACKGROUND: This study attempted to longitudinally investigate neuropsychological function, illness representations, self-esteem, mood and quality of life (QoL) in individuals with chronic fatigue syndrome (CFS) and compared them with both healthy participants and a clinical comparison group of individuals with autoimmune thyroid disease (AITD).

METHOD: Neuropsychological evaluation was administered at two time points, five weeks apart. Twenty-one individuals with CFS, 20 individuals with AITD and 21 healthy participants were matched for age, pre-morbid intelligence, education level and socio-economic status (SES). All groups also completed measures of illness perceptions, mood, self-esteem and QoL at both time points.

RESULTS: The CFS group showed significantly greater impairment on measures of immediate and delayed memory, attention and visuo-constructional ability, and reported significantly higher levels of anxiety and depression. After controlling for the effects of mood, the CFS group still demonstrated significant impairment in attention. The CFS group also reported significantly lower self-reported QoL than the AITD and healthy participants. In terms of illness perceptions, the AITD group believed that their condition would last longer, that they had more treatment control over their condition, and reported less concern than the CFS group.

CONCLUSIONS: These results suggest that the primary cognitive impairment in CFS is attention and that this is not secondary to affective status. The lower treatment control perceptions and greater illness concerns that CFS patients report may be causally related to their affective status.

 

Source: Dickson A, Toft A, O’Carroll RE. Neuropsychological functioning, illness perception, mood and quality of life in chronic fatigue syndrome, autoimmune thyroid disease and healthy participants. Psychol Med. 2009 Sep;39(9):1567-76. doi: 10.1017/S0033291708004960. Epub 2009 Jan 15. https://www.ncbi.nlm.nih.gov/pubmed/19144216

 

Influenza vaccination: is it appropriate in chronic fatigue syndrome?

Abstract:

Chronic fatigue syndrome (CFS) is a recognized clinical illness of unknown cause and pathophysiologic mechanisms. Immunizing patients against influenza would seem to be a prudent strategy since infection has been associated with symptom exacerbation. However, patients with CFS have demonstrated variable abnormalities in the immune system, the clinical significance of which is unclear. Anecdotal information has suggested that, due to the etiologic uncertainty surrounding CFS, many patients reject immunization, fearful of untoward effects. This article attempts to clarify the situation by reviewing immunologic findings in CFS and influenza vaccines in current use. Results from a recent survey of perceptions of patients with CFS regarding immunization revealed that 31% felt immunization was neither safe nor beneficial. This opinion was universal in those patients who had never received influenza vaccine. Among patients who had received vaccine and experienced an adverse effect, 26% felt the vaccine was safe and 28% felt it was beneficial. Among those who had received vaccine without an adverse effect, 45% believed the vaccine was safe, and 55% felt it was effective. CFS patients as a group expressed concern that influenza vaccine would alter an already dysfunctional immune system, or worsen CFS symptoms.

Significantly more patients with CFS who had never received influenza vaccine voiced this opinion than did patients who had received immunization for influenza in the past. Contrary to the opinions expressed by the sample, clinical trials in CFS have yet to find that any type of immunization has produced a deleterious effect on symptoms or functioning. Moreover, patients with CFS in a randomized, placebo-controlled, double-blind trial of influenza immunization produced an antibody titer in the protective range to inactivated trivalent influenza vaccine, although the geometric mean titer was slightly blunted compared with healthy vaccinees.

Although patients with CFS in placebo and active groups reported four times the number of post-injection adverse effects of healthy vaccinees, data re-analysis revealed that this finding was related to the overlap of common, post-influenza immunization symptoms and CFS constitutional symptoms. CFS is a poorly understood illness and some patients may believe in causal theories that lead to the rejection of disease prevention strategies such as immunization. However, influenza immunization appears to provide protective antibody levels without worsening CFS symptoms or causing excessive adverse effects. Efforts to motivate patients with CFS to obtain annual influenza immunization should take into account illness perceptions and concentrate on education based on placebo-controlled trials.

 

Source: Sleigh KM, Marra FH, Stiver HG. Influenza vaccination: is it appropriate in chronic fatigue syndrome? Am J Respir Med. 2002;1(1):3-9. http://www.ncbi.nlm.nih.gov/pubmed/14720070

 

Illness perceptions and levels of disability in patients with chronic fatigue syndrome and rheumatoid arthritis

Abstract:

OBJECTIVE: To investigate the strength of chronic fatigue syndrome (CFS) patients’ negative illness perceptions by comparing illness perceptions and self-reported disability in patients with CFS and rheumatoid arthritis (RA).

METHODS: Seventy-four RA patients and 49 CFS patients completed the Illness Perception Questionnaire-Revised and the 36-item Short-Form Health Survey.

RESULTS: When compared to the RA group, the CFS group attributed a wider range of everyday somatic symptoms to their illness, perceived the consequences of their illness to be more profound and were more likely to attribute their illness to a virus or immune system dysfunction. Both groups reported equivalent levels of physical disability but the CFS group reported significantly higher levels of role and social disability.

CONCLUSION: Although the symptoms of CFS are largely medically unexplained, CFS patients have more negative views about their symptoms and the impact that these have had on their lives than do patients with a clearly defined and potentially disabling medical condition. The data support the cognitive behavioural models of CFS that emphasise the importance of patients’ illness perceptions in perpetuating this disorder.

 

Source: Moss-Morris R, Chalder T. Illness perceptions and levels of disability in patients with chronic fatigue syndrome and rheumatoid arthritis. J Psychosom Res. 2003 Oct;55(4):305-8. http://www.ncbi.nlm.nih.gov/pubmed/14507540

 

Experimental evidence for interpretive but not attention biases towards somatic information in patients with chronic fatigue syndrome

Abstract:

OBJECTIVE: This study tested whether CFS patients have an attentional information processing bias for illness-related information and a tendency to interpret ambiguous information in a somatic fashion.

DESIGN: 25 patients meeting research criteria for a diagnosis of CFS were compared to 24 healthy matched controls on a modified Stroop task and an ambiguous cues task.

METHOD: In the modified Stroop task, participants colour named a series of somatic, depressed and neutral words in order to ascertain whether the somatic words were more distracting to the CFS patients than the depressed and neutral words when compared to controls. In the ambiguous cues task, participants were presented with a tape-recorded list of 30 words including 15 ambiguous illness words (e.g., vein/vain) and 15 unambiguous words. For each word, they were asked to write down the first word that came into their head. A somatic bias score was obtained for each subject by summing the number of somatic responses to the ambiguous word cues.

RESULTS: Although CFS patients were significantly slower in colour naming all of the Stroop word categories than controls, there was no evidence for illness or depressed words creating greater interference than neutral words. However, on the ambiguous cues task, CFS patients made significantly more somatic interpretations than controls and this bias was significantly associated with the extent to which they currently reported symptoms.

CONCLUSION: CFS patients have an interpretive bias for somatic information which may play a part in the maintenance of the disorder by heightening patients’ experience of physical symptoms and helping to maintain their negative illness schemas. Although patients did not show an attentional bias in this study, this may be related to the methodology employed.

 

Source: Moss-Morris R, Petrie KJ. Experimental evidence for interpretive but not attention biases towards somatic information in patients with chronic fatigue syndrome. Br J Health Psychol. 2003 May;8(Pt 2):195-208. http://www.ncbi.nlm.nih.gov/pubmed/12804333

 

Examining the influence of biological and psychological factors on cognitive performance in chronic fatigue syndrome: a randomized, double-blind, placebo-controlled, crossover study

Abstract:

The pathophysiology of chronic fatigue syndrome (CFS) remains unclear; however, both biological and psychological factors have been implicated in establishing or maintaining this condition. People with CFS report significant and disabling cognitive difficulties such as impaired concentration that in some cases are exacerbated by exposure to chemical triggers. The aim of this study was to determine if neuropsychological deficits in CFS are triggered by exposure to chemicals, or perceptions about the properties of these substances.

Participants were 36 people with a primary diagnosis of CFS, defined according to Centers for Disease Control (CDC) criteria. A randomized, double-blind, placebo-controlled, crossover design was used, with objective assessment of neuropsychological function and participant rating of substance type, before and after exposure to placebo or chemical trigger. Results showed decrements in neuropsychological tests scores on three out of four outcome measures when participants rated the substance they had been exposed to as “chemical.” No change in performance was found based on actual substance type.

These results suggest that cognitive attributions about exposure substances in people with CFS may be associated with worse performance on neuropsychological tasks. In addition, these findings suggest that psychological interventions aimed at modifying substance-related cognitions may reduce some symptoms of CFS.

 

Source: Smith S, Sullivan K. Examining the influence of biological and psychological factors on cognitive performance in chronic fatigue syndrome: a randomized, double-blind, placebo-controlled, crossover study. Int J Behav Med. 2003;10(2):162-73. http://www.ncbi.nlm.nih.gov/pubmed/12763708

 

A comparison of patients with chronic fatigue syndrome attending separate fatigue clinics based in immunology and psychiatry

Abstract:

Hospital clinics for patients with chronic unexplained fatigue are held in departments of various disciplines. This causes difficulties for referrers in choosing the appropriate clinic and for researchers in generalizing findings from one type of clinic to others.

We randomly selected 37 outpatients attending an immunology fatigue clinic and 36 outpatients attending a psychiatry fatigue clinic, all of whom had chronic fatigue syndrome. We compared demographic factors, symptoms, disability, quality of life, psychological distress and illness attributions.

The patients from the two clinics were closely similar in their specific symptoms, disability, quality of life, psychological distress and previous attendance to mental health professionals. Psychological distress was high and equal in the two samples. The proportion of men was greater among patients attending the immunology clinic. In a post-hoc analysis, 64% of immunology attenders attributed their fatigue to physical factors, compared with 31% of psychiatry clinic attenders (chi(2)=6.35, 1 d.f., P=0.01).

These findings suggest that research data from one type of chronic fatigue clinic can be generalized to others. Clinically similar patients are referred to different clinics, and the choice of clinic may be influenced by the patients’ illness beliefs. The high levels of emotional distress suggest that psychosocial management is as important as physical management in hospital outpatients with chronic fatigue syndrome, irrespective of its aetiology.

 

Source: White PD, Pinching AJ, Rakib A, Castle M, Hedge B, Priebe S. A comparison of patients with chronic fatigue syndrome attending separate fatigue clinics based in immunology and psychiatry. J R Soc Med. 2002 Sep;95(9):440-4. http://www.ncbi.nlm.nih.gov/pubmed/12205207

 

The role of fear of physical movement and activity in chronic fatigue syndrome

Abstract:

OBJECTIVE: To examine beliefs in relation to avoidance of activity in chronic fatigue syndrome (CFS) patients.

METHODS: The first phase consisted of modifying an existing chronic pain measure of kinesiophobia-fear of physical movement and activity-and validating it on the CFS population [Tampa Scale of Kinesiophobia-Fatigue (TSK-F); n=129; test-retest: r=.89, P<.001; alpha=.68]. Subscales of Illness Beliefs (alpha=.78) and Beliefs about Activity (alpha=.70) were identified. The second phase consisted of evaluating whether behavioural persistence was predicted by the TSK-F (n=33). Participants were asked to ride an exercise bike for as long as they felt able.

RESULTS: Analyses indicated that behavioural persistence did not correlate with maximal heart rate or resting heart rate, level of tiredness, symptom severity, illness identity or emotional distress. However, the TSK-F did correlate highly with distance travelled and added a significant 15% of the variance in distance after adjustments for gender and physical functioning (PF). The TSK-F Beliefs about Activity subscale appears to be the predictive factor, explaining 12% of the variance in excise performance or rather 12% of the avoidance of exercise.

CONCLUSION: Beliefs about Activity appear to be an important variable in predicting behaviour and avoidance of exercise. As avoidance has been suggested as a key to the maintenance of symptoms, disability and distress in CFS patients, this research has important theoretical, clinical and research implications.

 

Source: Silver A, Haeney M, Vijayadurai P, Wilks D, Pattrick M, Main CJ. The role of fear of physical movement and activity in chronic fatigue syndrome. J Psychosom Res. 2002 Jun;52(6):485-93. http://www.ncbi.nlm.nih.gov/pubmed/12069873

 

Toward a new definition of chronic fatigue syndrome

To the editor,

I agree with Lane when he writes that the operative criteria for diagnosing chronic fatigue syndrome (CFS) are unsatisfactory. Some patients who have been assigned this label may be better described as having depression or somatization, and this mislabeling prejudices the understanding of CFS in cross-sectional studies.1 Lane is presumably referring to the definition of the Centers for Disease Control and Prevention, with its concentration on physical symptoms.2 This definition also is not all that helpful in assigning a label to individuals for the purposes of estimating prognosis or deciding on treatment because the physical symptoms cited are nonspecific.

You can read the rest of this comment here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1071345/

 

Source: Robertson-Ritchie H. Toward a new definition of chronic fatigue syndrome. West J Med. 2001 Apr;174(4):241. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1071345/ (Full article)

 

Illness perceptions and mood in chronic fatigue syndrome

Abstract:

BACKGROUND: Individual beliefs and cognitions may affect adjustment to chronic fatigue syndrome (CFS) and illness perceptions, in particular, have been reported to correlate with both disability and psychological adjustment to CFS in self-diagnosed cases.

OBJECTIVES: The aim of the present study was to examine these relationships in a clinic sample of CFS patients assessed by both a physician and psychiatrist.

METHOD: A sample of 173 patients referred to a multidisciplinary CFS clinic and fulfilling current operational criteria for CFS [Ann Intern Med 121 (1994) 953; J R Soc Med 84 (1991) 118.] were randomly selected from the clinic database and surveyed with the Hospital Anxiety and Depression scale, Fatigue Questionnaire and Illness Perceptions Questionnaire [J Psychosom Res 37 (1993) 147; Psychol Health 11 (1996) 431; Acta Psychiatr Scand 67 (1983) 361.].

RESULTS: A total of 126 patients responded (73% response rate). The illness perception components studied were consequences (of illness), illness identity, causes (of illness), the ability to control/cure the illness and (expected) timeline of the illness. These components accounted for 15%, 28% and 30% of the variance in levels of fatigue, depression and anxiety, respectively. Two of the illness perception components (consequences and illness identity) were stronger predictors of fatigue score than mood scores.

CONCLUSIONS: These findings confirmed in a clinical sample that illness perceptions are associated with variation in both disability and psychological adjustment in CFS. Illness perceptions may have an important and long-lasting effect on adaptation to CFS, and it is necessary to have a greater understanding of their role in order to tailor effective interventions for the condition.

 

Source: Edwards R, Suresh R, Lynch S, Clarkson P, Stanley P. Illness perceptions and mood in chronic fatigue syndrome. J Psychosom Res. 2001 Feb;50(2):65-8. http://www.ncbi.nlm.nih.gov/pubmed/11274662

 

Chronic unexplained fatigue

Abstract:

Fatigue is a common symptom in the community and the commonest associations are with stress or mood disturbance. One in a hundred people complain of unexplained and prolonged fatigue, with half that number meeting the strictest criteria for the chronic fatigue syndrome (CFS). Discrete fatigue syndromes have been described, particularly after Epstein Barr virus infection. The majority of patients with CFS have a syndrome similar to the ICD-10 definition of neurasthenia. Mood and somatoform disorders are common comorbid or differential diagnoses. The prognosis is poor, particularly in patients attending hospitals and those with comorbid psychiatric disorders. The aetiology of both CFS and chronic unexplained fatigue are essentially unknown, perhaps reflecting the heterogenenous natures of both the symptom and syndrome. There is reasonable evidence to suggest that particular infections may trigger both prolonged fatigue and CFS. Maintaining factors are different from triggering factors and include mood and sleep disorders, illness beliefs and behaviours, and possibly inactivity. Treatments aimed at reversing these maintaining factors show promise.

 

Source: White PD. Chronic unexplained fatigue. Acta Neuropsychiatr. 1999 Dec;11(4):130-3. doi: 10.1017/S0924270800035870. http://www.ncbi.nlm.nih.gov/pubmed/26976541