Measuring the functional impact of fatigue: initial validation of the fatigue impact scale

Abstract:

The fatigue impact scale (FIS) was developed to improve our understanding of the effects of fatigue on quality of life. The FIS examines patients’ perceptions of the functional limitations that fatigue has caused over the past month. FIS items reflect perceived impact on cognitive, physical, and psychosocial functioning.

This study compared 145 patients referred for investigation of chronic fatigue (ChF) with 105 patients with multiple sclerosis (MS) and 34 patients with mild hypertension (HT). Internal consistency for the FIS and its three subscales was > .87 for all analyses. Fatigue impact was highest for the ChF group although the MS group’s reported fatigue also exceeded that of the HT group. Discriminant function analysis correctly classified 80.0% of the ChF group and 78.1% of the MS group when these groups were compared.

This initial validation study indicates that the FIS has considerable merit as a measure of patient’s attribution of functional limitations to symptoms of fatigue.

 

Source: Fisk JD, Ritvo PG, Ross L, Haase DA, Marrie TJ, Schlech. Measuring the functional impact of fatigue: initial validation of the fatigue impact scale. Clin Infect Dis. 1994 Jan;18 Suppl 1:S79-83. http://www.ncbi.nlm.nih.gov/pubmed/8148458

 

Sleep disorders in patients with chronic fatigue

Abstract:

This prospective, cohort study examined the prevalence of sleep disorders among highly selected patients with chronic fatigue. On the basis of responses suggestive of sleep pathology on a screening questionnaire, 59 patients from a university-based clinic for chronic fatigue who had undergone a medical and psychiatric evaluation underwent polysomnography.

Criteria for chronic fatigue syndrome (CFS) were met by 64% of patients and those for a current psychiatric disorder were met by 41%. Overall, 41% of patients had abnormal results for a multiple sleep latency test and 81% had at least one sleep disorder, most frequently sleep apnea (44%) and idiopathic hypersomnia (12%).

In comparing patients who did and did not meet CFS criteria, no significant differences were found in individual sleep symptoms or sleep disorders. Likewise, symptoms and sleep disorders were unrelated to psychiatric diagnoses. In conclusion, chronically fatigued patients with suggestive symptoms may have potentially treatable coexisting sleep disorders that are not associated with meeting criteria for CFS or a current psychiatric disorder.

 

Source: Buchwald D, Pascualy R, Bombardier C, Kith P. Clin Infect Dis. 1994 Jan;18 Suppl 1:S68-72. http://www.ncbi.nlm.nih.gov/pubmed/8148456

 

Acylcarnitine deficiency in chronic fatigue syndrome

Abstract:

One of the characteristic complaints of patients with chronic fatigue syndrome (CFS) is the skeletal muscle-related symptom. However, the abnormalities in the skeletal muscle that explain the symptom are not clear.

Herein, we show that our patients with CFS had a deficiency of serum acylcarnitine. As carnitine has an important role in energy production and modulation of the intramitochondrial coenzyme A (CoA)/acyl-CoA ratio in the skeletal muscle, this deficiency might induce an energy deficit and/or abnormality of the intramitochondrial condition in the skeletal muscle, thus resulting in general fatigue, myalgia, muscle weakness, and postexertional malaise in patients with CFS.

Furthermore, the concentration of serum acylcarnitine in patients with CFS tended to increase to the normal level with the recovery of general fatigue. Therefore, the measurement of acylcarnitine would be a useful tool for the diagnosis and assessment of the degree of clinical manifestation in patients with CFS.

 

Source: Kuratsune H, Yamaguti K, Takahashi M, Misaki H, Tagawa S, Kitani T. Acylcarnitine deficiency in chronic fatigue syndrome. Clin Infect Dis. 1994 Jan;18 Suppl 1:S62-7. http://www.ncbi.nlm.nih.gov/pubmed/8148455

 

Hyperventilation and chronic fatigue syndrome

Abstract:

We studied the link between chronic fatigue syndrome (CFS) and hyperventilation in 31 consecutive attenders at a chronic fatigue clinic (19 females, 12 males) who fulfilled criteria for CFS based on both Oxford and Joint CDC/NIH criteria. All experienced profound fatigue and fatigability associated with minimal exertion, in 66% developing after an infective episode. Alternative causes of fatigue were excluded.

Hyperventilation was studied during a 43-min protocol in which end-tidal PCO2 (PETCO2) was measured non-invasively by capnograph or mass spectrometer via a fine catheter taped in a nostril at rest, during and after exercise (10-50 W) and for 10 min during recovery from voluntary overbreathing to approximately 2.7 kPa (20 mmHg). PETCO2 < 4 kPa (30 mmHg) at rest, during or after exercise, or at 5 min after the end of voluntary overbreathing, suggested either hyperventilation or a tendency to hyperventilate. Most patients were able voluntarily to overbreathe, but not all were able to exercise.

Twenty-two patients (71%) had no evidence of hyperventilation during any aspect of the test. Only four patients had unequivocal hyperventilation, in one associated with asthma and in three with panic. Only one patient with severe functional disability and agoraphobia had hyperventilation with no other obvious cause. A further five patients had borderline hyperventilation, in which PETCO2 was < 4 kPa (30 mmHg) for no more than 2 min, when we would have expected it to be normal. There was no association between level of functional impairment and degree of hyperventilation. There is only a weak association between hyperventilation and chronic fatigue syndrome.(ABSTRACT TRUNCATED AT 250 WORDS)

Comment in: Hyperventilation and the chronic fatigue syndrome. [Q J Med. 1994]

Source: Saisch SG, Deale A, Gardner WN, Wessely S. Hyperventilation and chronic fatigue syndrome. Q J Med. 1994 Jan;87(1):63-7. http://www.ncbi.nlm.nih.gov/pubmed/8140219

 

Seasonal symptom variation in patients with chronic fatigue: comparison with major mood disorders

Abstract:

The psychobiology of idiopathic fatigue has received renewed interest in the medical literature in recent years. In order to examine the relation between chronic, idiopathic fatigue and specific subtypes of depressive illness, we characterized the pattern and severity of seasonal symptom variation in 73 patients with chronic, idiopathic fatigue, compared to patients with major depression (n = 55), atypical depression (n = 35), and seasonal affective disorder (n = 16) Fifty of the fatigued subjects also met the specific Centers for Disease Control and Prevention case criteria for chronic fatigue syndrome, though this definition was unable to discriminate a distinct subgroup of patients, based on their seasonality scores alone. As a group, the fatigued subjects reported the lowest levels of symptom seasonality of any of the study groups. Further, even in those fatigued subjects with scores in the range of those seen in patients with seasonal affective disorder, seasonality was not reported to be a subjectively distressing problem. These findings lend support to the idea that although chronic fatigue shares some clinical features with certain mood disorders, they are not the same illnesses. These data are also consistent with the emerging view that chronic fatigue represents a heterogeneously determined clinical condition.

 

Source: Zubieta JK, Engleberg NC, Yargiç LI, Pande AC, Demitrack MA. Seasonal symptom variation in patients with chronic fatigue: comparison with major mood disorders. J Psychiatr Res. 1994 Jan-Feb;28(1):13-22. http://www.ncbi.nlm.nih.gov/pubmed/8064638

 

The chronic fatigue syndrome

Abstract:

CFIDS (chronic fatigue and immune disfunction syndrome) is also known as CFS (chronic fatigue syndrome), CEBV (chronic Epstein-Barr virus), M.E. (myalgic encephalomyelitis), yuppie flu and by other names.

It is a complex illness characterized by incapacitating fatigue (experienced as exhaustion and extremely poor stamina), neurological problems and a constellation of symptoms that can resemble many disorders, including; mononucleosis, multiple sclerosis, fibromyalgia, AIDS-related complex (ARC) and autoimmune diseases such as lupus. These symptoms tend to wax and wane, but any often severely debilitating and may last for many months or years. All sections of the population (including children) are at risk, but women under 45 seem to be most susceptible.

The investigators suggest that CFIDS results from dysfunction of the immune system. The exact nature of this dysfunction is not yet well defined, but it can generally be viewed as an unregulated or overactive state which is responsible for most of the symptoms. There is also evidence of some immune suppression in CFIDS. None of the treatments is consistently satisfactory, but some may be helpful: psychotherapy, physiotherapy, exercise programs, acupunctures, small doses of antidepressants, etc.

 

Source: Artsimovich NG, Chugunov VS, Kornev AV, Ivanova TM, Chugunov AV, Oprishchenko MA. The chronic fatigue syndrome. Zh Nevrol Psikhiatr Im S S Korsakova. 1994;94(5):47-50. [Article in Russian] http://www.ncbi.nlm.nih.gov/pubmed/7900453

 

Chronic fatigue syndrome: immune dysfunction, role of pathogens and toxic agents and neurological and cardial changes

Abstract:

375 patients with chronic fatigue syndrome (CFS) were examined using a standardized questionnaire and subsequent interview on 11 risk factors and 45 symptoms. Additionally immunologic, serologic, toxicologic, neuroradiologic, neurophysiologic and cardiologic investigations were performed.

Immunologic tests showed cellular immunodeficiences particularly in functional regard (pathological lymphocyte stimulation in 50% of the patients, disorders of granulocyte function in 44%). Furthermore variable deviations were found in the lymphocyte subpopulations (CD3, CD4, CD8, CD19, DR, Leu 11 + 19).

In the humoral part tendencies to low IgG-3- and IgG-1-subclass-levels occurred (59% respectively 11% of the patients) also as decreases in complement system (CH50, C3, C4, C1-esterase-inhibitor). In the group of activation markers and cytokines 42% of the investigated patients had circulating immune complexes (CIC), 47% increases of tumor-necrosis-factor (TNF-a) and 21% increases of soluble interleukin-2-receptor (IL-2-R).

The increased occurrence of autoantibodies in the CFS-patients (specially antinuclear anti-bodies [ANA], microsomal thyroid antibodies) suggest, that CFS is associated with or the beginning of manifest autoimmune disease.

Under the pathogens 78% of the patients had a striking serological constellation of Epstein-Barr-Virus (EBV-EA positive, low EBNA-titers), in the HHV-6-Virus 47% showed increased antibody-titers. Tests on further herpes viruses and on Borreliae, Chlamydiae, Candida and Amoebae were positive in 8 to 36% of the examined patients. Furthermore there were found variable deficits of vitamins and trace elements also as hormonal disturbances.

In 26% of the patients there were hints of pollutants (e.g. wood preservatives), in 32 patients blood-levels of pentachlorphenol (PCP) and gamma-hexachlorcyclohexan (γ-HCH, lindan) were measured, which showed vanable increases.

178 (83%) of 225 investigated patients showed disturbances of perfusion in cerebral SPECT imaging, 65 (29%) of 218 patients cerebral punctuate signal changes in cranial magnetic resonance imaging (MRI).

Neurophysiologic measurements (motor evoked potentials, MEP) showed in about 50% of 112 patients prolonged central motor conduction times. 62 patients were additionally investigated by myocardial SPECT-imaging, which was abnormal under exercise in 73%. Our data confirm the concept, that CFS must be considered as a complex psycho-neuro-immunological disorder.

 

Source: Hilgers A, Frank J. Chronic fatigue syndrome: immune dysfunction, role of pathogens and toxic agents and neurological and cardial changes. Wien Med Wochenschr. 1994;144(16):399-406.[Article in German] http://www.scopus.com/record/display.uri?eid=2-s2.0-0027940724&origin=inward&txGid=0

and http://www.ncbi.nlm.nih.gov/pubmed/7856214

 

 

Insomnia in the chronic fatigue syndrome

Editor,-Iain Duncan is mistaken in his assertion that the results of our study of patients with the chronic fatigue syndrome can be explained by daytime dozing. According to data from the diaries kept by the subjects in the study, the patients with the chronic fatigue syndrome slept for a mean of 11 minutes during the day and the healthy controls for 0 minutes. There was no association between either the time spent asleep or the time spent resting in bed during the day and the presence of any sleep disorder (or the time spent awake after the onset of sleep at night) in the patients with the chronic fatigue syndrome or the normal controls. Furthermore, in the few patients with the syndrome who wore their polysomnograph for the whole 24 hours there was no association between time spent asleep during the day and the time spent awake after the onset of sleep.

You can read the rest of this comment here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1678179/pdf/bmj00031-0056a.pdf

 

Source: Morriss R. Insomnia in the chronic fatigue syndrome. BMJ. 1993 Jul 24;307(6898):264. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1678179/

 

ABC of sleep disorders. Sleep problems in patients with medical illness

Sleep complaints are ubiquitous in patients with medical illness. A recent survey of outpatients attending hospital clinics indicated that the vast majority of patients reported sleep disruption concomitant with their condition. The proportion with complaints (> 70%) was more than twice that among control subjects. Doctors rarely ask about sleep problems in the context of medical illness despite the fact that the patient’s first complaint disruption of sleep architecture in may be that a particular symptom caused sleep disruption.

There are specific reasons for sleep disruptions in patients with medical illness-for example, people are often deprived of sleep before an operation. Polysomnography has shown that there is a preoperative of sleep) reduction in slow wave sleep and that this is related to the anticipated importance of surgery. The increase in deep sleep that occurs after an operation is thought to facilitate the healing process.

A variety of sleep variables may be influenced by specific disorders and each of these effects is likely to differ. A decrease in deep (slow wave) sleep, for example, may lead to a sensation of having low energy, whereas repeated interruption of sleep may lead to daytime sleepiness.

Drugs may also disrupt sleep architecture by suppressing rapid eye movement (REM) sleep or by causing a withdrawal effect during the night. In both cases the drug clearly alters sleep, but the impact on health and recovery may differ.

Fatigue is common in several medical conditions. Clinicians, researchers, and patients themselves claim that the fatigue experienced in certain medical conditions differs qualitatively from the experience of tiredness or sleepiness. However, there have been few attempts to separate these states. In this article we provide an overview of the impact of medical disorders on sleep.

You can read the rest of this article here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1677972/pdf/bmj00023-0050.pdf

 

Source: Shapiro CM, Devins GM, Hussain MR. ABC of sleep disorders. Sleep problems in patients with medical illness. BMJ. 1993 Jun 5;306(6891):1532-5. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1677972/

 

Sleep disturbance in chronic fatigue syndrome

Abstract:

Sleep and fatigue characteristics were evaluated in 72 patients who met major criteria for the chronic fatigue syndrome (CFS), 57 multiple sclerosis (MS) patients preselected for fatigue complaints, and 40 healthy controls.

Using previously validated rating scales, CFS patients had significant elevations in fatigue and sleep disturbance compared to the MS and healthy control groups. To confirm these subjective measures, polysomnography was carried out in a subgroup of CFS patients who included sleep disturbance as one of their symptoms on initial clinical interview.

In 10 of 16 (62.5%) polysomnography revealed clinically significant and potentially treatable sleep abnormalities. Their sleep disorders included periodic movement disorder (4), excessive daytime sleepiness (3), apnea (2), and narcolepsy (1).

We conclude that subjective sleep disturbance is common in CFS and some CFS patients may have objective sleep disorders.

 

Source: Krupp LB, Jandorf L, Coyle PK, Mendelson WB. Sleep disturbance in chronic fatigue syndrome. J Psychosom Res. 1993 May;37(4):325-31. http://www.ncbi.nlm.nih.gov/pubmed/8510058