Multiple chemical sensitivity disorder in patients with neurotoxic illnesses

Abstract:

The data of 466 subjects suffering from neurologic disorders which are suggested to be caused by neurotoxic agents in their environment retrospectively was evaluated and documented. Among these cases there were 151 subjects with symptoms of Multiple Chemical Sensitivity Disorder (MCSD). The relationship between the neurological health impairments and neurotoxic agents in the environment of these patients was characterised using five different categories (probable = A, possible = B, uncertain = C, unclarified = D, not probable = E). From the 466 patients 320 subjects (69%) could be assigned to the categories A and B, respectively.

Within theses 320 cases with chronic neurotoxic health impairments 136 subjects (79 females and 57 males) showed signs of MCSD. Age and gender of cases as well as duration and character of exposure to neurotoxic substances retrospectively were assessed from the explicit files of the patients, which had been made anonymous for this purpose. Frequency of characteristic symptoms of neurotoxicity were analysed. Results are given for patients with neurotoxic health impairments with MCSD (n = 136) and without MCSD (n = 184).

Neurotoxic substances which were used as indoor wood preservatives (mainly Pentachlorophenol and/or Lindane) were found to be the causative agents in 63% of the cases with neurotoxic health impairments and MCSD. Other important neurotoxic substances to which the patients were mainly exposed were organic solvents (25%), formaldehyde (15%), dental materials (15%), pyrethroides (13%), and other biocides (19%) (multiple exposures were possible). The time of exposure was calculated as being > or = 10 years for 55% of the patients with MCSD and for 50% of the group with neurotoxic health impairments but without MCSD.

Out of the 184 cases with neurotoxic health impairments but without MCSD there were 22%, and out of the 136 cases with MCSD there were 39% who showed all symptoms of chronic fatigue syndrome. 53% of the cases with MCSD had an allergic disposition compared to only 20% of the cases without MCSD.

This work is not a controlled epidemiological study but a retrospective documentation and evaluation of data related to environmental medicine. With the present documentation in this purely descriptive manner the proof of a causal relationship was not possible or intended. But because corresponding epidemiological studies are lacking, this documentation can give important information on characteristic features of Multiple Chemical Sensitivity Disorder and chronic neurotoxic health impairments. Such information is essential for planning and carrying out epidemiological studies urgently needed in this field.

Comment in:

Comment on K. Lohmann, Anke Pröhl, E. Schwarz. Multiple chemical sensitivity in patients with neurotoxic illnesses. Gesundheitswesen. 1997 [Article in German]

 

Source: Lohmann K, Pröhl A, Schwarz E. Multiple chemical sensitivity disorder in patients with neurotoxic illnesses. Gesundheitswesen. 1996 Jun;58(6):322-31. [Article in German] http://www.ncbi.nlm.nih.gov/pubmed/8766847

 

Metabolic and cardiovascular effects of a progressive exercise test in patients with chronic fatigue syndrome

Abstract:

PURPOSE: To evaluate the aerobic power (as maximum volume of oxygen consumed [VO2 max]) of women with chronic fatigue syndrome (CFS).

PATIENTS AND METHODS: Twenty-one women with CFS and 22 sedentary healthy controls (CON) were studied at the CFS Cooperative Research Center Exercise Laboratory at the VA Medical Center, East Orange, New Jersey. Performance was measured on an incremental treadmill protocol walking to exhaustion. Expired gases were analyzed by a metabolic system, heart rate was recorded continuously, and ratings of perceived exertion (RPE) were taken at each workload. The groups were divided into those who achieved VO2 max (CFS-MAX and CON-MAX) and those who stopped at a submaximal level (CFS-NOMAX and CON-NOMAX) by using standard criteria.

RESULTS: Seventeen CON and 10 CFS subjects achieved VO2 max. The VO2 max (mL/kg/min) of the CFS-MAX (28.1 +/- 5.1) was lower than that of the CON-MAX (32.1 +/- 4.3, P = 0.05). The CFS-MAX achieved 98 +/- 11% of predicted VO2 max. The CFS group had a higher RPE at the same absolute workloads as controls (P < 0.01) but not the same relative workloads.

CONCLUSION: Compared with normal controls, women with CFS have an aerobic power indicating a low normal fitness level with no indication of cardiopulmonary abnormality. Our CFS group could withstand a maximal treadmill exercise test without a major exacerbation in either fatigue or other symptoms of their illness.

Comment in:

Exercise limits in chronic fatigue syndrome. [Am J Med. 1997]

Graded exercise testing and chronic fatigue syndrome. [Am J Med. 1997]

 

Source: Sisto SA, LaManca J, Cordero DL, Bergen MT, Ellis SP, Drastal S, Boda WL, Tapp WN, Natelson BH. Metabolic and cardiovascular effects of a progressive exercise test in patients with chronic fatigue syndrome. Am J Med. 1996 Jun;100(6):634-40. http://www.ncbi.nlm.nih.gov/pubmed/8678084

 

A national assessment of the service, support, and housing preferences by persons with chronic fatigue syndrome. Toward a comprehensive rehabilitation program

Abstract:

Persons with Chronic Fatigue Syndrome (PWCs) completed and returned by mail a brief survey of open- and closed-ended items designed to assess their utilization and preferences for a variety of services. A total of 984 middle-aged adults diagnosed with Chronic Fatique Syndrome (CFS) from across North America returned the survey. During the past 12 months, many of these PWCs reported utilization of a primary care physician, gynecologist, CFS specialist, and self-help group to assist in their recovery from CFS. Most PWCs believed it was important to educate both health-care practitioners and the general public about CFS. In terms of their desire for specific recovery needs, factor analysis of responses indicated that these PWCs preferred self-help/social support services and general advocacy services in the treatment of their illness. The implications of these results for developing rehabilitation programs for PWCs are discussed.

 

Source: Jason LA, Ferrari JR, Taylor RR, Slavich SP, Stenzel CL. A national assessment of the service, support, and housing preferences by persons with chronic fatigue syndrome. Toward a comprehensive rehabilitation program. Eval Health Prof. 1996 Jun;19(2):194-207. http://www.ncbi.nlm.nih.gov/pubmed/10186910

 

Fibromyalgia and chronic fatigue syndrome: similarities and differences

Abstract:

CFS and FM are clinical conditions characterized by a variety of nonspecific symptoms including prominent fatigue, myalgia, and sleep disturbances. There are no diagnostic studies or widely accepted, pathogenic, explanatory models for either illness. Despite remarkably different diagnostic criteria, CFS and FM have many demographic and clinical similarities. More specifically, few differences exist in the domains of symptoms, examination findings, laboratory tests, functional status, psychosocial features, and psychiatric disorders. FM appears to represent an additional burden of suffering among those with CFS, however, underscoring the importance of recognizing concurrent CFS and FM. Further clarification of the similarities (and differences) between CFS and FM may be useful in studies of prognosis and help define subsets of patients who may benefit from specific therapeutic interventions.

 

Source: Buchwald D. Fibromyalgia and chronic fatigue syndrome: similarities and differences. Rheum Dis Clin North Am. 1996 May;22(2):219-43. http://www.ncbi.nlm.nih.gov/pubmed/9157484

 

Evidence that abnormalities of central neurohormonal systems are key to understanding fibromyalgia and chronic fatigue syndrome

Abstract:

Fibromyalgia (FM) and chronic fatigue syndrome (CFS) fall into the spectrum of what might be termed stress-associated syndromes by virtue of frequent onset after acute or chronic stressors and apparent exacerbation of symptoms during periods of physical or emotional stress. These illnesses also share perturbation of the hypothalamic-pituitary-adrenal axis and sympathetic stress response systems. In this article, the authors discuss the specific neurohormonal abnormalities found in FM and CFS and potential mechanisms by which dysfunction of neurohormonal stress-response systems could contribute to vulnerability to stress-associated syndromes and to the symptoms of FM and CFS.

 

Source: Crofford LJ, Demitrack MA. Evidence that abnormalities of central neurohormonal systems are key to understanding fibromyalgia and chronic fatigue syndrome. Rheum Dis Clin North Am. 1996 May;22(2):267-84. http://www.ncbi.nlm.nih.gov/pubmed/8860799

 

Chronic fatigue and minor psychiatric morbidity after viral meningitis: a controlled study

Abstract:

OBJECTIVE: To test the hypotheses that patients exposed to viral meningitis would be at an increased risk of developing chronic fatigue syndrome and would have an excess of neurological symptoms and physical impairment.

METHODS: Eighty three patients were followed up 6-24 months after viral meningitis and a postal questionnaire was used to compare outcome with 76 controls who had had non-enteroviral, non-CNS viral infections.

RESULTS: For the 159 patients and controls the prevalence of chronic fatigue syndrome was 12.6%, a rate higher than previously reported from primary care attenders, suggesting that moderate to severe viral infections may play a part in the aetiology of some fatigue states. Those with a history of meningitis showed a slight, non-significant increase in prevalence of chronic fatigue syndrome (OR 1.4; 95% CI 0.5-3.6) which disappeared when logistic regression and analysis was used to correct for age, sex, and duration of follow up (OR 1.0; 95% CI 0.3-2.8). Controls showed marginally higher psychiatric morbidity measured on the general health questionnaire-12 (adjusted OR 0.6; 95% CI 0.3-1.3) Both groups had similar rates of neurological symptoms and physical impairment. The best predictor of chronic fatigue was a prolonged duration time of off work after the illness (OR 4.93, 95% CI 1.3-18.8). The best predictor of severe chronic fatigue syndrome diagnosed by Center for Disease Control criteria was past psychiatric illness (OR 7.82, 95% CI 1.8-34.3). Duration of viral illness, as defined by days in hospital, did not predict chronic fatigue syndrome.

CONCLUSIONS: (1) The prevalence of chronic fatigue syndrome is higher than expected for the range of viral illnesses examined; (2) enteroviral infection is unlikely to be a specific risk factor for its development; (3) onset of chronic fatigue syndrome after a viral infection is predicted by psychiatric morbidity and prolonged convalescence, rather than by the severity of the viral illness itself.

 

Source: Hotopf M, Noah N, Wessely S. Chronic fatigue and minor psychiatric morbidity after viral meningitis: a controlled study. J Neurol Neurosurg Psychiatry. 1996 May;60(5):504-9. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC486361/ (Full article)

 

Memory, attention, and executive function in chronic fatigue syndrome

Abstract:

OBJECTIVES: To examine cognitive function in chronic fatigue syndrome.

METHODS: Twenty patients with chronic fatigue syndrome recruited from primary care and 20 matched normal controls were given CANTAB computerised tests of visuospatial memory, attention, and executive function, and verbal tests of letter and category fluency and word association learning.

RESULTS: Patients with chronic fatigue syndrome were impaired, predominantly in the domain of memory but their pattern of performance was unlike that of patients with amnesic syndrome or dementia. They were normal on tests of spatial pattern recognition memory, simultaneous and delayed matching to sample, and pattern-location association learning. They were impaired on tests of spatial span, spatial working memory, and a selective reminding condition of the pattern-location association learning test. An executive test of planning was normal. In an attentional test, eight subjects with chronic fatigue syndrome were unable to learn a response set; the remainder exhibited no impairment in the executive set shifting phase of the test. Patients with chronic fatigue syndrome were also impaired on verbal tests of unrelated word association learning and letter fluency.

CONCLUSION: Patients with chronic fatigue syndrome have reduced attentional capacity resulting in impaired performance on effortful tasks requiring planned or self ordered generation of responses from memory.

Source: Joyce E, Blumenthal S, Wessely S. Memory, attention, and executive function in chronic fatigue syndrome. J Neurol Neurosurg Psychiatry. 1996 May;60(5):495-503. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC486360/ (Full article)

Prognosis in chronic fatigue syndrome: a prospective study on the natural course

Abstract:

OBJECTIVE: To determine spontaneous improvement after a follow up interval of 18 months in patients with chronic fatigue syndrome and to identify factors that predict improvement.

METHODS: A longitudinal study was used. Of 298 initially assessed self referred patients fulfilling criteria for chronic fatigue syndrome, 246 patients completed self report questionnaires at follow up (response rate 83%). A multidimensional assessment method was used, measuring behavioural, emotional, cognitive, and social functioning. Comparison data from 53 healthy subjects matched for age, sex, and educational level were available.

RESULTS: Three per cent of patients reported complete recovery and 17% reported improvement. At follow up, there were considerable problems at work and consumption of medication was high. Subjective improvement was confirmed by dimensional change: at follow up recovered patients had similar scores to healthy subjects and improved patients showed significant improvement on four out of seven outcome measures and had higher scores than healthy subjects in all dimensions. Sociodemographic variables or treatment by specialists and alternative practitioners did not predict improvement. Predictors of improvement were: subjective sense of control over symptoms, less fatigue, shorter duration of complaints, and a relative absence of physical attributions.

CONCLUSION: The improvement rate in patients with a relatively long duration of complaints is small. Psychological factors are related to improvement, especially cognitive factors.

 

Source: Vercoulen JH, Swanink CM, Fennis JF, Galama JM, van der Meer JW, Bleijenberg G. Prognosis in chronic fatigue syndrome: a prospective study on the natural course. J Neurol Neurosurg Psychiatry. 1996 May;60(5):489-94. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC486359/ (Full article)

Neuropsychological deficits in chronic fatigue syndrome: artifact or reality?

Chronic fatigue syndrome is an illness characterised by extreme fatigue of uncertain origin which has been present for at least six months. The fatigue should have a sudden onset and be severe enough to substantially reduce the patient’s day to day activities. A number of other symptoms are associated with chronic fatigue syndrome including complaints of impaired memory, difficulty making decisions, poor attention, and reduced concentration. Many patients complain that it is these cognitive symptoms which cause them the greatest frustration and disability.

You can read the rest of this article here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC486357/pdf/jnnpsyc00017-0004.pdf

 

Source: Moss-Morris R, Petrie KJ, Large RG, Kydd RR. Neuropsychological deficits in chronic fatigue syndrome: artifact or reality? J Neurol Neurosurg Psychiatry. 1996 May;60(5):474-7. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC486357/

 

Neuroimaging in chronic fatigue syndrome

The link between viral infection, the brain, and fatiguing illnesses has a long history. This combination forced itself on the medical imagination after events in Austria in the winter of 1916-17. A virulent form of influenza was noted, characteristically, to produce lethargy and later, to leave a host of neurological deficits in its wake. By the spring of 1918 several English cases of encephalitis lethargica had been reported and in the next year the disease was notifiable. The peak of the epidemic occurred in 1924 in the United Kingdom, at which time the Board of Control reported that many cases had been admitted to hospital with psychiatric disturbances.1 Hence the notion that apparent psychiatric illnesses may be misdiagnosed manifestations of a postinfectious cerebral disease began; it refuses to disappear.23

You can read the rest of this article here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC486356/pdf/jnnpsyc00017-0001.pdf

 

Source: Cope H, David AS. Neuroimaging in chronic fatigue syndrome. J Neurol Neurosurg Psychiatry. 1996 May;60(5):471-3. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC486356/