Tag: Straus

Attention and short-term memory in chronic fatigue syndrome patients: an event-related potential analysis

Abstract:

We recorded event-related brain potentials (ERPs) from 13 patients with chronic fatigue syndrome (CFS) and 13 matched normal controls. To assess attentional and memory deficits in CFS patients, we used a short-term memory task in which events occurred in different spatial locations and the patients made a rapid-response (RT) when a letter in a relevant location matched a letter in the prememorized set (Attention paradigm).

Time-on-task effects on the ERP and behavioral measures were assessed over the 2 1/4-hour duration of this task. Both groups also performed a visual Oddball paradigm, with an RT, before and after the Attention paradigm. The patients’ RTs were much more variable and, in nine of 13 cases, slower than the mean RT of the controls in both paradigms.

The patients’ memory performance was not significantly different from that of the controls and there were no group differences in the overall amplitude, latency, or scalp distribution of the N1, P2, N2, or P300 components of the ERP in either paradigm. The ERP and performance data from both paradigms suggest that perceptual, attentional, and short-term memory processes were unaffected in CFS patients and that the differences were limited to response-related processes.

 

Source: Scheffers MK, Johnson R Jr, Grafman J, Dale JK, Straus SE. Attention and short-term memory in chronic fatigue syndrome patients: an event-related potential analysis. Neurology. 1992 Sep;42(9):1667-75. http://www.ncbi.nlm.nih.gov/pubmed/1513453

 

NIH conference. Chronic fatigue syndrome research. Definition and medical outcome assessment

Abstract:

A workshop was held 18 to 19 March 1991 at the National Institutes of Health to address critical issues in research concerning the chronic fatigue syndrome (CFS). Case definition, confounding diagnoses, and medical outcome assessment by laboratory and other means were considered from the perspectives of key medical specialties involved in CFS research.

It was recommended that published Centers for Disease Control (CDC) case-definition criteria be modified to exclude fewer patients from analysis because of a history of psychiatric disorder. Specific recommendations were made concerning the inclusion or exclusion of other major confounding diagnoses, and a standard panel of laboratory tests was specified for initial patient evaluation.

The workshop emphasized the importance of recognizing other conditions that could explain the patient’s symptoms and that may be treatable. It was viewed as essential for the investigator to screen for psychiatric disorder using a combination of self-report instruments followed by at least one structured interview to identify patients who should be excluded from studies or considered as a separate subgroup in data analysis.

Because CFS is not a homogeneous abnormality and because there is no single pathogenic mechanism, research progress may depend upon delineation of these and other patient subgroups for separate data analysis. Despite preliminary data, no physical finding or laboratory test was deemed confirmatory of the diagnosis of CFS.

For assessment of clinical status, investigators must rely on the use of standardized instruments for patient self-reporting of fatigue, mood disturbance, functional status, sleep disorder, global well-being, and pain. Further research is needed to develop better instruments for quantifying these domains in patients with CFS.

 

Source: Schluederberg A, Straus SE, Peterson P, Blumenthal S, Komaroff AL, Spring SB, Landay A, Buchwald D. NIH conference. Chronic fatigue syndrome research. Definition and medical outcome assessment. Ann Intern Med. 1992 Aug 15;117(4):325-31. http://www.ncbi.nlm.nih.gov/pubmed/1322076

 

Evidence for impaired activation of the hypothalamic-pituitary-adrenal axis in patients with chronic fatigue syndrome

Abstract:

Chronic fatigue syndrome is characterized by persistent or relapsing debilitating fatigue for at least 6 months in the absence of a medical diagnosis that would explain the clinical presentation. Because primary glucocorticoid deficiency states and affective disorders putatively associated with a deficiency of the arousal-producing neuropeptide CRH can be associated with similar symptoms, we report here a study of the functional integrity of the various components of the hypothalamic-pituitary-adrenal axis in patients meeting research case criteria for chronic fatigue syndrome.

Thirty patients and 72 normal volunteers were studied. Basal activity of the hypothalamic-pituitary-adrenal axis was estimated by determinations of 24-h urinary free cortisol-excretion, evening basal plasma total and free cortisol concentrations, and the cortisol binding globulin-binding capacity. The adrenal cortex was evaluated indirectly by cortisol responses during ovine CRH (oCRH) stimulation testing and directly by cortisol responses to graded submaximal doses of ACTH. Plasma ACTH and cortisol responses to oCRH were employed as a direct measure of the functional integrity of the pituitary corticotroph cell. Central CRH secretion was assessed by measuring its level in cerebrospinal fluid.

Compared to normal subjects, patients demonstrated significantly reduced basal evening glucocorticoid levels (89.0 +/- 8.7 vs. 148.4 +/- 20.3 nmol/L; P less than 0.01) and low 24-h urinary free cortisol excretion (122.7 +/- 8.9 vs. 203.1 +/- 10.7 nmol/24 h; P less than 0.0002), but elevated basal evening ACTH concentrations.

There was increased adrenocortical sensitivity to ACTH, but a reduced maximal response [F(3.26, 65.16) = 5.50; P = 0.0015). Patients showed attenuated net integrated ACTH responses to oCRH (128.0 +/- 26.4 vs. 225.4 +/- 34.5 pmol/L.min, P less than 0.04). Cerebrospinal fluid CRH levels in patients were no different from control values (8.4 +/- 0.6 vs. 7.7 +/- 0.5 pmol/L; P = NS).

Although we cannot definitively account for the etiology of the mild glucocorticoid deficiency seen in chronic fatigue syndrome patients, the enhanced adrenocortical sensitivity to exogenous ACTH and blunted ACTH responses to oCRH are incompatible with a primary adrenal insufficiency. A pituitary source is also unlikely, since basal evening plasma ACTH concentrations were elevated.

Hence, the data are most compatible with a mild central adrenal insufficiency secondary to either a deficiency of CRH or some other central stimulus to the pituitary-adrenal axis. Whether a mild glucocorticoid deficiency or a putative deficiency of an arousal-producing neuropeptide such as CRH is related to the clinical symptomatology of the chronic fatigue syndrome remains to be determined.

 

Source: Demitrack MA, Dale JK, Straus SE, Laue L, Listwak SJ, Kruesi MJ, Chrousos GP, Gold PW. Evidence for impaired activation of the hypothalamic-pituitary-adrenal axis in patients with chronic fatigue syndrome. J Clin Endocrinol Metab. 1991 Dec;73(6):1224-34. http://www.ncbi.nlm.nih.gov/pubmed/1659582

 

Chronic fatigue syndrome: lack of association with hepatitis C virus infection

Abstract:

Chronic fatigue syndrome (CFS) is a debilitating heterogeneous disorder lacking consistent, objective physical or laboratory abnormalities. Among the hypothetical etiologies for CFS are chronic viral infections. The present controlled seroprevalence study found that, among typical CFS patients, evidence of hepatitis C virus (HCV) infection is uncommon. Only one of 36 patients and none of 14 controls were anti-HCV positive. The positive patient had persistent aminotransferase elevations and prior posttransfusion hepatitis. Thus HCV infection is not a common feature of CFS and should not be routinely sought.

 

Source: Dale JK, Di Bisceglie AM, Hoofnagle JH, Straus SE. Chronic fatigue syndrome: lack of association with hepatitis C virus infection. J Med Virol. 1991 Jun;34(2):119-21. http://www.ncbi.nlm.nih.gov/pubmed/1653818

 

Psychiatric diagnoses in patients who have chronic fatigue syndrome

Abstract:

Patients with persistent fatigue are often suspected of having psychiatric illnesses, particularly depression. The authors used the Diagnostic Interview Schedule to assess the lifetime prevalence of psychiatric disorders in 28 patients who met Centers for Disease Control case definition criteria for chronic fatigue syndrome. Compared with studies of the general population and studies of chronically medically ill patients who received the same structured interview, the rates of psychiatric illness in patients with the chronic fatigue syndrome appeared high. An examination of the medical histories of the 28 patients indicated that psychiatric disorders more often preceded the chronic fatigue than followed it.

 

Source: Kruesi MJ, Dale J, Straus SE. Psychiatric diagnoses in patients who have chronic fatigue syndrome. J Clin Psychiatry. 1989 Feb;50(2):53-6.  http://www.ncbi.nlm.nih.gov/pubmed/2536690

 

Acyclovir treatment of the chronic fatigue syndrome. Lack of efficacy in a placebo-controlled trial

Abstract:

Twenty-seven adults with a diagnosis of the chronic fatigue syndrome were enrolled in a double-blind, placebo-controlled study of acyclovir therapy. The patients had had debilitating fatigue for an average of 6.8 years, accompanied by persisting antibodies to Epstein-Barr virus early antigens (titers greater than or equal to 1:40) or undetectable levels of antibodies to Epstein-Barr virus nuclear antigens (titers less than 1:2) or both.

Each course of treatment consisted of intravenous placebo or acyclovir (500 mg per square meter of body-surface area) administered every eight hours for seven days. The same drug was then given orally for 30 days (acyclovir, 800 mg four times daily). There were six-week observation periods before, between, and after the treatments. Three patients had acyclovir-induced nephrotoxicity and were withdrawn from the study.

Of the 24 patients who completed the trial, similar numbers improved with acyclovir therapy and with placebo (11 and 10, respectively). Neither acyclovir treatment nor clinical improvement correlated with alterations in laboratory findings, including titers of antibody to Epstein-Barr virus or levels of circulating immune complexes or of leukocyte 2′,5′-oligoadenylate synthetase. Subjective improvement correlated with various measures of mood.

We conclude that acyclovir, as used in this study, does not ameliorate the chronic fatigue syndrome. We believe that the clinical improvement observed in most patients reflected either spontaneous remission of the syndrome or a placebo effect.

 

Source: Straus SE, Dale JK, Tobi M, Lawley T, Preble O, Blaese RM, Hallahan C, Henle W. Acyclovir treatment of the chronic fatigue syndrome. Lack of efficacy in a placebo-controlled trial. N Engl J Med. 1988 Dec 29;319(26):1692-8. http://www.ncbi.nlm.nih.gov/pubmed/2849717

 

Chronic fatigue syndrome: a working case definition

Abstract:

The chronic Epstein-Barr virus syndrome is a poorly defined symptom complex characterized primarily by chronic or recurrent debilitating fatigue and various combinations of other symptoms, including sore throat, lymph node pain and tenderness, headache, myalgia, and arthralgias.

Although the syndrome has received recent attention, and has been diagnosed in many patients, the chronic Epstein-Barr virus syndrome has not been defined consistently. Despite the name of the syndrome, both the diagnostic value of Epstein-Barr virus serologic tests and the proposed causal relationship between Epstein-Barr virus infection and patients who have been diagnosed with the chronic Epstein-Barr virus syndrome remain doubtful.

We propose a new name for the chronic Epstein-Barr virus syndrome–the chronic fatigue syndrome–that more accurately describes this symptom complex as a syndrome of unknown cause characterized primarily by chronic fatigue. We also present a working definition for the chronic fatigue syndrome designed to improve the comparability and reproducibility of clinical research and epidemiologic studies, and to provide a rational basis for evaluating patients who have chronic fatigue of undetermined cause.

 

Source: Holmes GP, Kaplan JE, Gantz NM, Komaroff AL, Schonberger LB, Straus SE, Jones JF, Dubois RE, Cunningham-Rundles C, Pahwa S, et al. Chronic fatigue syndrome: a working case definition. Ann Intern Med. 1988 Mar;108(3):387-9. http://www.ncbi.nlm.nih.gov/pubmed/2829679

 

Allergy and the chronic fatigue syndrome

Abstract:

The chronic fatigue syndrome is a heterogeneous disorder characterized by easy fatigability, feverishness, diffuse pains, and depression. Many patients also report inhalant, food, or drug allergies.

This article reviews the clinical features of the syndrome and hypotheses of its pathogenesis, especially those regarding the Epstein-Barr virus and cellular immune mechanisms. Also summarized are recent studies of the validity of atopic complaints in the syndrome.

The results of epicutaneous skin testing demonstrated a high correlation with history in 24 patients. Atopy coexists with the chronic fatigue syndrome in greater than 50% of patients.

 

Source: Straus SE, Dale JK, Wright R, Metcalfe DD. Allergy and the chronic fatigue syndrome. J Allergy Clin Immunol. 1988 May;81(5 Pt 1):791-5. http://www.ncbi.nlm.nih.gov/pubmed/2836490