Tag: Natelson

Cardiovascular responses of women with chronic fatigue syndrome to stressful cognitive testing before and after strenuous exercise

Abstract:

OBJECTIVE: The purpose of this study was to compare the cardiovascular responses of patients with chronic fatigue syndrome (CFS) to healthy control subjects when performing stressful cognitive tasks before and after strenuous exercise.

METHOD: Beat-by-beat blood pressure and electrocardiogram were recorded on 19 women with CFS and 20 healthy nonexercising (ie, sedentary) women while they performed cognitive tests before, immediately after, and 24 hours after incremental exercise to exhaustion.

RESULTS: Diminished heart rate (p <.01) and systolic (p <.01) and diastolic (p <.01) blood pressure responses to stressful cognitive testing were seen in patients with CFS when compared with healthy, sedentary controls. This diminished stress response was seen consistently in patients with CFS across three separate cognitive testing sessions. Also, significant negative correlations between self-ratings of CFS symptom severity and cardiovascular responses were seen (r = -0.62, p <.01).

CONCLUSIONS: Women with CFS have a diminished cardiovascular response to cognitive stress; however, exercise did not magnify this effect. Also, the data showed that the patients with the lowest cardiovascular reactivity had the highest ratings of CFS symptom severity, which suggests that the individual response of the patient with CFS to stress plays a role in the common complaint of symptoms worsening after stress.

 

Source: LaManca JJ, Peckerman A, Sisto SA, DeLuca J, Cook S, Natelson BH. Cardiovascular responses of women with chronic fatigue syndrome to stressful cognitive testing before and after strenuous exercise. Psychosom Med. 2001 Sep-Oct;63(5):756-64. http://www.ncbi.nlm.nih.gov/pubmed/11573024

 

Longitudinal assessment of neuropsychological functioning, psychiatric status, functional disability and employment status in chronic fatigue syndrome

Abstract:

The longitudinal course of subjective and objective neuropsychological functioning, psychological functioning, disability level, and employment status in chronic fatigue syndrome (CFS) was examined. The relations among several key outcomes at follow-up, as well as the baseline characteristics that predict change (e.g., improvement), were also evaluated.

The study sample consisted of 35 individuals who met the 1988 and 1994 CFS case definition criteria of the Centers for Disease Control (CDC) at intake. Participants were evaluated a mean of 41.9 (SEM = 1.7) months following their initial visit (range = 24-63 months).

Results indicated that objective and subjective attention abilities, mood, level of fatigue, and disability improve over time in individuals with CFS. Moreover, improvements in these areas were found to be interrelated at follow-up. Finally, psychiatric status, age, and between-test duration were significant predictors of outcome. Overall, the prognosis for CFS appears to be poor, as the majority of participants remained functionally impaired over time and were unemployed at follow-up, despite the noted improvements.

 

Source: Tiersky LA, DeLuca J, Hill N, Dhar SK, Johnson SK, Lange G, Rappolt G, Natelson BH. Longitudinal assessment of neuropsychological functioning, psychiatric status, functional disability and employment status in chronic fatigue syndrome. Appl Neuropsychol. 2001;8(1):41-50. http://www.ncbi.nlm.nih.gov/pubmed/11388123

 

Quantitative assessment of cerebral ventricular volumes in chronic fatigue syndrome

Abstract:

Previous qualitative volumetric assessment of lateral ventricular enlargement in chronic fatigue syndrome (CFS) has provided evidence for subtle structural changes in the brains of some individuals with CFS. The aim of this pilot study was to determine whether a more sensitive quantitative assessment of the lateral ventricular system would support the previous qualitative findings.

In this study, we compared the total lateral ventricular volume, as well as the right and left hemisphere subcomponents in 28 participants with CFS and 15 controls. Ventricular volumes in the CFS group were larger than in control groups, a difference that approached statistical significance. Group differences in ventricular asymmetry were not observed. The results of this study provide further evidence of subtle pathophysiological changes in the brains of participants with CFS.

 

Source: Lange G, Holodny AI, DeLuca J, Lee HJ, Yan XH, Steffener J, Natelson BH. Quantitative assessment of cerebral ventricular volumes in chronic fatigue syndrome. Appl Neuropsychol. 2001;8(1):23-30. http://www.ncbi.nlm.nih.gov/pubmed/11388120

 

Detection of immunologically significant factors for chronic fatigue syndrome using neural-network classifiers

Abstract:

Neural-network classifiers were used to detect immunological differences in groups of chronic fatigue syndrome (CFS) patients that heretofore had not shown significant differences from controls. In the past linear methods were unable to detect differences between CFS groups and non-CFS control groups in the nonveteran population.

An examination of the cluster structure for 29 immunological factors revealed a complex, nonlinear decision surface. Multilayer neural networks showed an over 16% improvement in an n-fold resampling generalization test on unseen data. A sensitivity analysis of the network found differences between groups that are consistent with the hypothesis that CFS symptoms are a consequence of immune system dysregulation.

Corresponding decreases in the CD19(+) B-cell compartment and the CD34(+) hematopoietic progenitor subpopulation were also detected by the neural network, consistent with the T-cell expansion. Of significant interest was the fact that, of all the cytokines evaluated, the only one to be in the final model was interleukin-4 (IL-4). Seeing an increase in IL-4 suggests a shift to a type 2 cytokine pattern. Such a shift has been hypothesized, but until now convincing evidence to support that hypothesis has been lacking.

 

Source: Hanson SJ, Gause W, Natelson B. Detection of immunologically significant factors for chronic fatigue syndrome using neural-network classifiers. Clin Diagn Lab Immunol. 2001 May;8(3):658-62. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC96120/ (Full article)

 

Relationship of brain MRI abnormalities and physical functional status in chronic fatigue syndrome

Abstract:

Chronic Fatigue Syndrome (CFS) is an unexplained illness that is characterized by severe fatigue. Some have suggested that CFS is a “functional somatic syndrome” in which symptoms of fatigue are inappropriately attributed to a serious illness. However, brain magnetic resonance imaging (MRI) data suggest that there may be an organic abnormality associated with CFS.

To understand further the significance of brain MRI abnormalities, we examined the relationship between MRI identified brain abnormalities and self-reported physical functional status in 48 subjects with CFS who underwent brain MR imaging and completed the Medical Outcomes Study SF-36. Brain MR images were examined for the presence of abnormalities based on 5 general categories previously shown to be sensitive to differentiating CFS patients from healthy controls.

There were significant negative relationships between the presence of brain abnormalities and both the physical functioning (PF) (rho=-.31, p=.03), and physical component summary PCS (rho=-.32, p=.03) subscales of the SF-36. CFS patients with MRI identified brain abnormalities scored significantly lower on both PF (t(1,46) =2.3, p=.026) and the PCS (t(1,41) =2.4, p=.02) than CFS subjects without an identified brain abnormality. When adjusted for age differences only the PF analysis remained significant. However, the effect sizes for both analyses were large indicating meaningful differences in perceived functional status between the groups.

These results demonstrate that the presence of brain abnormalities in CFS are significantly related to subjective reports of physical function and that CFS subjects with MRI brain abnormalities report being more physically impaired than those patients without brain abnormalities.

 

Source: Cook DB, Lange G, DeLuca J, Natelson BH. Relationship of brain MRI abnormalities and physical functional status in chronic fatigue syndrome. Int J Neurosci. 2001 Mar;107(1-2):1-6. http://www.ncbi.nlm.nih.gov/pubmed/11328679

 

Clinicopathological findings consistent with primary Sjögren’s syndrome in a subset of patients diagnosed with chronic fatigue syndrome: preliminary observations

Abstract:

OBJECTIVE: Some patients diagnosed with chronic fatigue syndrome (CFS) have symptoms commonly observed in Sjögren’s syndrome (SS), particularly xerophthalmia and xerostomia, leading to speculation that some patients with CFS might have primary SS or that the 2 disorders share common pathophysiological features. We investigated the prevalence of symptoms of mucosal dryness, salivary gland pathology, lacrimal hyposecretion, and autoantibodies (antinuclear antibody, SSA/SSB) among patients diagnosed with CFS.

METHODS: Twenty-five subjects with CFS and 18 healthy control subjects were interviewed and examined, had a Schirmer test and fluorescein tear dilution, and underwent minor salivary gland (MSG) biopsy. Antibody to nuclear antigen as well as anti-La (SSA) and anti-Ro (SSB) antibody were available for subjects with CFS. Pathologists unaware of the subject group assignment examined labial salivary gland biopsy specimens and calculated a standard MSG score for each specimen.

RESULTS: Mucosal dryness was reported by 13/25 (52%) subjects with CFS, of which 8 (32%) also had MSG score, low Schirmer test value, and symptoms consistent with primary SS (p = 0.05). No control subject met diagnostic criteria for primary SS. MSG focus scores < or =1 were common among both groups (CFS 14/25; controls 15/18). MSG results without pathological alteration were rare, seen in only one control and no CFS patients. Low Schirmer values were found in 10/25 (40%) CFS patients and 1/18 (6%) control (p = 0.01).

CONCLUSION: A subset of patients with CFS may have primary SS.

 

Source: Sirois DA, Natelson B. Clinicopathological findings consistent with primary Sjögren’s syndrome in a subset of patients diagnosed with chronic fatigue syndrome: preliminary observations. J Rheumatol. 2001 Jan;28(1):126-31. http://www.ncbi.nlm.nih.gov/pubmed/11196514

 

Hormonal responses to exercise in chronic fatigue syndrome

Abstract:

Chronic fatigue syndrome (CFS) is a debilitating disease characterized by severe, unexplained fatigue and postexertional exacerbation of symptoms. We examined basal endocrine function in a group of CFS patients and a carefully matched group of sedentary controls. The subjects then completed a graded, maximal exercise test on a treadmill, and additional blood samples were drawn 4 min and a day after the end of exercise.

There were no differences in basal hormone levels before exercise. Plasma adrenocorticotropin, epinephrine, prolactin and thyrotropin responses 4 min after exercise were lower in the CFS group, but the growth hormone response may have been exaggerated, and the plasma norepinephrine response was similar to that in controls.

The next day, there were no differences in hormone levels between the groups, which suggests that long-term changes in endocrine function are unlikely to be a cause of the prolonged fatigue that occurs in CFS patients after a bout of exertion.

 

Source: Ottenweller JE, Sisto SA, McCarty RC, Natelson BH. Hormonal responses to exercise in chronic fatigue syndrome. Neuropsychobiology. 2001 Jan;43(1):34-41. http://www.ncbi.nlm.nih.gov/pubmed/11150897

 

Stressors, personality traits, and coping of Gulf War veterans with chronic fatigue

Abstract:

OBJECTIVES: preliminary surveys of Persian Gulf veterans revealed a significant prevalence of self-reported symptoms consistent with chronic fatigue syndrome (CFS). The purpose of this study was to compare self-reported life stressors, combat, and chemical exposures, personality and coping between Gulf War veterans with CFS and healthy veterans.

METHODS: following a complete physical, psychiatric, and neuropsychological evaluation, 45 healthy veterans, 35 veterans with CFS and co-morbid psychiatric disorder, and 23 veterans with CFS and no co-morbid psychiatric disorder completed questionnaires assessing war and non-war-related life stressors, self-reports of environmental exposure (e.g. oil well fires, pesticides), personality, and coping.

RESULTS: measures of personality, self-reported combat and chemical exposures, and negative coping strategies significantly differentiated healthy veterans from those with CFS.

CONCLUSION: a biopsychosocial model of veterans’ illness was supported by the fact that personality, negative coping strategies, life stress after the war, and environmental exposures during the war were significant predictors of veterans’ current physical function.

 

Source: Fiedler N, Lange G, Tiersky L, DeLuca J, Policastro T, Kelly-McNeil K, McWilliams R, Korn L, Natelson B. Stressors, personality traits, and coping of Gulf War veterans with chronic fatigue. J Psychosom Res. 2000 Jun;48(6):525-35. http://www.ncbi.nlm.nih.gov/pubmed/11033371

 

Psychological profile and ventilatory response to inspiratory resistive loading

Abstract:

The purpose of this study was to explore the contribution of psychological state to both the ventilatory response and the intensity of dyspnea experienced after the addition of small inspiratory loads to breathing. We hypothesized that patients with either a specific psychiatric diagnosis or a specific psychological trait will associate a greater degree of dyspnea with a loaded breathing task than will control subjects.

To insure the inclusion of persons with relevant psychological profiles, we recruited both subjects enrolled in the Chronic Fatigue Center and normal control subjects. In all, 52 subjects inspired first through a small (1.34 cm H(2)O/L/s) and second through a moderate (3.54 cm H(2)O/L/s) inspiratory resistive load (IRL). Ventilation was monitored throughout the 5-min sessions. Dyspnea was quantified with the Borg scale at specified times during the protocol. Standard psychological tests were administered.

We found that subjects could be divided into two groups. One, the “responders,” reported Borg scores higher than those of the second, or “nonresponder” group, at all times during the protocol. By contrast, there was no difference between groups with respect to ventilation. Responders had higher scores on tests of depression (the Center for Epidemiological Study depression scale) than did nonresponders. We conclude that the variability observed in subjective responses to IRL is explained, in part, by differences in psychological state.

 

Source: Lavietes MH, Sanchez CW, Tiersky LA, Cherniack NS, Natelson BH. Psychological profile and ventilatory response to inspiratory resistive loading. Am J Respir Crit Care Med. 2000 Mar;161(3 Pt 1):737-44. http://www.ncbi.nlm.nih.gov/pubmed/10712316

 

Chronic fatigue syndrome beginning suddenly occurs seasonally over the year

Abstract:

The fact that many patients with chronic fatigue syndrome (CFS) have an infectious like sudden onset to their illness has led to the hypothesis that CFS is a medical illness. If CFS were, on the other hand, a psychiatric disorder related to symptom amplification, one would expect illness onset to occur randomly over the calendar year.

This study tested that hypothesis with 69 CFS patients whose illness was on the more severe side of the illness spectrum; all patients reported sudden illness onset with the full syndrome of sore throat, fatigue/malaise, and diffuse achiness developing over no longer than a 2-day period. Date of illness onset was distinctly nonrandom. It peaked from November through January and was at its lowest from April through May. These data support the hypothesis that an infectious illness can trigger the onset of CFS.

 

Source: Zhang QW, Natelson BH, Ottenweller JE, Servatius RJ, Nelson JJ, De Luca J, Tiersky L, Lange G. Chronic fatigue syndrome beginning suddenly occurs seasonally over the year. Chronobiol Int. 2000 Jan;17(1):95-9. http://www.ncbi.nlm.nih.gov/pubmed/10672437