Tag: subgroups

Cognitive behaviour therapy for the chronic fatigue syndrome. Patients were not representative of all patients with the syndrome.

Comment on: Cognitive behaviour therapy for the chronic fatigue syndrome: a randomized controlled trial. [BMJ. 1996]

 

EDITOR,-Michael Sharpe and colleagues conclude that cognitive behaviour therapy leads to a sustained reduction in functional impairment for patients with the chronic fatigue syndrome.1 The levels of disability of the 60 patients who took part in the study suggest, however, that these patients do not represent a comprehensive cross section of patients with the syndrome. The 60 patients scored 60-78 on the Karnofsky scale assessing disability and so represent a different population from the 143 patients reported on by Case History Research on ME (myalgic encephalomyelitis), who would have scored 30-60 (R Gibbons et al, first world congress on chronic fatigue syndrome and related disorders, Brussels, Nov 1995). Fifty nine of these 143 patients reported functional deterioration after sustained, incrementally increased physical exertion.

The authors did not assess other symptoms common in the chronic fatigue syndrome, such as pain, nausea, muscle weakness, or balance problems-a measure of the reduction of which was taken as a standard for “success” in an earlier trial.2 The lack of evidence of significant changes in other measures besides “the principal complaint of severe fatigue” in the authors’ study tends to diminish the validity of their conclusions.

You can read the full comment here:  http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2350876/pdf/bmj00539-0052c.pdf

 

Source: Gibbons R, Macintyre A, Richards C. Cognitive behaviour therapy for the chronic fatigue syndrome. Patients were not representative of all patients with the syndrome. BMJ. 1996 Apr 27;312(7038):1096; author reply 1098. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2350876/

MMPI profiles of patients with chronic fatigue syndrome

Abstract:

Fifty-three patients with chronic fatigue syndrome (CFS) and 43 healthy nonpatient controls completed the Minnesota Multiphasic Personality Inventory (MMPI). All subjects varied in their degree of seropositivity to active Epstein-Barr virus (EBV) as measured by their anti-early antigen titers. EBV titers were higher among CFS patients and were associated with being more symptomatic.

Differences in patient status were associated with statistically significant elevations on 8 of 9 clinical scales, 4 of which also showed clinically significant elevations (T scores > or = 70): scales 1, 2, 3, and 8. These results are discussed in terms of their implications for intervention strategies associated with MMPI-based CFS subtypes.

 

Source: Schmaling KB, Jones JF. MMPI profiles of patients with chronic fatigue syndrome. J Psychosom Res. 1996 Jan;40(1):67-74. http://www.ncbi.nlm.nih.gov/pubmed/8730646

 

alpha-Interferon treatment of patients with chronic fatigue syndrome

Abstract:

Thirty patients who fulfilled clinical criteria defined by the CDC for Chronic Fatigue Syndrome were treated with alfa 2a interferon or placebo in a double-blind crossover study. Outcome was evaluated by Natural Killer (NK) cell function, lymphocyte proliferation to mitogens and soluble antigens, CD4/CD8 counts and a 10 item Quality of Life (QOL) survey.

Although mean NK function rose from 87.8 +/- 19.6 to 129.3 +/- 20.7 lytic untis (LU; p < .05) with 12 weeks of interferon therapy, there was no significant change in the other immunologic parameters or QOL scores. When the 26 patients who completed the study were stratified according to their baseline NK function and lymphocyte proliferation, 4 groups were identified: 3 patients had normal NK cell function and lymphocyte proliferation when compared to normal, healthy controls, 9 had isolated deficiency in lymphocyte proliferation, 7 had diminished NK function only, and 7 had abnormalities for both parameters.

QOL scores were not significantly different for the four groups at baseline. After 12 weeks of interferon therapy, QOL score significantly improved in each of the seven patients with isolated NK cell dysfunction (mean score, 16.3 +/- 7.9) compared to baseline (39.7 +/- 12.1; p < .05). In these patients the mean NK function increased from 35.1 +/- 11.7 to 91.5 +/- 22.7 LU (p < .01). Significant improvement was not recorded for QOL in the other three groups. Thus, therapy with alpha interferon has a significant effect on the QOL of that subgroup of patients with CFS manifesting an isolated decrease in NK function.

 

Source: See DM, Tilles JG. alpha-Interferon treatment of patients with chronic fatigue syndrome. Immunol Invest. 1996 Jan-Mar;25(1-2):153-64. http://www.ncbi.nlm.nih.gov/pubmed/8675231

 

Can the chronic fatigue syndrome be defined by distinct clinical features?

Abstract:

To determine whether patients diagnosed as having chronic fatigue syndrome (CFS) constitute a clinically homogeneous class, multivariate statistical analyses were used to derive symptom patterns and potential patient subclasses in 565 patients. The notion that patients currently diagnosed as having CFS constitute a single homogeneous class was rejected.

An alternative set of clinical subgroups was derived. The validity of these subgroups was assessed by sociodemographic, psychiatric, immunological and illness behaviour variables. A two-class statistical solution was considered most coherent, with patients from the smaller class (27% of the sample) having clinical characteristics suggestive of somatoform disorders. The larger class (73% of sample) presented a more limited combination of fatigue and neuropsychological symptoms, and only moderate disability but remained heterogeneous clinically. The two patient groups differed with regard to duration of illness, spontaneous recovery, severity of current psychological morbidity, utilization of medical services and CD8 T cell subset counts. The distribution of symptoms among patients was not unimodal, supporting the notion that differences between the proposed subclasses were not due simply to differences in symptom severity.

This study demonstrated clinical heterogeneity among patients currently diagnosed as CFS, suggesting aetiological heterogeneity. In the absence of discriminative clinical features, current consensus criteria do not necessarily reduce the heterogeneity of patients recruited to CFS research studies.

 

Source: Hickie I, Lloyd A, Hadzi-Pavlovic D, Parker G, Bird K, Wakefield D. Can the chronic fatigue syndrome be defined by distinct clinical features? Psychol Med. 1995 Sep;25(5):925-35. http://www.ncbi.nlm.nih.gov/pubmed/8588011

 

Dimensional assessment of chronic fatigue syndrome

Abstract:

The absence of laboratory tests and clear criteria to identify homogeneous (sub)groups in patients presenting with unexplained fatigue, and to assess clinical status and disability in these patients, calls for further assessment methods. In the present study, a multi-dimensional approach to the assessment of chronic fatigue syndrome (CFS) is evaluated.

Two-hundred and ninety-eight patients with CFS completed a set of postal questionnaires that assessed the behavioural, emotional, social, and cognitive aspects of CFS. By means of statistical analyses nine relatively independent dimensions of CFS were identified along which CFS-assessment and CFS-research can be directed.

These dimensions were named: psychological well-being, functional impairment in daily life, sleep disturbances, avoidance of physical activity, neuropsychological impairment, causal attributions related to the complaints, social functioning, self-efficacy expectations, and subjective experience of the personal situation. A description of the study sample on these dimensions is presented.

 

Source: Vercoulen JH, Swanink CM, Fennis JF, Galama JM, van der Meer JW, Bleijenberg G. Dimensional assessment of chronic fatigue syndrome. J Psychosom Res. 1994 Jul;38(5):383-92. http://www.ncbi.nlm.nih.gov/pubmed/7965927

 

The treatment of chronic fatigue syndrome: science and speculation

Abstract:

The chronic fatigue syndrome (CFS) is a heterogeneous disorder characterized by fatigue, neuropsychiatric symptoms, and various other somatic complaints. Treatment studies to date reflect both the diversity of medical disciplines involved in the management of patients with CFS and the multiple pathophysiologic mechanisms proposed.

There have been few attempts to study integrated treatment programs, and although several controlled studies have been reported, no treatment has been shown clearly to result in long-term benefit in the majority of patients. Good clinical care integrating medical and psychologic concepts, together with symptomatic management, may prevent significant secondary impairment in the majority of patients.

Future treatment studies should examine differential response rates for possible subtypes of the disorder (eg, documented viral onset, concurrent clinical depression), evaluate the extent of any synergistic effects between therapies (ie, medical and psychologic), and employ a wide range of biologic and psychologic parameters as markers of treatment response.

 

Source: Wilson A, Hickie I, Lloyd A, Wakefield D. The treatment of chronic fatigue syndrome: science and speculation. Am J Med. 1994 Jun;96(6):544-50. http://www.ncbi.nlm.nih.gov/pubmed/8017453

 

Chronic fatigue syndrome. Immunological findings vary between populations

Comment on: Longitudinal study of outcome of chronic fatigue syndrome. [BMJ. 1994]

 

Editor,-We were interested in Andrew Wilson and colleagues’ paper investigating predictors of the long term outcome of the chronic fatigue syndrome in patients in Australia. We have investigated the association between immune activation and presumed cutaneous anergy in 68 Scottish patients with the syndrome (19 cases conformed to the Centers for Disease Control’s criteria, 18 cases had been diagnosed by a consultant, 28 cases had been diagnosed by a general practitioner, and three patients referred themselves) and 22 family contacts. We assessed delayed hypersensitivity responses (using Multitest antigens and tuberculin skin tests) and evaluated peripheral blood activation markers (CD8, CD38/ CD llb/HLA-DR) using flow cytometry. Patients were classified into three groups on the basis of current severity of illness and mobility.

You can read the rest of this comment here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2540184/pdf/bmj00440-0055b.pdf

 

Source: Abbot NC, Spence VA, Lowe JG, Potts RC, Hassan AH, Belch JJ, Beck JS. Chronic fatigue syndrome. Immunological findings vary between populations. BMJ. 1994 May 14;308(6939):1299. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2540184/

 

High titers of anti-Epstein-Barr virus DNA polymerase are found in patients with severe fatiguing illness

Abstract:

Forty-one patients with chronic fatigue syndrome (CFS), 76 healthy controls matched with the patient group for age range, sex, race, and socioeconomic class, and 22 symptomatic patients with seasonal affective disorder (SAD) had serum sampled for antibodies against 2 Epstein-Barr virus (EBV) replicating enzymes.

Abnormal titers of antibodies were found twice as often in CFS patients as controls (34.1% vs. 17.1%), with SAD patients having an intermediate frequency (27.3%). Stratifying for disease severity sharpened the differences considerably, with the sicker CFS and SAD patients having 52% and 50% abnormal tests, respectively; more mildly afflicted CFS and SAD patients had a frequency of abnormal tests in the normal range.

Antibodies to EBV DNA polymerase (DNAP) were the more sensitive of the two tests in that they were positive in all cases but one. These findings suggest that antibodies against EBV DNAP may be a useful marker in delineating a subset of patients with severe fatiguing illness for appropriate treatment trials and for monitoring their outcomes.

 

Source: Natelson BH, Ye N, Moul DE, Jenkins FJ, Oren DA, Tapp WN, Cheng YC. High titers of anti-Epstein-Barr virus DNA polymerase are found in patients with severe fatiguing illness. J Med Virol. 1994 Jan;42(1):42-6. http://www.ncbi.nlm.nih.gov/pubmed/8308519

 

Decreased natural killer cell activity is associated with severity of chronic fatigue immune dysfunction syndrome

Abstract:

Natural killer (NK) cell activity was measured blindly in vitro with blood specimens from 50 healthy individuals and 20 patients with clinically defined chronic fatigue immune dysfunction syndrome (CFIDS) who met the criteria established by the Centers for Disease Control and Prevention (Atlanta).

In accordance with a group scoring system of 1-10 points, with 10 being the most severe clinical status, the patient population was stratified into three clinical groups: A (> 7 points), B (5-7 points), and C (< 5 points). NK cell activity was assessed by the number of lytic units (LU), which for the 50 healthy controls varied between 20 and 250 (50%, 20-50 LU; 32%, 51-100 LU; 6%, 101-130 LU; and 12%, > 150 LU).

In none of the 20 patients with CFIDS was the NK cell activity > 100 LU. For group C, the 10 patients stratified as having the least severe clinical condition, the measure was 61.0 +/- 21.7 LU; for group B (more severe, n = 7), it was 18.3 +/- 7.3 LU; and for group A (most severe, n = 3), it was 8.0 +/- 5.3 LU.

These data suggest a correlation between low levels of NK cell activity and severity of CFIDS, which, if it is confirmed by additional studies of larger groups, might be useful for subgrouping patients and monitoring therapy and/or the progression of CFIDS.

 

Source: Ojo-Amaize EA, Conley EJ, Peter JB. Decreased natural killer cell activity is associated with severity of chronic fatigue immune dysfunction syndrome. Clin Infect Dis. 1994 Jan;18 Suppl 1:S157-9. http://www.ncbi.nlm.nih.gov/pubmed/8148445

 

Defining the chronic fatigue syndrome

Abstract:

The recently published working definition of the chronic fatigue syndrome (CFS) is a necessary first step toward a consistent effort to research this controversial illness. Before this definition was developed, cases often were defined vaguely, according to the perceptions and biases of the individual researchers, so that the results of some studies were unclear. However, few specific diagnostic parameters for CFS exist, and the new definition may not delineate a single clinicopathologic entity.

Future efforts at researching this illness should be aimed at identifying parameters that differentiate CFS from psychiatric conditions such as major depression and from other defined chronic diseases. Because CFS may be the result of multiple disease processes, the separate study of well-defined subgroups of patients with CFS is appropriate.

Such subgroups of patients are probably more likely to have common pathogenetic features than are patients with CFS as a whole group.

 

Source: Holmes GP. Defining the chronic fatigue syndrome. Rev Infect Dis. 1991 Jan-Feb;13 Suppl 1:S53-5. http://www.ncbi.nlm.nih.gov/pubmed/2020802