Commentary on: randomised, double-blind, placebo-controlled trial of fluoxetine and graded exercise for chronic fatigue syndrome

Systematic review of randomized controlled trials for chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME)

BACKGROUND

Although medical requirements are urgent, no effective intervention has been proven for chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME). To facilitate the development of new therapeutics, we systematically reviewed the randomized controlled trials (RCTs) for CFS/ME to date.

METHODS

RCTs targeting CFS/ME were surveyed using two electronic databases, PubMed and the Cochrane library, through April 2019. We included only RCTs that targeted fatigue-related symptoms, and we analyzed the data in terms of the characteristics of the participants, case definitions, primary measurements, and interventions with overall outcomes.

RESULTS

Among 513 potentially relevant articles, 55 RCTs met our inclusion criteria; these included 25 RCTs of 22 different pharmacological interventions, 28 RCTs of 18 non-pharmacological interventions and 2 RCTs of combined interventions. These studies accounted for a total of 6316 participants (1568 males and 4748 females, 5859 adults and 457 adolescents). CDC 1994 (Fukuda) criteria were mostly used for case definitions (42 RCTs, 76.4%), and the primary measurement tools included the Checklist Individual Strength (CIS, 36.4%) and the 36-item Short Form health survey (SF-36, 30.9%). Eight interventions showed statistical significance: 3 pharmacological (Staphypan Berna, Poly(I):poly(C12U) and CoQ10 + NADH) and 5 non-pharmacological therapies (cognitive-behavior-therapy-related treatments, graded-exercise-related therapies, rehabilitation, acupuncture and abdominal tuina). However, there was no definitely effective intervention with coherence and reproducibility.

CONCLUSIONS

This systematic review integrates the comprehensive features of previous RCTs for CFS/ME and reflects on their limitations and perspectives in the process of developing new interventions.

Prediction of peak oxygen uptake in patients fulfilling the 1994 CDC criteria for chronic fatigue syndrome

Purpose: To establish an inexpensive, simple method of predicting peak oxygen uptake (VO2peak) in patients fulfilling the 1994 Centers for Disease Control and Prevention (CDC) criteria for chronic fatigue syndrome (CFS).

Design: A retrospective observational study.

Setting: An outpatient tertiary care chronic fatigue clinic.

Subjects: Two hundred and forty consecutive patients fulfilling the 1994 CDC criteria for CFS.

Interventions: Heart rate, metabolic and ventilatory parameters were measured continuously during a maximal exercise stress test on a bicycle ergometer. Using the equation peak oxygen uptake / 13.1 / peak workload / 284 (used by Mullis et al., Br J Sports Med1999; 33: 352 / 56), VO2peak was predicted from the peak workload of a maximal exercise capacity test. Pearson correlation coefficient and linear regression analysis were used to establish the most accurate way to predict VO2peak.

Results: Percentage error encountered when comparing actual measured Vo2peak with predicted value was 17.3% (9-10.0). A strong correlation between Vo2peak and peak workload was observed (r / 0.89, p< 0.001). A regression analysis established the relation as Vo2peak= 10.47 × peak workload +284.1, where Vo2peak is given in ml/min and peak workload in W (error in prediction = 11.09±9.5%).

Conclusions: Monitoring of the peak workload during a maximal, graded bicycle ergometric test suffices to predict the Vo2peak. When predicting Vo2peak the used operational definition for the diagnosis of CFS could be taken into account. Compared with the equation used by Mullis et al., peak workload is multiplied by 10.47 in order to predict peak oxygen uptake in CDC-defined CFS patients.

Open-label study of s-citalopram therapy of chronic fatigue syndrome and co-morbid major depressive disorder

OBJECTIVE

Chronic fatigue syndrome (CFS) is a debilitating disorder with prominent symptoms of malaise, fatigue, myalgia, arthralgia, and impaired concentration. The symptoms of CFS may often overlap those of Major Depressive Disorder (MDD). Treatment of CFS has generally been disappointing. We hypothesized that s-citalopram therapy may improve the symptoms of both disorders in CFS patients with co-morbid depression.

METHODS

16 patients received s-citalopram 10 mg to 20 mg daily for up to 12 weeks. Outcome measures of CFS included the Chalder Fatigue Questionnaire (CFQ), the multi-dimensional Fatigue Impact Scale (FIS), the CFS symptom rating (CFS-SR) 100 mm visual analogue scale, and the clinical global impressions severity (CGI/S) and change (CGI/C) ratings. Secondary outcomes of MDD included the Hamilton Depression Rating (HAM-D), Beck Depression Inventory (BDI), and the CGI/S and CGI/C ratings of MDD.

RESULTS

We observed reductions in the mean CFQ score (p<0.0005), FIS score (p<0.0005), and CGI/S (p<0.0005) and CGI/C (p<0.0005) ratings over time. There was a significant improvement in 5 of the 8 CFS-SR symptoms: post-exertion malaise (p=0.001), headaches (p<0.0005), un-refreshing sleep (p<0.0005), and impaired memory and concentration (p<0.0005). There was also a reduction in mean HAM-D (p<0.0005), BDI (p<0.0005), CGI/S (p=0.001) and CGI/C (p<0.0005) ratings of MDD.

LIMITATIONS

The sample size was limited and the study design was not double-blind or placebo controlled.

CONCLUSION

We observed a significant reduction in both CFS and co-morbid MDD symptom severity ratings, and improvement in 5 of 8 core somatic symptoms of CFS during s-citalopram therapy.

Exercise therapy for chronic fatigue syndrome

BACKGROUND

Chronic fatigue syndrome (CFS) is an illness characterised by persistent medically unexplained fatigue. CFS is a serious health-care problem with a prevalence of up to 3%. Treatment strategies for CFS include psychological, physical and pharmacological interventions.

OBJECTIVES

To investigate the relative effectiveness of exercise therapy and control treatments for CFS.

SEARCH STRATEGY

CCDANCTR-Studies and CENTRAL were searched using "Chronic Fatigue" and Exercise. The Journal of Chronic Fatigue Syndrome and CFS conferences were handsearched. Experts in the field were contacted. Clinicaltrials.gov and controlled-trials.com were searched.

SELECTION CRITERIA

Only Randomised Controlled Trials (RCT) including participants with a clinical diagnosis of CFS and of any age were included.

DATA COLLECTION AND ANALYSIS

The full articles of studies identified were inspected by two reviewers (ME and HMG). Continuous measures of outcome were combined using standardised mean differences. An overall effect size was calculated for each outcome with 95% confidence intervals. One sensitivity analysis was undertaken to test the robustness of the results.

MAIN RESULTS

Nine studies were identified for possible inclusion in this review, and five of those studies were included. At 12 weeks, those receiving exercise therapy were less fatigued than the control participants (SMD -0.77, 95% CIs -1.26 to -0.28). Physical functioning was significantly improved with exercise therapy group (SMD -0.64, CIs -0.96 to -0.33) but there were more dropouts with exercise therapy (RR 1.73, CIs 0.92 to 3.24). Depression was non-significantly improved in the exercise therapy group compared to the control group at 12 weeks (WMD -0.58, 95% CIs -2.08 to 0.92). Participants receiving exercise therapy were less fatigued than those receiving the antidepressant fluoxetine at 12 weeks (WMD -1.24, 95% CIs -5.31 to 2.83). Participants receiving the combination of the two interventions, exercise + fluoxetine, were less fatigued than those receiving exercise therapy alone at 12 weeks, although again the difference did not reach significance (WMD 3.74, 95% CIs -2.16 to 9.64). When exercise therapy was combined with patient education, those receiving the combination were less fatigued than those receiving exercise therapy alone at 12 weeks (WMD 0.70, 95% CIs -1.48 to 2.88).

REVIEWERS' CONCLUSIONS

There is encouraging evidence that some patients may benefit from exercise therapy and no evidence that exercise therapy may worsen outcomes on average. However the treatment may be less acceptable to patients than other management approaches, such as rest or pacing. Patients with CFS who are similar to those in these trials should be offered exercise therapy, and their progress monitored Further high quality randomised studies are needed.

The neglect of somatoform disorders by old age psychiatry: some explanations and suggestions for future research

AIM

The somatoform disorders have long been ignored by old age psychiatry. The main aim of this paper is to identify and examine possible reasons for this neglect.

METHOD

A selective review of the general literature on somatoform disorders.

RESULTS

Significant conceptual, diagnostic and classificatory problems have impeded the consideration of somatoform disorders in older people. There is a perception that somatoform disorders are infrequent and have not been validated as independent clinical disorders. However, we present evidence that the more broadly defined somatoform disorders are common in all age groups in primary care and meet criteria for the determination of clinical validity. General difficulties in the assessment of psychiatric disorders in primary care, the setting in which somatoform disorders are most common, are compounded by a lack of support from old age psychiatry services. Effective psychological therapies may not be readily available to sufferers.

CONCLUSION

There is a need for change in the conceptualisation and nosology of the somatoform disorders. The formulation of age appropriate diagnostic criteria and presentations is a prerequisite for determining the clinical validity of these disorders in older people. This can be followed by study of their frequency, associated risk factors and treatment. A system of education that enhances the management of these disorders within primary care and old age psychiatry services is needed.