The planning, implementation and publication of a complex intervention trial for chronic fatigue syndrome: the PACE trial

Fatigue in IBD: epidemiology, pathophysiology and management

Fatigue is an important clinical problem in patients with IBD, affecting nearly 50% of patients in clinical remission and > 80% of those with active disease. The resulting decrease in quality of life and impaired work productivity and functioning contribute markedly to the societal costs of fatigue. However, despite the burden and effects of fatigue, little is known about its aetiology and pathophysiology, which impairs our ability to effectively treat this symptom. Here, we review the theories behind the development of fatigue in IBD and the role of contributing factors, including nutritional deficiency, inflammation and altered metabolism. We also explore the potential role of the gut microbiome in mediating fatigue and other psychological symptoms through the gut-brain axis. We discuss the efficacy of nutrient repletion and various psychological and pharmacological interventions on relieving fatigue in patients with IBD and expand the discussion to non-IBD-related fatigue when evidence exists. Finally, we present a therapeutic strategy for the management of fatigue in IBD and call for further mechanistic and clinical research into this poorly studied symptom.

Response: Sharpe, Goldsmith and Chalder fail to restore confidence in the PACE trial findings

In a recent paper, we argued that the conclusions of the PACE trial of chronic fatigue syndrome are problematic because the pre-registered protocol was not adhered to. We showed that when the originally specific outcomes and analyses are used, the evidence for the effectiveness of CBT and graded exercise therapy is weak. In a companion paper to this article, Sharpe, Goldsmith and Chalder dismiss the concerns we raised and maintain that the original conclusions are robust. In this rejoinder, we clarify one misconception in their commentary, and address seven additional arguments they raise in defence of their conclusions. We conclude that none of these arguments is sufficient to justify digressing from the pre-registered trial protocol. Specifically, the PACE authors view the trial protocol as a preliminary plan, subject to honing and improvement as time progresses, whereas we view it as a contract that should not be broken except in extremely unusual circumstances. While the arguments presented by Sharpe and colleagues inspire some interesting reflections on the scientific process, they fail to restore confidence in the PACE trial’s conclusions.

Controversy over exercise therapy for chronic fatigue syndrome: Continuing the debate

In a recent Round the Corner, Mitchell commented on a Cochrane Review of exercise therapy for chronic fatigue syndrome (CFS). One of the trials included in that review, and discussed by Mitchell, was the PACE trial. In this month's Round the Corner we are publishing a response we received from authors of the PACE trial (Chalder, White & Sharpe), together with Mitchell's reply. Ed.

Rethinking the treatment of chronic fatigue syndrome-a reanalysis and evaluation of findings from a recent major trial of graded exercise and CBT

BACKGROUND

The PACE trial was a well-powered randomised trial designed to examine the efficacy of graded exercise therapy (GET) and cognitive behavioural therapy (CBT) for chronic fatigue syndrome. Reports concluded that both treatments were moderately effective, each leading to recovery in over a fifth of patients. However, the reported analyses did not consistently follow the procedures set out in the published protocol, and it is unclear whether the conclusions are fully justified by the evidence.

METHODS

Here, we present results based on the original protocol-specified procedures. Data from a recent Freedom of Information request enabled us to closely approximate these procedures. We also evaluate the conclusions from the trial as a whole.

RESULTS

On the original protocol-specified primary outcome measure - overall improvement rates - there was a significant effect of treatment group. However, the groups receiving CBT or GET did not significantly outperform the Control group after correcting for the number of comparisons specified in the trial protocol. Also, rates of recovery were consistently low and not significantly different across treatment groups. Finally, on secondary measures, significant effects were almost entirely confined to self-report measures. These effects did not endure beyond two years.

CONCLUSIONS

These findings raise serious concerns about the robustness of the claims made about the efficacy of CBT and GET. The modest treatment effects obtained on self-report measures in the PACE trial do not exceed what could be reasonably accounted for by participant reporting biases.

Somatoform disorder as a predictor of interstitial cystitis/bladder pain syndrome: Evidence from a nested case-control study and a retrospective cohort study

Interstitial cystitis/bladder pain syndrome (IC/BPS) has several well-known comorbid psychiatric manifestations, including insomnia, anxiety, and depression. We hypothesized that somatoform disorder, which is a psychosomatic disease, can be used as a sensitive psychiatric phenotype of IC/BPS. We investigated whether somatoform disorder increases the risk of IC/BPS.A nested case-control study and a retrospective cohort study were followed up over a 12-year period (2002-2013) in the Taiwan Health Insurance Reimbursement Database. In the nested case-control study, 1612 patients with IC/BPS were matched in a 1:2 ratio to 3224 controls based on propensity scores. The odds ratio for somatoform disorder was calculated using conditional logistic regression analysis. In the retrospective cohort study, 1436 patients with somatoform disorder were matched in a 1:2 ratio to 2872 patients with nonsomatoform disorder based on propensity scores. Cox regression analysis was used to estimate the hazard ratio associated with the development of IC/BPS in patients with somatoform disorder, and the cumulative survival probability was tested using the Kaplan-Meier analysis.We found that the odds ratio for somatoform disorder was 2.46 (95% confidence interval [CI], 1.05-5.76). Although the average time until IC/BPS development in the control subjects was 11.5 ± 1.3 years, this interval was shorter in patients with somatoform disorder (6.3 ± 3.6 years). The hazard ratio for developing IC/BPS was 2.50 (95% CI 1.23-5.58); the adjusted hazard ratio was 2.26 (95% CI 1.002-5.007). The patients and controls also differed significantly in their cumulative survival probability for IC/BPS (log rank P < .05).Evidence from the nested case-control study and retrospective cohort study consistently indicated that somatoform disorder increases the risk for IC/BPS. Our study suggests that somatoform disorder can be used as a sensitive psychiatric phenotype to predict IC/BPS. Any past history of somatoform disorder should be documented while examining patients with IC/BPS.

Nutritional advice for community patients: insights from a panel discussion

This article describes the conclusions of an expert panel that discussed four case studies; these were examples of patients typically encountered by nurses working in the community. The panel considered the nutritional and lifestyle advice that could be given by nurses relating to conditions such as irritable bowel syndrome (IBS), depression, chronic fatigue syndrome, vulnerability to common infections, elderly care, recurrent urinary tract infection, antibiotic use, and risk of type 2 diabetes. A general conclusion was the importance of motivational interviewing techniques in achieving full understanding of patients' concerns and to determine the best health strategy. As well as specific guidance appropriate for each disorder, a range of information sources for both health professionals and patients are listed in the paper. The panel noted that, although general nutritional advice can be given by nurses working at GP surgeries and in the community, patients should always be referred to registered dietitians or nutritionists if significant dietary changes are considered.