Does the effect of cognitive behavior therapy for chronic fatigue syndrome (ME/CFS) vary by patient characteristics? A systematic review and individual patient data meta-analysis

Is the effect of cognitive behaviour therapy for chronic fatigue syndrome (ME/CFS) moderated by the presence of comorbid depressive symptoms? A meta-analysis of three treatment delivery formats

OBJECTIVE

Cognitive behaviour therapy (CBT) for fatigue in chronic fatigue syndrome (ME/CFS) leads to a significant reduction of fatigue and disability and is available in different treatment delivery formats, i.e. internet-based, individual face-to-face and group face-to-face. The aim of this study was to investigate whether moderation of the effects of CBT by clinically relevant depressive symptoms varies between CBT delivery formats.

METHODS

Data from six randomised controlled trials (n = 1084 patients) were pooled. Moderation of clinically relevant depressive symptoms (Brief Depression Inventory for Primary Care) in different treatment formats on fatigue severity (Checklist Individual Strength, subscale fatigue severity), functional impairment (Sickness Impact Profile-8) and physical functioning (Short Form-36, subscale physical functioning) was investigated using linear mixed model analyses and interaction tests. Differences in percentages of patients no longer severely fatigued post-CBT were studied by calculating relative risks.

RESULTS

The moderator effect of depressive symptoms on fatigue severity varied by delivery format. In internet-based CBT, ME/CFS patients with depressive symptoms showed less reduction in fatigue, and were more often still severely fatigued post-treatment than patients without depressive symptoms. In individual and group face-to-face CBT, no significant difference in treatment effect on fatigue severity was found between patients with and without depressive symptoms. No moderation was found for the other outcomes.

CONCLUSION

In internet-based CBT, ME/CFS patients with comorbid depressive symptoms benefit less, making face-to-face CBT currently the first-choice delivery format for these patients. Internet-based CBT should be further developed to improve its effectiveness for ME/CFS patients with depressive symptoms.

Efficacy and Acceptance of Cognitive Behavioral Therapy in Adults with Chronic Fatigue Syndrome: A Meta-analysis

BACKGROUND

The systematic aggregation of research on cognitive behavioral therapy (CBT) in chronic fatigue syndrome (CFS) needs an update. Although meta-analyses evaluating interventions typically focus on symptom reduction, they should also consider indicators of treatment acceptability, e.g., drop-out rates.

METHODS

Randomized controlled trials (RCTs) investigating CBT in adults with CFS compared to inactive and non-specific control groups were included. First, efficacy was examined, considering fatigue, depression, anxiety, and perceived health. Secondly, drop-out rates through different trial stages were analyzed: Non-completion of all mandatory sessions, drop-out (primary study definition), treatment refusal (non-starters), and average of sessions completed.

RESULT

We included 15 RCTs with 2015 participants. CBT was more effective than controls in fatigue (g = -0.52, 95%CI -0.69 to -0.35), perceived health, depression, and anxiety at post-treatment. At long-term follow-up the effects were maintained for fatigue and anxiety. Rates of non-completion (22%, 95%CI 3-71), drop-out (15%, 95%CI 9-25), and treatment refusal (7%, 95%CI 3-15) were relatively low, with a high average proportion of sessions completed. Total time of therapy moderated the effect on fatigue, while the number of sessions moderated the effect on perceived health. Fatigue severity influenced adherence.

CONCLUSION

The results indicate that CBT for CFS is effective in reducing fatigue, fatigue related impairment, and severity of depression and anxiety. Conclusions on efficacy at follow-ups are still limited. However, adherence is high in CBT. The results may help to inform clinical practice. Future research should focus on examining the maintenance of effects, while also emphasizing the importance of treatment acceptance.