Medicinal Herbs for Managing Fatigue Symptoms in Patients with Idiopathic Chronic Fatigue: A PRISMA Compliant Updated Systematic Review and Meta-Analysis of Randomized Controlled Trials Based on the GRADE Approach

Abstract Introduction Idiopathic chronic fatigue is a common condition that has a profound impact on daily life. Given the absence of a clearly defined guideline for conventional treatment, herbal medicines are often the preferred interventions in these patients. In this updated systematic review, we evaluate the evidence for the efficacy of herbal medicines in patients with idiopathic chronic fatigue using the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) approach. Method Core electronic databases were searched up to May 2019. The review included RCTs that compared herbal medicines with placebo, waitlist, or conventional drug treatments. Risk of bias was assessed to evaluate the methodological quality of the individual studies and a meta-analysis was performed to calculate summary effect estimates based on a random effects model. The certainty of the evidence was evaluated by GRADE assessment. Results Twenty-two RCTs (1819 patients) were eligible for inclusion in the review. The standardized mean difference on the fatigue symptom scale was -1.19 (95% confidence interval -1.45, -0.92, I2 = 85%) in favor of herbal medicines. Only a few studies reported adverse events, all of which were mild and self-limiting. The certainty of evidence level for the effect of herbal medicines was found to be very low by GRADE assessment. Conclusion Even though our summary effects estimate suggests a potential benefit of herbal medicines for managing fatigue symptoms in chronic fatigue syndrome, the evidence needs to be updated by rigorous clinical trials with detailed reporting of adverse events in the future.