Abstract
Title: Exploring the effects of yoga for generalised anxiety disorder (GAD), with or without comorbidity: A systematic review of randomised and non-randomised controlled trials. Background: Yoga is a philosophical system and a spiritual practice originating from a five-thousand-year-old Eastern discipline and is recommended as a therapy for a variety of medical conditions. Given the high prevalence of GAD and the deleterious consequences it has on the patient, effective treatments are considered crucial. Objective: To systematically assess and meta-analyse the effects of yoga interventions in reducing anxiety in patients with GAD. Research question: How may yoga alleviate anxiety amongst patients with GAD, with or without comorbidities? Methods: A comprehensive systematic literature search was completed using search engine databases, including MedLine® ovid and PsycINFO® ovid during a period from September 2019 to April 2020. Risk of bias was assessed using adapted versions of the Cochrane Collaboration tools. A meta-analysis was conducted using the random-effect model to obtain standardised mean differences with 95 % confidence intervals. Results: Of 565 studies identified through the literature search, four studies met inclusion criteria (N = 704). All studies were assessed at serious risk of bias. Except for one study (Chad-Friedman et al., 2019), all reported significant results favouring the yoga intervention. A meta-analysis revealed evidence for large short-term effects of yoga on anxiety compared with treatment-as-usual and wait-list control (SMD = -0.92, 95 % CI = -1.28, -0.56, p < 0.001). Results suggest that yoga reduces anxiety symptoms for GAD patients. Conclusion: The limited number of included studies and their low methodological quality prevents any firm conclusions from being drawn. High-quality studies are required to determine the effect of yoga on GAD.