Effect of yoga on health-related outcomes in people at risk of fractures: a systematic review

We summarized the effects of yoga on health-related outcomes and adverse events in men and postmenopausal women ≥50 years-old at increased risk of fracture, to inform the updated Osteoporosis Canada clinical practice guidelines. Six databases were searched for observational studies, randomized controlled trials and case series. Certainty of evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluation handbook. Nine studies were included and reported using narrative syntheses due to the limited available evidence. Overall, the available evidence was of very low certainty. There was no effect of yoga on health-related quality of life in randomized trials. Effects on other health-related outcomes were mixed or not available in the literature. Five studies reported no adverse events directly related to the study intervention, and 2 studies did not report whether adverse events occurred. However, 2 case series reported vertebral fractures related to yoga participation, possibly due to excessive spinal flexion. Due to the limited and very low certainty evidence, guideline developers will need to draw indirect evidence from yoga studies among middle aged or older adults that are not at fracture risk. PROSPERO: CRD42019124898. Novelty: Evidence in general was of very low certainty. Yoga had no effect on health-related quality of life in randomized trials. Evidence was mixed or unavailable for other outcomes. Case studies reported yoga poses involving spinal flexion coincided with incidents of vertebral compression fracture among older adults with increased fracture risk.