Yoga, Health-Related Quality of Life and Mental Well-Being: A Re-analysis of a Meta-analysis using the Quality Effects Model.
J Gerontol A Biol Sci Med Sci. 2019 Dec 9. Epub 2019 Dec 9. PMID: 31814012
George A Kelley
BACKGROUND: Provide robust and practically relevant information regarding the association between yoga, health-related quality-of-life (HRQOL) and mental well-being (MWB) in older adults.
METHODS: Data were derived from a recent meta-analysis of 12 randomised controlled yoga trials representing 752 adults>60 years of age. Standardized mean difference effect sizes (ES's) were pooled using the recently developed quality effects model and 95% compatibility intervals (CI). Small-study effects were examined using the Doi plot and Luis Furuya-Kanamori (LFK) index. Sensitivity and cumulative meta-analyses were conducted as well as percentile improvement, number needed to treat (NNT), and number to benefit. The GRADE instrument was used to assess the strength of the evidence.
RESULTS: Yoga was associated with improvements in both HRQOL (ES = 0.51, 95% CI, 0.25-0.77, I2 =63.1%) and MWB (ES = 0.39, 95% CI, 0.15-0.63, I2 =56.2%). Percentile improvements were 19.5 for HRQOL and 15.3 for MWB while the NNT was 4 for HRQOL and 5 for MWB. An estimated 378,222 and 302,578 US yoga-practicing adults>65 years of age could potentially improve their HRQOL and MWB, respectively. Major asymmetry suggestive of small-study effects was observed for MWB but not HRQOL. Further examination for asymmetry revealed that greater improvements in MWB were associated with more (151 versus 68) minutes of yoga per week (p=0.007). Overall strength of evidence was considered"high"for HRQOL and"moderate"for MWB.
CONCLUSIONS: Yoga is associated with improvements in HRQOL and MWB among older adults, with approximately 150 minutes or more per week possibly optimal.