Effects of Isoflavone Interventions on Bone Metabolism in Perimenopausal and Postmenopausal Women: An Umbrella Review of Meta-Analyses of Randomized Controlled Trials

Abstract

Objective

Previous meta-analyses have investigated the effects of isoflavones on bone metabolism in perimenopausal or postmenopausal women. However, there were still conflicting results. Thereby, this umbrella review assessed the existing meta-analysis evidence of the effects of isoflavone interventions on bone metabolism in perimenopausal and postmenopausal women.

Methods

This study was conducted following the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. From the inception until August 24, 2023, PubMed, Embase, Cochrane, and Web of Science databases were searched to identify meta-analyses of randomized controlled trials. The outcomes included bone mineral densities (BMDs), and bone turnover markers of osteocalcin, bone-specific alkaline phosphatase, pyridinoline, deoxypyridinoline, Procollagen Type 1 N-Terminal Propeptide, and C-telopeptide of Type 1 Collagen. The random-effects model was used to recalculate the extracted effect sizes. Mean difference (MD) was used as a summary effect measure.

Results

Ten meta-analyses of randomized controlled trials were included. The isoflavone intervention was associated with increased BMDs in lumbar spine (MD: 11.50 mg/cm², 95% confidence interval (CI): 6.46 to 16.55), femoral neck (MD: 2.03%, 95% CI: 0.57 to 3.50), and top hip (MD: 0.31%, 95% CI: 0.03 to 0.59) in perimenopausal and postmenopausal women.

Conclusion

Our findings indicate that isoflavone interventions have the potential to improve BMD at different bone sites, including the lumbar spine, femoral neck, and total hip in perimenopausal and postmenopausal women. Isoflavone may be considered a complementary option in the bone loss of perimenopausal and postmenopausal women.