Obesity and risk of fracture in postmenopausal women: a meta-analysis of cohort studies

BACKGROUND: Obesity is associated with an increased risk of fracture in adults, but is unclear in postmenopausal women. We aim to determine the association of obesity with the risk of fracture in postmenopausal women. METHODS: PubMed, EMBASE, Cochrane Library and Web of Science were searched up to 11 April 2022 for cohort studies. And the included studies regarding the relationship between obesity with all cause of fracture in postmenopausal women were included in our meta-analysis. Data were screened and extracted independently by two reviewers. The relative risks (RR) were estimated using a random-effects model. Between-study heterogeneity was assessed using Cochran’s Q and I(2) statistics. RESULTS: Eight cohort studies comprising 671,532 postmenopausal women and 40,172 fractures were included. Overall, the pooling analysis shows that obesity in postmenopausal women is associated with an increased risk of all-cause fracture (relative ratio (RR) = 1.18; 95% confidence interval (CI):1.09–1.28, I(2) = 86.3%, p = .000). Sub-analyses for each site of fracture indicate that obesity was associated with an increased risk of vertebral fracture in postmenopausal women (RR = 1.154, 95% CI: 1.020–1.305, I(2) = 94.5%, p = .023), but reduced the risk of pelvic fracture (RR = 0.575, 95% CI:0.470–0.702, I(2) = 0.0%, p = .000). There is no statistically significant difference in the risk of hip and humerus fractures associated with obesity in postmenopausal women. CONCLUSION: Obesity is associated with an increased risk of all-cause and vertebral fractures in postmenopausal women, but is a protective factor for pelvic fractures. Our findings suggest that postmenopausal women who regulate their weight might lower their risk of fractures.Registration:: KEY MESSAGES: Obesity is associated with an increased risk of all-cause and vertebral fractures in postmenopausal women. Obesity maybe a protective factor for pelvic fractures in postmenopausal women. Postmenopausal women should regulate their weight to prevent fractures.