Association of overweight and obesity with vertebral fractures: a systematic review and meta-analysis

INTRODUCTION: Over the past decade, there has been increasing interest in exploring the relationship between overweight, obesity and vertebral fractures. Nonetheless, available data from studies on the relationship between overweight, obesity and vertebral fractures remains controversial. EVIDENCE ACQUISITION: A systematic search was performed in the PubMed and Cochrane Library databases. We selected relevant literature by using these keywords: fracture, vertebral fracture, vertebral compression fracture, overweight, obese, obesity. The retrieval mainly collected publicly published observational studies on the correlation between overweight, obesity and vertebral fractures, excluding the literature that did not meet the inclusion criteria. Meta -analysis for the data extracted from all the included literatures was performed by STATA 12.0 (StataCorp LLC, College Station, TX, USA) to summarize test performance with forest plots and assess the heterogeneity. EVIDENCE SYNTHESIS: Ten studies, including 1,024,181 subjects satisfied the predefined eligibility criteria. The results showed that the overweight (25.0 <= Body Mass Index [BMI] <= 29.9 kg/m(2)) and obesity (BMI>30.0kg/m(2)) were associated with a decreased risk of vertebral fractures, respectively. The pooled RR is 0.86 (95% CI: 0.79, 0.95) and 0.81(95% CI:0.74-0.90) with no evidence of statistical heterogeneity. However, the relationship between overweight/ obesity (BMI>25 kg/m(2)) and vertebral fractures is not statistically significant. CONCLUSIONS: This study showed that overweight and obesity might decrease the risk of vertebral fractures, respectively. However, we did not observe a significant association between overweight/obesity (BMI>25 kg/m(2)) and vertebral fractures.