The Function of Body Mass Index in the Older with Osteosarcopenia: A Systematic Review and Meta-analysis.

Background: Due to the aging population worldwide, diseases that frequently attack elderly people, such as sarcopenia and osteoporosis, are major public health issues.

Methods: This study used a systematic review and meta-analysis to examine the associations among body mass index (BMI), sarcopenia, and bone mineral density (BMD) in a group of adults older than 60 years. Eight studies with a total of 18,783 subjects were examined using a random effect model.

Results: In sarcopenia patients, total hip BMD (d=0.560; 95% confidence interval [CI], 0.438 to 0.681; P<0.01; I²=53.755%), femoral neck BMD (d=0.522; 95% CI, 0.423 to 0.621; P<0.01; I²=77.736%) and lumbar spine BMD (d=0.295; 95% CI, 0.111 to 0.478; P<0.01; I²=66.174%) were lower than in control subjects. Additionally, BMI (d=0.711; 95% CI, 0.456 to 0.996; P<0.01; I²=97.609%) correlated with the BMD of the total hip, femoral neck, and lumbar spine. That is, sarcopenia patients with low BMD levels in the total hip, femoral neck, and lumbar spine also had low fat levels. Thus, sarcopenia patients with low BMD in the total hip, femoral neck and lumbar spine and low BMI could have a higher than average risk of osteosarcopenia. No sex effects were significant (P>0.05) for any variable.

Conclusion: BMI could be a key point in osteosarcopenia, suggesting that a low body weight could be facilitate the transition from sarcopenia to osteosarcopenia.