Meta-analysis finds sex- and site-specific BMD associations with metabolic syndrome

Researchers searched several databases for cross-sectional studies published within the preceding 10 years that reported lumbar spine, femoral neck or total hip BMD in adults with and without metabolic syndrome. Twelve studies were included in the synthesis, with populations from multiple regions. The analysis used random-effects models and included subgroup analyses by sex and menopausal status. Overall study quality was assessed as having low to moderate risk of bias.

Men with metabolic syndrome had higher BMD at the lumbar spine (p=0.03) and femoral neck (p=0.003), with a significant pooled effect across skeletal sites (Z=5.57, p<0.00001). No significant association with overall BMD was found in women. In subgroup analyses, postmenopausal women without metabolic syndrome had higher femoral neck and lumbar spine BMD than those with the syndrome (p=0.03 and p=0.04, respectively). Sensitivity analysis found a larger pooled lumbar-spine effect in women in studies with assessment periods of one year or less.

These observational findings suggest associations may vary by sex and skeletal site, but do not establish causality or show that metabolic syndrome should alter bone-health management. The authors note that higher-quality research is needed to clarify clinical implications.