Association between Metabolic Syndrome and Bone Mineral Density--Data from the Berlin Aging Study II (BASE-II)

Decreased bone mineral density (BMD) has been linked to metabolic disorders, such as type 2 diabetes. However, results regarding the metabolic syndrome (MetS), a cluster of at least 3 of 5 cardiovascular risk parameters with potentially contradictory effects on BMD are still inconclusive.

We investigated the effect of MetS and its single parameters on BMD at 3 sites in community-dwelling older subjects.

1,402 subjects (51.1% female, 68 ± 4 years old) from the Berlin Aging Study II (BASE-II) were included. MetS was defined as suggested by IDF/NHLBI/AHA. Insulin resistance (IR) was assessed by the homeostasis model of IR. BMD (lumbar spine, femur neck, hip) and trunk fat were measured by dual-energy X-ray absorptiometry. Osteoporosis was defined by a T score of ≤-2.5.

MetS was present in 29.6% of women and 41.7% of men. In regression models, we observed a positive association of MetS with the BMD of the lumbar spine (p = 0.005) and hip (p = 0.028) in women even after adjustment for risk factors, but no effect of the single parameters apart from IR. In contrast, there was no association between MetS and BMD in men. However, higher trunk fat and higher waist circumference were associated with lower levels of BMD in men with or without MetS (p < 0.05).

We obtained different results in men and women. In women, the positive though slight effect of MetS on BMD could not be explained by single MetS components apart from IR. In men, central obesity was negatively associated with BMD, suggesting that the metabolic effects driven by visceral fat have a negative impact.