High blood manganese tied to weaker bones

Blood manganese concentrations show a negative association with bone mineral density (BMD) and bone mineral content (BMC), suggesting that the metal may play a role in osteoporosis and osteopaenia, a recent study has found.

Drawing from the National Health and Nutrition Examination Survey, researchers enrolled 9,732 participants with available data. Dual-energy X-ray (DXA) absorptiometry was performed to measure participant BMC and BMD, while blood manganese levels were quantified using mass spectrometry.

A total of 3,682 total body DXA scans were available. In the fully adjusted model, patients in the highest vs lowest quartile of blood manganese saw significantly worse head BMD (β, –0.1984, 95 percent confidence interval [CI], –0.3017 to –0.0951; p<0.001; p_trend=0.0799) and BMC (β, –0.1628, 95 percent CI, –0.2706 to –0.055; p=0.003; p_trend=0.02).

A similar effect was reported for the left arm, left leg, pelvis, and trunk bone BMC and BMD.

The interaction between manganese and BMD and BMC was validated in total body analysis. The highest vs lowest quartile of blood manganese was significantly and inversely correlated with BMD (β, –0.2188, 95 percent CI, –0.3201 to –0.1175; p<0.001) and BMC (β, –0.3068, 95 percent CI, –0.3903 to –0.2233; p<0.001). For both parameters, the trend effect was significant (p<0.001).

“People exposed to manganese should be aware of the increased risk of osteopaenia or osteoporosis,” the researchers said, adding that while no standard thresholds have yet been established for tolerable intake and exposure limits or requirements, the present analysis could also help establish these standards.