Low sex hormone levels increase fracture risk in older men

Low serum levels of testosterone and estradiol (E₂) are associated with an increased osteoporotic fracture risk in community dwelling men older than 60 years, although only the effect of testosterone is associated independent of other established risk factors. Measurement of serum testosterone may provide additional clinical information for fracture risk assessment in these men.

Meier and colleagues prospectively examined the relationship between serum levels of testosterone and E₂ and future fracture risk in 609 men (mean age, 72.6 years). They assessed lifestyle factors, calcium intake, and bone mineral density (BMD); determined the incidence of low-trauma fracture; and measured serum testosterone and E₂ levels by tandem mass spectrometry.

During follow-up, the incidence of fracture was 2.7-fold higher in men 70 years or older than in younger men. The risk of fracture was increased significantly in men with lower testosterone levels. Serum testosterone and serum E₂ levels were associated with overall fracture risk after adjustment for sex hormone–binding globulin. After further adjustment for major risk factors (eg, age,weight or BMD, and fracture history), a lower testosterone level was still associated with increased risk of fracture.

The authors noted that their findings should not be interpreted as an indication of a causal relationship.