Bone mineral density and vertebral fractures in men

In women, many studies indicate that the risk of vertebral fragility fractu res increases as bone mineral density (BMD) declines. In contrast, few stud ies are available for BMD and vertebral fractures in men. It is uncertain t hat the strength of the relationship between BMD and fractures is similar i n magnitude in middle-aged men and in postmenopausal women. In the present study, 200 men (mean age 54.7 years) with lumbar osteopenia (T-score <-1.5) were recruited to examine the relationships between spine BMD and hip BMD and the associations of BMD with vertebral fractures. Lumbar BMD was assess ed from L2 to L4, in the anteroposterior view, using dual-energy X-ray dens itometry. At the upper left femur, hip BMD was measured at five regions of interest: femoral neck, trochanter, intertrochanter, Ward's triangle and to tal hip. Spinal radiographs were analyzed independently by two trained inve stigators and vertebral fracture was defined as a reduction of at least 20% in the anterior, middle or posterior vertebral height. Spinal radiographs evidenced at least one vertebral crush fracture in 119 patients (59.5%). Th e results of logistic regression showed that age, femoral and spine BMDs we re significant predictors of the presence of a vertebral fracture. Odds rat ios for a decrease of 1 standard deviation ranged from 1.8 (1.3-2.8) for sp ine BMD to 2.3 (1.5-3.6) for total hip BMD. For multiple fractures odds rat ios ranged from 1.7 (1.1-2.5) for spine BMD to 2.6 (1.7-4.3) for total hip BMD. In all models, odds ratios were higher for hip BMD than for spine BMD, particularly in younger men, under 50 years. A T-score <-2.5 in the femur (total femoral site) was associated with a 2.7-fold increase in the risk of vertebral fracture while a T-score <-2.5 in the spine was associated with only a 2-fold increase in risk. This study confirms the strong association of age and BMD with vertebral fractures in middle-aged men, shows that the femoral area is the best site of BMD measurement and suggests that a low fe moral BMD could be considered as an index of severity in young men with lum bar osteopenia.