Rate of bone loss is greater in young Mexican American men than women: The San Antonio Family Osteoporosis Study

Abstract

Little is known about the progression of bone loss during young adulthood and whether it differs between men and women. As part of the San Antonio Family Osteoporosis Study we tested whether bone mineral density (BMD) changed over time in men or women, and whether the rate of BMD change differed between the sexes. BMD of the proximal femur, spine, radius, and whole body was measured in 115 men and 202 pre-menopausal women (ages 25 to 45 years; Mexican American ancestry) by dual-energy x-ray absorptiometry at two time points (5.6 years apart), from which annual percent change-in-BMD was calculated. Likelihood-based methods were used to test whether change-in-BMD differs from zero or differs between men and women. In men, percent change-in-BMD was significantly greater than zero for the 1/3 radius (i.e. indicating a gain of BMD; Bonferroniadjusted p < 0.01), less than zero for the femoral neck, lumbar spine, ultradistal radius, and whole body (i.e. indicating a loss of BMD; p < 0.01 for all), and not different than zero for the total hip (p = 0.24). In women, percent change-in-BMD was greater than zero for the total hip, 1/3 radius, and whole body (p < 0.01 for all), less than zero for the ultradistal radius (p < 0.01), and not significantly different than zero for the femoral neck and lumbar spine (p = 1.0 for both). For all skeletal sites, men experienced greater decrease in BMD (or less increase in BMD) than women; this result was observed both with and without adjustment for age, BMI, and change-in-BMI (p < 0.05 for all). These results suggest that significant bone loss occurs at some skeletal sites in young men and women, and that loss of BMD is occurring significantly faster, or gain of BMD is occurring significantly slower, in young men compared to young women.

Effectiveness of resistance training or jumping-exercise to increase bone mineral density in men with low bone mass: A 12-month randomized, clinical trial

“…The biological and clinical significance of these results can be appreciated only if one considers that bone loss occurs with normal aging. Young adult and middle-aged men lose BMD at rates of ~0.4–1.5% per year [42–44]. The results are also important because they suggest that a time-efficient (2–3 days per week) intervention of either RT or JUMP can improve BMD in otherwise healthy men.…”

Cortical Bone Model With a Microcrack Under Tensile Loading

“…Experimental method is one of the most frequently used methods in the study of osteonal cortical bone structures and fracture analysis [8,[22][23][24][25][26][27], the results demonstrate that the fracture properties of cortical bone are substantially anisotropic. Finite element method is used in the computational study of cortical bone fracture mechanics [7-9, 11, 25, 28], the results indicate that material properties and morphological parameters of the microstructure greatly influence the bone's fracture behavior.…”