American Society for Bone and Mineral Research, Oct. 12-15, 2012Last Updated: October 19, 2012.
The annual meeting of the American Society for Bone and Mineral Research was held from Oct. 12 to 15 in Minneapolis and attracted approximately 4,000 participants from around the world, including basic research scientists and clinical investigators in bone and mineral metabolism as well as physicians and other health care practitioners. The conference focused on the latest advances in bone and mineral research as well as the translation of research into clinical practice.
In one study, Joan Lappe, Ph.D., R.N., of the Creighton University Osteoporosis Research Center in Omaha, Neb., and colleagues evaluated whether the stage of sexual maturation plays a role in determining the relationship between calcium intake and physical activity and bone mass accrual.
"Based on our data, we estimate that, for each extra 3.5 hours per week (half hour per day) of weight-bearing physical activity, girls would increase their bone mass by about 2 percent per year. If these girls maintained that extra activity for five years of growth, for example, they would gain an extra 10 percent bone mass compared to girls who did not add that extra activity. Ten percent is about one dual-energy X-ray absorptiometry T-score. In adults, one additional T-score decreases the risk of osteoporotic fracture 2.5-fold. Boys would increase their bone mass by about 1 to 1.5 percent per year," Lappe said. "On physical activity questionnaires such as we used, kids overestimate the amount of activity they get. Thus, the effects of exercise are likely greater than we found, meaning that with a little added exercise, kids can really improve their bone health."
The investigators also found that, among non-black boys and girls, calcium intake from food increased bone mass accrual.
"This suggests that not all kids are getting the amount of calcium they need for healthy bones," Lappe said. "Adding even one glass of milk per day would increase accrual by 1 to 2 percent per year."
Overall, Lappe concludes that adding a little extra physical activity and dietary calcium intake can make a significant improvement in bone mass accrual in children and adolescents.
In another study, Robin Daly, Ph.D., of Deakin University in Melbourne, Australia, and colleagues found that a specialist-led physical education program implemented during elementary school improved physical fitness, muscle mass, and bone health, particularly in girls, compared to standard physical education classes conducted by classroom teachers.
"The findings from this four-year school-based physical activity intervention indicate that children (particularly girls) who received specialist-led physical education twice weekly (plus one general/standard classroom teacher-led physical education session, for a total of 150 min/week) during elementary school experienced greater improvements in physical fitness and performance, lean tissue mass, and bone structure, compared to those who received the standard 150 minutes of physical education led by the classroom teacher," Daly said. "These findings suggest that the introduction of trained physical educators into primary schools who introduce programs focusing on strength, balance, and posture through games and activities designed to promote moderate-to-vigorous physical activity may represent an effective strategy to improve health outcomes in young children, without the need to increase the total time allocated to physical education."
Tobias de Villiers, Ph.D., of Mediclinic Panorama in Cape Town, South Africa, and colleagues evaluated the use of a new orally-active cathepsin K inhibitor, odanacatib, to further improve bone mineral density after treatment with alendronate for an average of 5.5 years.
"After two years of treatment in women previously exposed to alendronate, treatment with odanacatib further increased bone mineral density significantly, by 2.6 percent at the femur neck, compared to women taking placebo," de Villiers said. "Odanacatib thus offers an exciting option for women who desire further increase in bone mineral density after three to five years on alendronate."
In the FREEDOM Study Extension, Jacques Brown, Ph.D., of the CHUQ Research Centre at Laval University in Quebec, and colleagues evaluated the effects of five years of denosumab on bone histology and histomorphometry. The investigators assessed the effects of denosumab on remodeling at the tissue level using transiliac crest bone biopsy.
"Denosumab treatment through five years results in normal bone quality with reduced bone turnover, consistent with its mechanism of action," the authors concluded.
In the Iowa Bone Development study, Shelby Francis, Ph.D., of the University of Iowa in Iowa City, and colleagues assessed the sustained effects of physical activity on bone health among young children and adolescents. The investigators evaluated data on body size, somatic maturity, moderate vigorous physical activity, and vigorous physical activity among 156 boys and 170 girls who had clinical exams at ages 5, 8, 11, 13, and 15 years.
"Everyday childhood activity provides bone benefits that can be sustained into adolescence," the authors concluded. "These results, especially in boys, suggest that bone strengthening physical activity programming should begin early in childhood."