The Osteoporosis Society of Canada (OSC) believes that pediatric osteoporosis is an emerging problem in this country. However, the OSC guidelines1 were developed primarily to address osteoporosis in adults; accordingly, they should not be used for children, except for the well-supported guidelines on physical activity and nutrition.
The paucity of recommendations specific to children in the recently published guidelines1 was unfortunate, yet justifiable. In contrast to the situation for adults, few high-quality osteoporosis trials involving children have been conducted, particularly with regard to treatment. This scarcity of trials makes it difficult or impossible to develop evidenced-based guidelines. Nonetheless, it is recognized that severely afflicted children must be treated. Because of the complexity and predominantly secondary causes of pediatric osteoporosis, its diagnosis and treatment should be reserved for specialists who keep abreast of this rapidly evolving field and who must combine sound clinical judgement with the limited evidence that is available.
The diagnosis of osteoporosis in children is complicated and unclear. At the root of the problem is the size dependency of bone mineral density data obtained by dual-energy x-ray absorptiometry. The density of smaller bones is systemically underestimated and that of larger bones is overestimated, which causes errors in interpretation when comparing children's values with adult norms, when comparing one child with another and when comparing values obtained during growth. Many methods have been proposed for dealing with this size dependency,2,3,4,5,6,7,8,9 but none are in regular clinical use, nor have any been related to fracture risk. Canadian pediatric bone mineral density10 and bone mineral content11 norms are available, yet their proper use is unknown.
The roots of osteoporosis lie in childhood; as much bone is laid down during puberty as is lost in all later life.11 Thus, any perturbation of normal bone accrual during growth (related to alcohol, smoking, bone-robbing medications, or lack of adequate physical activity or calcium) will have devastating effects on skeletal health in later years. The key is prevention.
More quality trials in the diagnosis, prevention and treatment of pediatric osteoporosis are sorely needed.
Jacques P. Brown Chair, Scientific Advisory Council Osteoporosis Society of Canada Toronto, Ont.