Bone mineral density and markers of bone turnover in boys with constitutional delay of growth and puberty

It has been suggested that poor growth in childhood or puberty might be a correctable determinant of osteoporosis. To assess the effect of the growth and puberty delay on bone metabolism, we measured bone mineral density (BMD) and markers of bone turnover in 41 boys with constitutional delay of growth and puberty. Total body (TB) and lumbar spine (LS) BMD were measured by dual-energy x-ray absorptiometry. Serum osteocalcin, total alkaline phosphatase, and urinary deoxypyridinoline cross-links as markers of bone turnover were evaluated. BMD was decreased by at least 1 sd in TB in 23 boys (56%) and in LS in 27 boys (66%). After adjustment of BMD for bone age, TB was decreased in 11 boys (27%) and LS in 13 boys (32%). Bone age and chronological age significantly correlated with areal and volumetric BMD. The significant increments of height, weight, TB, and LS BMD between the consecutive pubertal stages were reported. Mean alkaline phosphatase, osteocalcin, and deoxypyridinoline were within reference ranges and showed no differences between pubertal stages. In conclusion, in boys with constitutional delay of growth and puberty, bone turnover is normal, and BMD increases in a manner similar to healthy children.