Longitudinal growth and height velocity of Japanese children with Down's syndrome

AIM: To determine the natural growth pattern of Japanese children with Down's syndrome. METHODS: Longitudinal height data of 85 patients (43 males, 42 females) from birth to final height were analyzed. Based on these data, semi-longitudinal standard growth curves and height velocity curves for Down's syndrome were drawn. RESULTS: The means +/- SD of final height of males and females with Down's syndrome were 153.2 +/- 5.6 and 141.9 +/- 4.2 cm, respectively. They were -3.0 SD and -2.8 SD for Japanese standards. Mean peak height velocities were 8.9 and 7.5 cm y(-1), and the ages at peak height velocity were 11.6 and 10.2 y for males and females, respectively. CONCLUSION: The mean height of patients with Down's syndrome was around -2 SD for normal children before puberty. Their pubertal growth spurt starts about 1 y earlier and their peak height velocity was about 1.3-1.4 cm shorter than for normal children.