Longitudinal growth of stature in boys according to age and puberty: Prediction of adult stature from the age of 13 years.

Abstract

The purpose of this study was to cross-validate and demonstrate how adult stature can be predicted in 13-year-old teenager's boys by using a new reference specific growth curve obtained from chronological age and maturity. Stature measurements of 125 boys aged from 12 to 17.5 years were obtained over a period of five consecutive years. The maturity was based on the age of peak height velocity (APHV). An assessment of secondary pubertal stages using a simplification of the Tanner stages was also carried out. We found a connection between the secondary pubertal stage and the APHV. We carried out a prediction of the adult stature of 67 teenagers aged from 160 and 164 months. Significant differences between APHV enabled us to classify the adolescents into three categories according to their biological maturity: 19% of adolescents with advanced puberty, 62% with standard puberty and 19% with delayed puberty. The mean growth curves were used to predict the adult stature of 67 individuals with a good accuracy (±3cm). The mean differences between predicted and real adult stature are -0.11 cm with 95% limits of agreement of [-3.2; + 2.8cm]. The new stature growth curves developed from age and maturation enables us to accurately track individual growth kinetics.