Effect of Adjusting for Tanner Stage Age on Prevalence of Short and Tall Stature of Youths in the United States.

OBJECTIVE

To evaluate the extent to which pubertal timing alters the classification of extremes of attained stature across race-ethnicity groups of youths in the US.

STUDY DESIGN

We performed analyses of height and Tanner staging data of 3206 cross-sectional national sample of youths ages 8-18 years (53% male, n = 1606), 72% of whom were non-Hispanic white, 9% Mexican American, and 19% non-Hispanic black . Specialized growth models were used to derive Tanner-stage-age-adjusted z scores (TSA). The prevalence of shortness (<-1SD) and tallness (≥+1SD) status was quantified using TSA.

RESULTS

Highly variable patterns of prevalence of shortness and tallness via chronologic age height z score (CA) were observed in results stratified by race-ethnicity and sex. Tallness CA prevalence was high among non-Hispanic white and non-Hispanic black male youths relative to Mexican American (40.0%-43.3% vs 20.5%) with a similar pattern in female youths. In both sexes, this pattern was eliminated with TSA, with Mexican American youth becoming statistically not different from their non-Hispanic white and non-Hispanic black peers.

CONCLUSIONS

Differences in timing of puberty between race-ethnicity groups affects estimated prevalence of shortness and tallness of attained height that remains uncaptured with CA. Adjustment for pubertal development might help isolate crucial determinants of attained stature and other aspects of body composition that may be most responsive to intervention programs in populations. The curves developed by adjusting for pubertal status may help the clinician avoid misclassification of children with early and late pubertal development.