AUTHOR=Zheng Yijin , Liang Jianping , Zeng Ding , Tan Weiqing , Yang Lun , Lu Shuang , Yao Wanwen , Yang Yi , Liu Li 

TITLE=Association of body composition with pubertal timing in children and adolescents from Guangzhou, China

JOURNAL=Frontiers in Public Health

VOLUME=Volume 10 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/public-health/articles/10.3389/fpubh.2022.943886

DOI=10.3389/fpubh.2022.943886

ISSN=2296-2565

ABSTRACT=Objective: An on-going debate surrounds the relationship between body composition and pubertal timing, in particular for boys. This cross-sectional study aimed to investigate the association of body composition with pubertal timing among children and adolescents. 
Methods: A total of 1493 boys and 1261 girls entered puberty were enrolled from Guangzhou, China. Tanner stages were evaluated by examination of breast development for girls and testicular volume for boys. Fat mass (FM) and fat-free mass (FFM) were determined by bioelectrical impedance analysis. Parameters for body composition were transformed into age-and gender-specific Z-scores. The association of body composition with pubertal timing was examined using multinomial logistic regression with inverse probability weighting (IPW) based on propensity score.
Results: For boys, IPW analysis showed Z-scores of body fat percentage (BF%) and FM index (FMI) were negatively associated with early puberty (OR=0.75, 95% CI=0.64-0.87; OR=0.74, 95% CI=0.63-0.88). As for girls, in contrast to boys, positive associations were seen of BF% and FMI with early puberty (OR=1.39, 95% CI=1.19-1.64; OR=1.59, 95% CI=1.33-1.90). With respect to appendicular skeletal muscle mass index (ASMI), there was a positive association with early puberty and a negative one with late puberty in boys (OR=1.26, 95% CI=1.07-1.49; OR=0.82, 95% CI=0.69-0.99).
Conclusions: There is a positive association of FM with early puberty for girls while negative for boys. FFM yields a positive association with early puberty and a negative one with late puberty in boys, but not in girls. Our findings highlight the gender differences in the connection between body composition and pubertal onset.