title: BMI percentile-for-age overestimates adiposity in early compared with late maturing pubertal children.
abstract: OBJECTIVE
  Early pubertal timing is consistently associated with increased BMI percentile-for-age in pubertal girls, while data in boys are more ambiguous. However, higher BMI percentile-for-age may be a result of the earlier puberty per se rather than vice versa. The aim was to evaluate markers of adiposity in relation to pubertal timing and reproductive hormone levels in healthy pubertal boys and girls.
  
  
  METHODS
  Population-based cross-sectional study (The Copenhagen Puberty Study). Eight-hundred and two healthy Caucasian children and adolescents (486 girls) aged 8.5-16.5 years participated. BMI and bioelectric impedance analyses (BIA) were used to estimate adiposity. Clinical pubertal markers (Tanner stages and testicular volume) were evaluated. LH, FSH, estradiol, testosterone, SHBG and IGF1 levels were determined by immunoassays.
  
  
  RESULTS
  In all age groups, higher BMI (all 1 year age-groups, P ≤ 0.041) was found with early compared with late maturation, despite similar BIA-estimated body fat percentage (BIA-BF%). Neither BMI nor BIA-BF% differed for a given stage of maturation. BMI percentile-for-age and prevalence of overweight/obesity were higher in the early compared with late matured pubertal children (all P ≤ 0.038), despite similar BIA-BF%. Pubertal girls with BIA-BF >29% had significantly lower LH and FSH levels compared with normal-weight girls (P ≤ 0.041).
  
  
  CONCLUSIONS
  Early maturational timing was not associated with higher adiposity for a given stage of puberty. Using BMI percentile-for-age overestimated the degree of adiposity in early pubertal compared with late pubertal children.
authors.affiliation: Department of Growth and ReproductionGR-5064, Copenhagen University Hospital, Blegdamsvej 9, DK-2100 Copenhagen, Denmark kasparsoerensen@gmail.com.
authors.forename: Kaspar
authors.initials: K
authors.lastname: Sørensen
authors.affiliation: Department of Growth and ReproductionGR-5064, Copenhagen University Hospital, Blegdamsvej 9, DK-2100 Copenhagen, Denmark.
authors.forename: Anders
authors.initials: A
authors.lastname: Juul
mesh_terms: D050154:Adiposity / Q000502:physiology*; D000293:Adolescent; D000367:Age Factors; D015992:Body Mass Index; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D003718:Denmark / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D009765:Obesity / Q000175:diagnosis / Q000453:epidemiology / Q000378:metabolism; D050177:Overweight / Q000175:diagnosis / Q000453:epidemiology / Q000378:metabolism; D011629:Puberty, Precocious / Q000175:diagnosis / Q000453:epidemiology / Q000378:metabolism; D012741:Sexual Maturation / Q000502:physiology*; D055815:Young Adult