title: Puberty-associated differences in total cholesterol and triglyceride levels according to sex in French children aged 10-13 years.
abstract: OBJECTIVE
  To assess the relationships between lipid levels and sexual maturity, independently of age-related differences, and to investigate possible differences related to sexual maturity across the percentiles of the lipid distributions.
  
  
  METHODS
  Fasting serum total cholesterol and triglyceride concentrations were measured in 6577 boys and 6605 girls, aged from 10 to 13 years, with different Tanner stages. The total cholesterol and triglyceride mean and percentile levels were estimated according to age and Tanner stage by ordinary least squares and percentile regression models, separately in both sexes.
  
  
  RESULTS
  In boys and girls, total cholesterol levels were significantly associated with pubertal stage after controlling for age. At age 12, the estimated mean levels in boys varied from 4.82 mmol/L for Tanner 1 to 4.41 for Tanner 5. The corresponding values were 5.05 and 4.62 mmol/L in girls, for whom the association with maturity was stronger in the upper than in the lower percentiles (p < 0.0001); between the extreme Tanner stages, the 95th percentiles of total cholesterol differed by 0.80 mmol/L, in comparison to 0.19 mmol/L for the 5th percentiles. Therefore, 1. 8% of girls and 0.7% of boys were classified differently whether Tanner stage was used or not to assess hypercholesterolemia (concentrations in the upper 5% of the distributions). Triglycerides were positively related to sexual maturity independently of age, but the discrepancies between classifications were lower; 1.1% in girls and 0.4% in boys.
  
  
  CONCLUSIONS
  Our findings emphasize the importance of sexual maturity, even for a given age, for interpreting lipid levels in children.
authors.affiliation: National Institute of Health and Medical Research (INSERM) Unit 258, Faculty of Medicine Paris-Sud, Villejuif, France.
authors.forename: S
authors.initials: S
authors.lastname: Bertrais
authors.forename: B
authors.initials: B
authors.lastname: Balkau
authors.forename: M A
authors.initials: MA
authors.lastname: Charles
authors.forename: S
authors.initials: S
authors.lastname: Vol
authors.forename: C
authors.initials: C
authors.lastname: Calvet
authors.forename: J
authors.initials: J
authors.lastname: Tichet
authors.forename: E
authors.initials: E
authors.lastname: Eschwege
mesh_terms: D000293:Adolescent; D000367:Age Factors; D002648:Child; D002784:Cholesterol / Q000097:blood*; D005260:Female; D005602:France / Q000453:epidemiology; D006801:Humans; D008297:Male; D011627:Puberty / Q000502:physiology*; D012727:Sex Characteristics; D014280:Triglycerides / Q000097:blood*
chemical_list: D014280:Triglycerides; D002784:Cholesterol