title: Gender difference in the relationship between passive smoking exposure and HDL-cholesterol levels in late adolescence.
abstract: BACKGROUND
  High-density lipoprotein-cholesterol (HDL-C) levels are influenced by gender and by genetic and environmental factors. We aimed to assess the impact of passive smoking exposure since birth on HDL-C levels of nonsmoking adolescents at age 17 years and to determine whether there was a gender difference in the relationship between smoking exposure and HDL-C.
  
  
  METHODS
  A total of 804 nonsmoking adolescents with biochemical, anthropometric, and lifestyle data from a cohort of 1754 adolescents (mean age, 17 ± 0.25 y) of the Western Australian Pregnancy Cohort (Raine) Study had data of maternal smoking during pregnancy and smoking exposure in the household over 17 years. HDL-C was analyzed using multivariable linear regression, with adjustment for early-life, adiposity, and current lifestyle confounders.
  
  
  RESULTS
  HDL-C levels were significantly lower in girls exposed to passive smoking compared to those not exposed (regression coefficient b = -0.09 [95% confidence interval, -0.15, -0.03]); this was not observed in boys (b = 0.02 [95% confidence interval, -0.04, 0.08]), with a significant sex interaction P = .009. The effects of passive smoking in girls persisted after adjusting for oral contraceptive use.
  
  
  CONCLUSIONS
  This study has shown a gender difference in the relationship between passive smoking exposure since birth and HDL-C in late adolescence. Exposure to passive smoking in girls could have adverse consequences on their risk of cardiovascular disease in adulthood. These findings reinforce the need for future public health measures to reduce children's exposure to passive smoking.
authors: Royal Perth Hospital Unit, School of Medicine and Pharmacology, University of Western Australia, Perth, Western Australia 6000, Australia. cleha@meddent.uwa.edu.au
authors: Chi
authors: C
authors: Le-Ha
authors: Lawrence J
authors: LJ
authors: Beilin
authors: Sally
authors: S
authors: Burrows
authors: Rae-Chi
authors: RC
authors: Huang
authors: Wendy H
authors: WH
authors: Oddy
authors: Beth
authors: B
authors: Hands
authors: Trevor A
authors: TA
authors: Mori
mesh_terms: D050154:Adiposity; D000293:Adolescent; D001724:Birth Weight; D001942:Breast Feeding; D002318:Cardiovascular Diseases / Q000453:epidemiology* / Q000209:etiology*; D008076:Cholesterol, HDL / Q000097:blood*; D015331:Cohort Studies; D005191:Family Characteristics; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008019:Life Style; D008137:Longitudinal Studies; D008297:Male; D008425:Maternal Behavior; D008954:Models, Biological; D012306:Risk; D012727:Sex Characteristics; D014028:Tobacco Smoke Pollution; D014904:Western Australia / Q000453:epidemiology
chemical_list: D008076:Cholesterol, HDL; D014028:Tobacco Smoke Pollution