title: Associations between pre-pregnancy obesity and asthma symptoms in adolescents.
abstract: BACKGROUND
  The high prevalence of children's asthma symptoms, worldwide, is unexplained. We examined the relation between maternal pre-pregnancy weight and body mass index (BMI), and asthma symptoms in adolescents.
  
  
  METHODS
  Data from 6945 adolescents born within the Northern Finland Birth Cohort 1986 were used. Prospective antenatal and birth outcome data, including maternal pre-pregnancy weight and BMI, and asthma symptoms in adolescent offspring at age 15-16 years, were employed. Logistic regression analyses were performed to examine the associations between relevant prenatal factors and asthma symptoms during adolescence.
  
  
  RESULTS
  Current wheeze (within the past year) was reported by 10.6% of adolescents, and physician-diagnosed asthma by 6.0%. High maternal pre-pregnancy BMI was a significant predictor of wheeze in the adolescents (increase per kilogram per square metre unit; 2.7%, 95% CI 0.9 to 4.4 for ever wheeze; 3.5%, 95% CI 1.3 to 5.8 for current wheeze), and adjusting for potential confounders further increased the risk (2.8%, 95% CI 0.5 to 5.1; 4.7%, 95% CI 1.9 to 7.7, respectively). High maternal pre-pregnancy weight, in the top tertile, also significantly increased the odds of current wheeze in the adolescent by 20% (95% CI 4 to 39), and adjusting for potential confounders further increased the risk (OR=1.52, 95% CI 1.19 to 1.95). Results were similar for current asthma. Furthermore, these significant associations were observed only among adolescents without parental history of atopy but not among those with parental history of atopy.
  
  
  CONCLUSIONS
  The association demonstrated here between maternal pre-pregnancy overweight and obesity, and asthma symptoms in adolescents suggests that increase in asthma may be partly related to the rapid rise in obesity in recent years.
authors.affiliation: Department of Epidemiology and Biostatistics, Imperial College London, Norfolk Place, London W2 1PG, UK.
authors.forename: Swatee P
authors.initials: SP
authors.lastname: Patel
authors.forename: Alina
authors.initials: A
authors.lastname: Rodriguez
authors.forename: Mark P
authors.initials: MP
authors.lastname: Little
authors.forename: Paul
authors.initials: P
authors.lastname: Elliott
authors.forename: Juha
authors.initials: J
authors.lastname: Pekkanen
authors.forename: Anna-Liisa
authors.initials: AL
authors.lastname: Hartikainen
authors.forename: Anneli
authors.initials: A
authors.lastname: Pouta
authors.forename: Jaana
authors.initials: J
authors.lastname: Laitinen
authors.forename: Terttu
authors.initials: T
authors.lastname: Harju
authors.forename: Dexter
authors.initials: D
authors.lastname: Canoy
authors.forename: Marjo-Riitta
authors.initials: MR
authors.lastname: Järvelin
mesh_terms: D000293:Adolescent; D001249:Asthma / Q000453:epidemiology* / Q000473:pathology; D015992:Body Mass Index; D001835:Body Weight; D015331:Cohort Studies; D005260:Female; D005387:Finland / Q000453:epidemiology; D005865:Gestational Age; D006801:Humans; D016015:Logistic Models; D009765:Obesity / Q000453:epidemiology*; D011247:Pregnancy; D037841:Pregnant People / Q000523:psychology*; D011296:Prenatal Diagnosis / Q000523:psychology / Q000706:statistics & numerical data; D015995:Prevalence; D011446:Prospective Studies; D012135:Respiratory Sounds / Q000175:diagnosis; D012720:Severity of Illness Index; D012907:Smoking / Q000453:epidemiology / Q000523:psychology; D012959:Socioeconomic Factors; D011795:Surveys and Questionnaires; D015430:Weight Gain / Q000502:physiology