title: Association of asthma and hay fever with irregular menstruation.
abstract: BACKGROUND
  There is some evidence that asthmatic women are more likely to have abnormal sex hormone levels. A study was undertaken to determine whether asthma and allergy were associated with irregular menstruation in a general population, and the potential role of asthma medication for this association.
  
  
  METHODS
  A total of 8588 women (response rate 77%) participated in an 8 year follow up postal questionnaire study of participants of the ECRHS stage I in Denmark, Estonia, Iceland, Norway, and Sweden. Only non-pregnant women not taking exogenous sex hormones were included in the analyses (n = 6137).
  
  
  RESULTS
  Irregular menstruation was associated with asthma (OR 1.54 (95% CI 1.11 to 2.13)), asthma symptoms (OR 1.47 (95% CI 1.16 to 1.86)), hay fever (OR 1.29 (95% CI 1.05 to 1.57)), and asthma preceded by hay fever (OR 1.95 (95% CI 1.30 to 2.96)) among women aged 26-42 years. This was also observed in women not taking asthma medication (asthma symptoms: OR 1.44 (95% CI 1.09 to 1.91); hay fever: OR 1.27 (95% CI 1.03 to 1.58); wheeze preceded by hay fever: OR 1.76 (95% CI 1.18 to 2.64)). Irregular menstruation was associated with new onset asthma in younger women (OR 1.58 (95% CI 1.03 to 2.42)) but not in women aged 42-54 years (OR 0.62 (95% CI 0.32 to 1.18)). The results were consistent across centres.
  
  
  CONCLUSIONS
  Younger women with asthma and allergy were more likely to have irregular menstruation. This could not be attributed to current use of asthma medication. The association could possibly be explained by common underlying metabolic or developmental factors. The authors hypothesise that insulin resistance may play a role in asthma and allergy.
authors.affiliation: Institute of Medicine, University of Bergen, Norway. cecilie.svanes@med.uib.no
authors.forename: C
authors.initials: C
authors.lastname: Svanes
authors.forename: F Gomez
authors.initials: FG
authors.lastname: Real
authors.forename: T
authors.initials: T
authors.lastname: Gislason
authors.forename: C
authors.initials: C
authors.lastname: Jansson
authors.forename: R
authors.initials: R
authors.lastname: Jögi
authors.forename: E
authors.initials: E
authors.lastname: Norrman
authors.forename: L
authors.initials: L
authors.lastname: Nyström
authors.forename: K
authors.initials: K
authors.lastname: Torén
authors.forename: E
authors.initials: E
authors.lastname: Omenaas
mesh_terms: D000328:Adult; D001249:Asthma / Q000150:complications* / Q000453:epidemiology; D005060:Europe / Q000453:epidemiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008599:Menstruation Disturbances / Q000150:complications* / Q000453:epidemiology; D008875:Middle Aged; D016017:Odds Ratio; D015995:Prevalence; D012044:Regression Analysis; D006255:Rhinitis, Allergic, Seasonal / Q000150:complications* / Q000453:epidemiology; D011795:Surveys and Questionnaires