title: Characteristics and severity of asthma in children with and without atopic conditions: a cross-sectional study.
abstract: BACKGROUND
  Childhood allergic diseases have a major impact on a child's quality of life, as well as that of their parents. We studied the coexistence of reported allergies in children who use asthma medication. Additionally, we tested the hypothesis that asthma severity is greater among children with certain combinations of co-morbid allergic conditions.
  
  
  METHODS
  For this cross-sectional study, 703 children (ages 4 to 12 years) from the PACMAN cohort study were selected. All of the children were regular users of asthma medication. The study population was divided into nine subgroups according to parental-reported allergies of the child (hay fever, eczema, food allergy or combinations of these). In order to assess whether these subgroups differed clinically, the groups were compared for child characteristics (age, gender, family history of asthma), asthma exacerbations in the past year (oral corticosteroids (OCS) use; asthma-related emergency department (ED) visits), asthma control, fractional exhaled nitric oxide level (FeNO), and antihistaminic usage.
  
  
  RESULTS
  In our study, 79.0% of the parents reported that their child suffered from at least one atopic condition (hay fever, food allergy and eczema), and one quarter of the parents (25.6%) reported that their child suffered from all three atopic conditions. Having more than one atopic condition was associated with an increased risk of OCS use (OR = 3.3, 95% CI = 1.6 - 6.6), ED visits (OR = 2.3, 95% CI = 1.2 - 4.6) in the past year and inadequate short term asthma control (OR = 1.9, 95% CI = 1.3 - 2.8).
  
  
  CONCLUSIONS
  Children who use asthma medication often also have other allergic conditions. Parental reported allergies were associated with a higher risk of more severe asthma (more asthma complaints and more asthma exacerbations).
authors.affiliation: Division of Pharmacoepidemiology & Clinical Pharmacology, Utrecht Institute for Pharmaceutical Sciences (UIPS), Faculty of Science, Utrecht University, P.O. Box 80082, David de Wied Building, Universiteitsweg 99, Utrecht, 3508 TB, The Netherlands. a.arabkhazaeli@uu.nl.
authors.forename: Ali
authors.initials: A
authors.lastname: Arabkhazaeli
authors.affiliation: Division of Pharmacoepidemiology & Clinical Pharmacology, Utrecht Institute for Pharmaceutical Sciences (UIPS), Faculty of Science, Utrecht University, P.O. Box 80082, David de Wied Building, Universiteitsweg 99, Utrecht, 3508 TB, The Netherlands. s.vijverberg@uu.nl.
authors.forename: Susanne J H
authors.initials: SJ
authors.lastname: Vijverberg
authors.affiliation: Department of Pediatric Respiratory Medicine, Wilhelmina Children's Hospital, University Medical Centre Utrecht, Lundlaan 6, Utrecht, 3584 EA, The Netherlands. F.C.vanErp@umcutrecht.nl.
authors.forename: Francine C
authors.initials: FC
authors.lastname: van Erp
authors.affiliation: Division of Pharmacoepidemiology & Clinical Pharmacology, Utrecht Institute for Pharmaceutical Sciences (UIPS), Faculty of Science, Utrecht University, P.O. Box 80082, David de Wied Building, Universiteitsweg 99, Utrecht, 3508 TB, The Netherlands. j.a.m.raaijmakers@uu.nl.
authors.forename: Jan A M
authors.initials: JA
authors.lastname: Raaijmakers
authors.affiliation: Department of Pediatric Respiratory Medicine, Wilhelmina Children's Hospital, University Medical Centre Utrecht, Lundlaan 6, Utrecht, 3584 EA, The Netherlands. K.vanderEnt@umcutrecht.nl.
authors.forename: Cornelis K
authors.initials: CK
authors.lastname: van der Ent
authors.affiliation: Division of Pharmacoepidemiology & Clinical Pharmacology, Utrecht Institute for Pharmaceutical Sciences (UIPS), Faculty of Science, Utrecht University, P.O. Box 80082, David de Wied Building, Universiteitsweg 99, Utrecht, 3508 TB, The Netherlands. a.h.maitland@uu.nl.
authors.forename: Anke H
authors.initials: AH
authors.lastname: Maitland van der Zee
mesh_terms: D001249:Asthma / Q000150:complications / Q000175:diagnosis* / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D006967:Hypersensitivity / Q000150:complications* / Q000453:epidemiology; D008297:Male; D009426:Netherlands / Q000453:epidemiology; D015995:Prevalence; D011788:Quality of Life; D012720:Severity of Illness Index