title: Trends in childhood and parental asthma prevalence in Merseyside, 1991-1998.
abstract: OBJECTIVE
  To determine changes in childhood and parental asthma prevalence in Merseyside between 1991 and 1998.
  
  
  METHODS
  Three standardized cross-sectional respiratory health surveys using a parent-completed questionnaire were completed in 1991 (n = 1171), 1993 (n = 2368) and 1998 (n = 1964) amongst primary school children (5-11 years) attending the same 10 schools. The main outcome measures were prevalence of reported doctor diagnosed asthma, the symptom triad of cough, wheeze and breathlessness (C+W+B+) and parental asthma.
  
  
  RESULTS
  Significant changes in prevalence for all respiratory variables occurred between 1991 and 1998, except for the symptom triad C+W+B+. Between 1991 and 1998 the prevalence of reported doctor diagnosed asthma increased from 17.7 to 29.8 per cent (p < 0.001), history of wheezing increased from 22.5 to 29.4 per cent (p < 0.001). The symptom triad of C+W+B+ changed from 9.6 to 9.9 per cent (p = 0.78). Childhood reported hospital admissions for respiratory illness increased from 5.5 to 10.7 per cent (p < 0.001). Paternal asthma increased from 6.5 per cent in 1991, to 8.6 per cent in 1998 (p = 0.031), and maternal asthma almost doubled in the same period from 6.6 to 11.2 per cent (p < 0.001). Children living in poorer areas (Townsend score 8-11) were more likely to have doctor diagnosed asthma (OR = 2.99, 95 per cent CI, 2.06 to 4.33) and C+W+B+ (OR = 2.17, CI 1.13 to 4.18). Childhood obesity was significantly associated with increased risk of both doctor diagnosed asthma (OR = 1.74, 95 per cent CI, 1.29 to 2.37) and C+W+B+ (OR = 1.88, 95 per cent CI, 1.21 to 2.90).
  
  
  CONCLUSIONS
  A rising prevalence of reported doctor diagnosed asthma, but not C+W+B+ was observed during the 1990s in a low socio-economic area of Liverpool. Asthma prevalence was related to socio-economic deprivation and was associated with obesity. The rising prevalence of reported doctor diagnosed asthma is likely to be attributable to several factors, including changes in diagnostic labelling and the distribution of factors related to socio-economic status.
authors.affiliation: Child and Reproductive Health Group, Liverpool School of Medicine, Pembroke Place, Liverpool L35 EA, UK.
authors.forename: S
authors.initials: S
authors.lastname: Rizwan
authors.forename: J
authors.initials: J
authors.lastname: Reid
authors.forename: Y
authors.initials: Y
authors.lastname: Kelly
authors.forename: P E
authors.initials: PE
authors.lastname: Bundred
authors.forename: M
authors.initials: M
authors.lastname: Pearson
authors.forename: B J
authors.initials: BJ
authors.lastname: Brabin
mesh_terms: D000328:Adult; D000397:Air Pollution / Q000009:adverse effects* / Q000706:statistics & numerical data; D001249:Asthma / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology; D002648:Child; D003430:Cross-Sectional Studies; D004739:England / Q000453:epidemiology; D005260:Female; D006305:Health Status Indicators; D006306:Health Surveys; D006801:Humans; D016015:Logistic Models; D008297:Male; D010290:Parents; D015995:Prevalence; D012307:Risk Factors; D017062:Small-Area Analysis; D012923:Social Class; D011795:Surveys and Questionnaires; D014504:Urban Health / Q000706:statistics & numerical data* / Q000639:trends