title: Individual-level socioeconomic status is associated with worse asthma morbidity in patients with asthma.
abstract: BACKGROUND
  Low socioeconomic status (SES) has been linked to higher morbidity in patients with chronic diseases, but may be particularly relevant to asthma, as asthmatics of lower SES may have higher exposures to indoor (e.g., cockroaches, tobacco smoke) and outdoor (e.g., urban pollution) allergens, thus increasing risk for exacerbations.
  
  
  METHODS
  This study assessed associations between adult SES (measured according to educational level) and asthma morbidity, including asthma control; asthma-related emergency health service use; asthma self-efficacy, and asthma-related quality of life, in a Canadian cohort of 781 adult asthmatics. All patients underwent a sociodemographic and medical history interview and pulmonary function testing on the day of their asthma clinic visit, and completed a battery of questionnaires (Asthma Control Questionnaire, Asthma Quality of Life Questionnaire, and Asthma Self-Efficacy Scale). General Linear Models assessed associations between SES and each morbidity measure.
  
  
  RESULTS
  Lower SES was associated with worse asthma control (F = 11.63, p < .001), greater emergency health service use (F = 5.09, p = .024), and worse asthma self-efficacy (F = 12.04, p < .01), independent of covariates. Logistic regression analyses revealed that patients with <12 years of education were 55% more likely to report an asthma-related emergency health service visit in the last year (OR = 1.55, 95%CI = 1.05-2.27). Lower SES was not related to worse asthma-related quality of life.
  
  
  CONCLUSIONS
  Results suggest that lower SES (measured according to education level), is associated with several indices of worse asthma morbidity, particularly worse asthma control, in adult asthmatics independent of disease severity. Results are consistent with previous studies linking lower SES to worse asthma in children, and add asthma to the list of chronic diseases affected by individual-level SES.
authors.affiliation: Montreal Behavioural Medicine Centre, Division of Chest Medicine, Research Center, Hôpital du Sacré-Coeur de Montréal--University of Montréal affiliated hospital, 5400 Gouin West, Montréal, Québec, Canada. simon.bacon@concordia.ca
authors.forename: Simon L
authors.initials: SL
authors.lastname: Bacon
authors.forename: Anne
authors.initials: A
authors.lastname: Bouchard
authors.forename: Eric B
authors.initials: EB
authors.lastname: Loucks
authors.forename: Kim L
authors.initials: KL
authors.lastname: Lavoie
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D001249:Asthma / Q000453:epidemiology*; D004632:Emergency Medical Services / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011788:Quality of Life; D011792:Quebec / Q000453:epidemiology; D018570:Risk Assessment / Q000379:methods; D012307:Risk Factors; D017678:Sex Distribution; D012959:Socioeconomic Factors; D055815:Young Adult