title: Obesity and poor asthma control in patients with severe asthma.
abstract: BACKGROUND
  Asthma is a public health problem as it leads to hospitalization and eventual death, particularly in its severe forms. Many studies have demonstrated an association between obesity and asthma.
  
  
  OBJECTIVE
  The aim of this study was to investigate the relationship between obesity and asthma control in a group of patients at a reference center for severe asthma in Brazil.
  
  
  METHODS
  This cross-sectional study was conducted in the outpatient central reference clinic of the Program for Control of Asthma in the State of Bahia. It included 508 subjects with severe asthma of both genders and above 18 years of age. All the participants answered a sociodemographic and a clinical questionnaire to collect information on their asthma and comorbidities, such as rhinitis and gastro-esophageal reflux disease (GERD). Participants also completed the Asthma Control Questionnaire, performed a spirometry test, and had their weight, height, and waist and hip circumferences registered.
  
  
  RESULTS
  Logistic regression analysis demonstrated a positive association between body mass index (BMI) and uncontrolled asthma [odds ratio (OR) 1.5; 95% confidence interval (CI) 1.02-2.20]. Symptoms of chronic rhinitis and GERD were also significantly associated with uncontrolled asthma (OR 3.68, 95% CI 1.50-9.01; and OR 2.78, 95% CI 1.91-4.03, respectively). There was no correlation between waist-to-hip ratios and asthma control.
  
  
  CONCLUSIONS
  In our sample of patients with severe asthma, those who were obese were more likely to have uncontrolled asthma than patients with a normal BMI. Nevertheless, this is not conclusive evidence for a direct causal association between obesity and poor asthma control. Future studies are necessary to dissect the relationship between obesity and asthma outcomes.
authors.affiliation: Department of Medicine, Faculdade de Medicina da Bahia, Federal University of Bahia, Bahia and National Research Council (CNPq), Salvador, Bahia, Brazil.
authors.forename: Luísa L
authors.initials: LL
authors.lastname: Barros
authors.forename: Adelmir
authors.initials: A
authors.lastname: Souza-Machado
authors.forename: Luciana B
authors.initials: LB
authors.lastname: Corrêa
authors.forename: Jéssica S
authors.initials: JS
authors.lastname: Santos
authors.forename: Constança
authors.initials: C
authors.lastname: Cruz
authors.forename: Mylene
authors.initials: M
authors.lastname: Leite
authors.forename: Lourdes
authors.initials: L
authors.lastname: Castro
authors.forename: Ana Carla
authors.initials: AC
authors.lastname: Coelho
authors.forename: Paula
authors.initials: P
authors.lastname: Almeida
authors.forename: Alvaro A
authors.initials: AA
authors.lastname: Cruz
mesh_terms: D000328:Adult; D001249:Asthma / Q000150:complications* / Q000503:physiopathology; D015992:Body Mass Index; D001938:Brazil; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D015999:Multivariate Analysis; D009765:Obesity / Q000150:complications* / Q000503:physiopathology; D012129:Respiratory Function Tests; D012959:Socioeconomic Factors; D055815:Young Adult