title: Investigation of factors associated with difficult-to-control asthma.
abstract: OBJECTIVE
  To determine the prevalence of factors associated with difficult-to-control asthma.
  
  
  METHODS
  Patients with severe asthma were selected from the outpatient asthma clinic of the Ribeirão Preto School of Medicine Hospital das Clínicas. The patients were divided into two groups: controlled severe asthma and difficult-to-control severe asthma. After new attempts to optimize the severe asthma treatment, a questionnaire was applied, and additional tests for factors associated with difficult-to-control asthma, such as environmental and occupational exposure, smoking history, social factors, rhinitis/sinusitis, gastroesophageal reflux disease (GERD), obstructive sleep apnea, congestive heart failure (CHF), pulmonary embolism, cystic fibrosis, vocal cord dysfunction, alpha-1 antitrypsin deficiency, and Churg-Strauss syndrome, were performed.
  
  
  RESULTS
  77 patients with severe asthma were selected, of which 47 suffered from hard-to-control asthma, being 68.1% female, with mean age of 44.4 years (+/-14.4), and forced expiratory volume in one second of 54.7% (+/-18.3). The most factors most often associated with difficult-to-control asthma were noncompliance with treatment (68%), rhinitis/sinusitis (57%), GERD (49%), environmental exposure (34%), occupational exposure (17%), smoking history (10%), obstructive sleep apnea (2%), and CHF (2%). At least one of these factors was identified in every case.
  
  
  CONCLUSIONS
  Noncompliance with treatment was the factor most often associated with difficult-to-control asthma, underscoring the need to investigate comorbidities in the evaluation of patients with this form of the disease.
authors.affiliation: Department of Clinical Medicine, Faculdade de Medicina de Ribeiro Preto da Universidade de São Paulo - FMRP/USP, Universityof São Paulo at Ribeirão Preto School of Medicine - Ribeirão Preto (SP) Brazil.
authors.forename: Ana Carla Sousa de
authors.initials: AC
authors.lastname: Araujo
authors.forename: Erica
authors.initials: E
authors.lastname: Ferraz
authors.forename: Marcos de Carvalho
authors.initials: Mde C
authors.lastname: Borges
authors.forename: João Terra
authors.initials: JT
authors.lastname: Filho
authors.forename: Elcio Oliveira
authors.initials: EO
authors.lastname: Vianna
mesh_terms: D000328:Adult; D000465:Algorithms; D001249:Asthma / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology* / Q000209:etiology*; D001938:Brazil / Q000453:epidemiology; D004781:Environmental Exposure / Q000009:adverse effects / Q000706:statistics & numerical data; D004812:Epidemiologic Methods; D005260:Female; D005764:Gastroesophageal Reflux / Q000175:diagnosis; D005938:Glucocorticoids / Q000627:therapeutic use; D006333:Heart Failure / Q000150:complications; D006801:Humans; D008297:Male; D016273:Occupational Exposure / Q000009:adverse effects / Q000706:statistics & numerical data; D012307:Risk Factors; D012852:Sinusitis / Q000150:complications; D012882:Skin Tests; D020181:Sleep Apnea, Obstructive / Q000150:complications; D012907:Smoking / Q000009:adverse effects; D017211:Treatment Failure; D016312:Treatment Refusal / Q000706:statistics & numerical data
chemical_list: D005938:Glucocorticoids