title: Measures of bronchodilator response of FEV1, FVC and SVC in a Swedish general population sample aged 50-64 years, the SCAPIS Pilot Study.
abstract: BACKGROUND
  Data are lacking from general population studies on how to define changes in lung function after bronchodilation. This study aimed to analyze different measures of bronchodilator response of forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC) and slow vital capacity (SVC).
  
  
  METHODS
  Data were derived from the Swedish Cardiopulmonary Bioimage Study (SCAPIS) Pilot study. This analysis comprised 1,050 participants aged 50-64 years from the general population. Participants were investigated using a questionnaire, and FEV1, FVC and SVC were recorded before and 15 minutes after inhalation of 400 µg of salbutamol. A bronchodilator response was defined as the relative change from baseline value expressed as the difference in units of percent predicted normal. Predictors of bronchodilator responses were assessed using multiple linear regression models. Airway obstruction was defined as FEV1/FVC ratio below lower limit of normal (LLN) before bronchodilation, and COPD was defined as an FEV1/FVC ratio below LLN after bronchodilation. Physician-diagnosed asthma was defined as an affirmative answer to "Have you ever had asthma diagnosed by a physician?". Asymptomatic never-smokers were defined as those not reporting physician-diagnosed asthma, physician-diagnosed COPD or emphysema, current wheeze or chronic bronchitis and being a lifelong never-smoker.
  
  
  RESULTS
  Among all subjects, the greatest bronchodilator responses (FEV1, FVC and SVC) were found in subjects with asthma or COPD. The upper 95th percentile of bronchodilator responses in asymptomatic never-smokers was 8.7% for FEV1, 4.2% for FVC and 5.0% for SVC. The bronchodilator responses were similar between men and women. In a multiple linear regression model comprising all asymptomatic never-smokers, the bronchodilator response of FEV1was significantly associated with airway obstruction and height.
  
  
  CONCLUSIONS
  When the bronchodilator response in asymptomatic never-smokers is reported as the difference in units of predicted normal, significant reversibility of FEV1, FVC and SVC to bronchodilators is ~9%, 4% and 5%, respectively.
authors.affiliation: Section of Occupational and Environmental Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg.
authors.forename: K
authors.initials: K
authors.lastname: Torén
authors.affiliation: Section of Occupational and Environmental Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg.
authors.forename: B
authors.initials: B
authors.lastname: Bake
authors.affiliation: Section of Occupational and Environmental Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg.
authors.forename: A-C
authors.initials: AC
authors.lastname: Olin
authors.affiliation: Department of Clinical Science, Lund University, Malmö.
authors.forename: G
authors.initials: G
authors.lastname: Engström
authors.affiliation: Division of Medicine/Respiratory Medicine, Department of Public Health and Clinical Medicine, Umeå University, Umeå.
authors.forename: A
authors.initials: A
authors.lastname: Blomberg
authors.affiliation: Department of Radiology, Institute of Clinical Sciences.
authors.forename: J
authors.initials: J
authors.lastname: Vikgren
authors.affiliation: Department of Internal Medicine/Lung Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg.
authors.forename: J
authors.initials: J
authors.lastname: Hedner
authors.affiliation: Department of Radiology, Institute of Clinical Sciences.
authors.forename: J
authors.initials: J
authors.lastname: Brandberg
authors.affiliation: Department of Respiratory Medicine; Department of Medicine and Health Sciences, Linköping University, Linköping.
authors.forename: H L
authors.initials: HL
authors.lastname: Persson
authors.affiliation: Respiratory Medicine Unit, Department of Medicine Solna, Centre for Molecular Medicine, Karolinska Institutet, Stockholm.
authors.forename: C M
authors.initials: CM
authors.lastname: Sköld
authors.affiliation: Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg.
authors.forename: A
authors.initials: A
authors.lastname: Rosengren
authors.affiliation: Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg.
authors.forename: G
authors.initials: G
authors.lastname: Bergström
authors.affiliation: Department of Medical Sciences, Clinical Physiology and Lung, Allergy and Sleep Research, Uppsala University, Uppsala, Sweden.
authors.forename: C
authors.initials: C
authors.lastname: Janson
mesh_terms: D000280:Administration, Inhalation; D058666:Adrenergic beta-2 Receptor Agonists / Q000008:administration & dosage*; D000420:Albuterol / Q000008:administration & dosage*; D001249:Asthma / Q000175:diagnosis / Q000453:epidemiology / Q000503:physiopathology*; D058070:Asymptomatic Diseases; D001993:Bronchodilator Agents / Q000008:administration & dosage*; D005260:Female; D005541:Forced Expiratory Volume / Q000187:drug effects*; D006801:Humans; D016014:Linear Models; D008168:Lung / Q000187:drug effects* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D029424:Pulmonary Disease, Chronic Obstructive / Q000175:diagnosis / Q000453:epidemiology / Q000503:physiopathology*; D012907:Smoking / Q000009:adverse effects; D011795:Surveys and Questionnaires; D013548:Sweden / Q000453:epidemiology; D013997:Time Factors; D014797:Vital Capacity / Q000187:drug effects*
chemical_list: D058666:Adrenergic beta-2 Receptor Agonists; D001993:Bronchodilator Agents; D000420:Albuterol
keywords: COPD; epidemiology; reversibility; spirometry