title: Is Gly16Arg β2 Receptor Polymorphism Related to Impulse Oscillometry in a Real-Life Asthma Clinic Setting?
abstract: OBJECTIVE
  We evaluated whether Gly16Arg beta2-receptor genotype relates to impulse oscillometry (IOS) in a real-life clinic setting.
  
  
  METHODS
  Patients with persistent asthma taking inhaled corticosteroid ± long-acting beta-agonist (ICS ± LABA) were evaluated. We compared genotype groups comprising either no Arg copies (i.e. GlyGly) versus one or two Arg copies (i.e. ArgArg or ArgGly). IOS outcomes included total airway resistance at 5 Hz (R5), central airway resistance at 20 Hz (R20), peripheral airway resistance (R5-R20), reactance at 5 Hz, area under reactance curve (AX) and resonant frequency (RF). In addition, we recorded ACQ-5 and salbutamol use.
  
  
  RESULTS
  One hundred and twelve ICS-treated asthmatic patients (mean ICS dose 1238 µg/day), mean age 43 years, ACQ 2.34, FEV1 82 %, R5 177 % were identified-89 were also taking LABA. 61 patients were GlyGly, while 14 were ArgArg and 37 were ArgGly. There were no significant differences in IOS outcomes, ACQ or salbutamol use between the genotypes. The allelic risk (as odds ratio) for less well-controlled asthma (as ACQ > 1.5) was 1.1 (95 % CI 0.72-1.68) in relation to each Arg copy with a corresponding odds ratio for abnormal R5-R20 > 0.07kPA/l.s being 0.91 (95 % CI 0.57-1.44). 71 % of patients had an ACQ > 1.5 in the GlyGly group, versus 67 % in GlyArg/ArgArg group, with corresponding figures for abnormal R5-R20 > 0.07 kPa/l.s being 69 versus 73 %.
  
  
  CONCLUSIONS
  In a real-life clinic setting for patients with poorly controlled persistent asthma taking ICS ± LABA, we found no evidence of any relationship of Gly16Arg to IOS, ACQ or salbutamol use.
authors.affiliation: Scottish Centre for Respiratory Research, Ninewells Hospital and Medical School, University of Dundee, Dundee, DD1 9SY, UK.
authors.forename: Sunny
authors.initials: S
authors.lastname: Jabbal
authors.affiliation: Scottish Centre for Respiratory Research, Ninewells Hospital and Medical School, University of Dundee, Dundee, DD1 9SY, UK.
authors.forename: Arvind
authors.initials: A
authors.lastname: Manoharan
authors.affiliation: Scottish Centre for Respiratory Research, Ninewells Hospital and Medical School, University of Dundee, Dundee, DD1 9SY, UK.
authors.forename: Joseph
authors.initials: J
authors.lastname: Lipworth
authors.affiliation: Scottish Centre for Respiratory Research, Ninewells Hospital and Medical School, University of Dundee, Dundee, DD1 9SY, UK.
authors.forename: William
authors.initials: W
authors.lastname: Anderson
authors.affiliation: Scottish Centre for Respiratory Research, Ninewells Hospital and Medical School, University of Dundee, Dundee, DD1 9SY, UK.
authors.forename: Philip
authors.initials: P
authors.lastname: Short
authors.affiliation: Scottish Centre for Respiratory Research, Ninewells Hospital and Medical School, University of Dundee, Dundee, DD1 9SY, UK. b.j.lipworth@dundee.ac.uk.
authors.forename: Brian
authors.initials: B
authors.lastname: Lipworth
mesh_terms: D000280:Administration, Inhalation; D000305:Adrenal Cortex Hormones / Q000008:administration & dosage; D058666:Adrenergic beta-2 Receptor Agonists / Q000008:administration & dosage; D000328:Adult; D000403:Airway Resistance; D000420:Albuterol / Q000008:administration & dosage; D001249:Asthma / Q000175:diagnosis / Q000188:drug therapy / Q000235:genetics* / Q000503:physiopathology; D016084:Bronchoconstriction; D001993:Bronchodilator Agents / Q000008:administration & dosage; D003430:Cross-Sectional Studies; D005260:Female; D005787:Gene Frequency; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D006801:Humans; D016015:Logistic Models; D008168:Lung / Q000187:drug effects / Q000503:physiopathology*; D008297:Male; D016017:Odds Ratio; D009991:Oscillometry / Q000379:methods*; D010641:Phenotype; D010865:Pilot Projects; D011110:Polymorphism, Genetic; D011237:Predictive Value of Tests; D018343:Receptors, Adrenergic, beta-2 / Q000187:drug effects / Q000235:genetics*; D012189:Retrospective Studies; D012307:Risk Factors
chemical_list: C553443:ADRB2 protein, human; D000305:Adrenal Cortex Hormones; D058666:Adrenergic beta-2 Receptor Agonists; D001993:Bronchodilator Agents; D018343:Receptors, Adrenergic, beta-2; D000420:Albuterol
keywords: Asthma; Beta-2 receptor; Genotype; Impulse oscillometry