Table 1—

Characteristics of controls and asthmatic patients

ControlsAsthmatic patients
UnstableStable
Subjects n253030
M:F n5:2010:206:24
Atopy:nonatopy n0:2517:1312:18
Age yrs65.2±11.262.5±8.359.4±7.4
Age at onset yrsND49.9±9.949.7±10.5
Disease duration yrsND12.7±8.39.6±6.9
Serum IgE U·mL−1ND226 (10–3056)132 (15–2427)
FVC % pred104.8±20.389.2±15.8*,###108.3±14.0
FEV1 % pred107.6±17.363.3±10.3***,###106.2±16.3
FEV1/FVC %77.7±6.854.9±9.9***,###78.7±5.6
FEF25–75 % pred88.9±14.326.9±8.8***,###75.1±19.2*
FRC % pred90.4±11.8113.0±19.8*,#99.6±18.7
TLC % pred106.8±9.8111.5±12.0109.0±12.0
RV % pred91.5±9.8176.7±51.4***,###106.1±17.4
RV/TLC %32.4±6.847.9±8.2***,###36.2±5.2
DL,CO/VA % pred114.5±10.9115.6±22.3112.5±14.0
Pa,O2 kPa11.2±0.410.5±0.7***,##11±0.4
Pa,CO2 kPa5.2±0.14.9±0.35.2±0.3
  • Data are presented as absolute numbers, mean±sd or geometric mean (range)

  • M: male

  • F: female

  • Ig: immunoglobulin

  • FVC: forced vital capacity

  • FEV1: forced expiratory volume in one second

  • FEF25–75: forced mid-expiratory flow

  • FRC: functional residual capacity

  • TLC: total lung capacity

  • RV: residual volume

  • DL,CO: diffusing capacity of the lung for carbon monoxide

  • VA: alveolar volume

  • Pa,O2: arterial oxygen tension

  • Pa,CO2: arterial carbon dioxide tension

  • % pred: % predicted

  • ND: not determined

  • *: p<0.05

  • ***: p<0.001 versus control

  • # : p<0.05

  • ##: p<0.01

  • ###: p<0.001 versus stable asthma