Table 1– Baseline patient characteristics
CharacteristicAcute exacerbationNo acute exacerbationp-value#
Subjects n75361
Age years63.7±8.462.8±7.90.29
Females17 (23)74 (20)0.67
Smoking status
 Never26 (35)89 (25)
 Former32 (43)177 (49)0.20
 Current17 (22)95 (26)
FVC % predicted69.3±17.778.1±17.6<0.001
DLCO % predicted62.5±19.367.1±19.2+0.11
Prednisone56 (74.7)202 (56.0)0.003
GORD treatment§57 (76.0)ƒ192 (53.2)<0.001

  • Data are presented as mean±sd or n (%), unless otherwise stated. FVC: forced vital capacity; DLCO: diffusing capacity of the lung for carbon monoxide; GORD: gastro-oesophageal reflux disease. #: overall tests of heterogeneity; : n=58; +: n=338; §: proton pump inhibitor or histamine 2 receptor (H2)-antagonist; ƒ: 11 out of 57 on proton pump inhibitor, 46 out of 57 on H2-antagonist.