Table 1– Characteristics of the sample
Biomass groupTobacco groupp-value
Patient characteristics
 Subjects n2122
 Age years69.0±6.369.3±5.50.90
 Tobacco smoke exposure pack-years032.6±14.4
 Biomass smoke exposure hour-years275.4±101.00
 Height cm148.0±6.0154.0±3.00.003#
 Weight kg61.5±12.161.9±10.80.92
 BMI kg·m−228.5±6.226.8±4.20.29
Lung function
  FEV1 % pred46.7±14.950.3±12.20.38
  FVC % pred70.1±16.379.3±12.80.05
  FEV1 % pred54.5±14.957.7±12.30.44
  FVC % pred80.6±18.689.0±11.80.08
Lung volumes
 RV % pred181±67176±560.80
 TLC % pred130±27125±210.48
 RV/TLC %0.66±0.080.62±0.090.12
  • Data are presented as mean±sd, unless otherwise stated. BMI: body mass index; FEV1: forced expiratory volume in 1 s; FVC: forced vital capacity; RV: residual volume; TLC: total lung capacity. #: nonparametric test.