Table 2

Proximity of residence to a major road as predictor of bronchiolitis obliterans syndrome (BOS) and mortality

ModelProximity to a major road ≤171 vs >171 m*Each 10-fold increase in distance
HR95% CIp-ValueHR95% CIp-Value
Incidence of BOS
Unadjusted2.061.39 to 3.05<0.0010.620.47 to 0.850.004
Adjusted for multiple covariates2.151.44 to 3.22<0.0010.570.44 to 0.81<0.001
Adjusted for multiple covariates and PM10 background levels§2.181.44 to 3.01<0.0010.580.43 to 0.810.001
Incidence of mortality
Unadjusted2.201.25 to 3.860.0060.630.40 to 0.990.047
Adjusted for multiple covariates1.991.09 to 3.610.0240.720.45 to 0.960.034
Adjusted for multiple covariates and PM10 background levels§2.261.20 to 4.270.0120.580.36 to 0.930.024
  • * Patients were assigned to categories according to distance from home to major roads based on lowest tertile.

  • Continuous analysis based on log-distance; hazard ratio (HR) associated with a 10-fold increase in distance between home and a major road.

  • Adjusted for sex, age, type of transplantation (single or double lung transplantation), infection with cytomegalovirus (CMV) and non-CMV infections, acute rejections, socioeconomic status, and a time factor to adjust for possible time trends.

  • § Background levels of particulate matter with a diameter less than 10 μm (PM10) at home based on interpolated data (4 by 4 km grids).