Table 3 Impact of ever WS exposure on lung function decline independent of current smoking, airway obstruction, and CMH status at baseline^a

Basic model

 WS exposure × years

− 4.3 (1.9)

− 0.094 (0.038)

 P value

0.024

0.015

Basic model + current smoker × years

 WS exposure × years

− 4.1 (1.9)

− 0.088 (0.038)

 P value

0.033

0.021

 Current smoker × years

− 4.4 (1.7)

− 0.101 (0.033)

 P value

0.0082

0.0026

Basic model + airway obstruction × years

 WS exposure × years

− 4.3 (1.9)

− 0.094 (0.039)

 P value

0.025

0.016

 Airway obstruction × years

− 2.9 (1.9)

− 0.113 (0.039)

 P value

0.14

0.0041

Basic model + CMH × years

 WS exposure × years

− 4.0 (1.9)

− 0.088 (0.038)

 P value

0.038

0.022

 CMH × years

− 5.4 (2.0)

− 0.097 (0.040)

 P value

0.0061

0.014

Basic model + current smoker × years + airway obstruction × years + CMH × years

 WS exposure × years

− 3.7 (1.9)

− 0.080 (0.037)

 P value

0.050

0.034

 Current smoker × years

− 3.9 (1.9)

− 0.102 (0.034)

 P value

0.023

0.0026

 Airway obstruction × years

− 7.2 (2.0)

− 0.279 (0.038)

 P value

0.0002

 < 0.0001

 CMH × years

− 3.1 (2.1)

− 0.024 (0.041)

 P value

0.13

0.56