Table 4

Association between lung cancer and exposure to endotoxins by smoking status

Never/light smokers*Heavy smokers†
CasesControlsOR‡95% ClCasesControlsOR‡95% Clp-Value Interaction§
NNNN
Exposure to endotoxins
Never¶55920901.00Reference18737971.00Reference
Ever**925050.64(0.49 to 0.85)3731520.87(0.7 to 1.1)0.01
Duration of exposure (years)
≤6371291.13(0.75 to 1.7)142560.96(0.67 to 1.36)
6–14)241190.72(0.44 to 1.20)87301.15(0.73 to 1.80)
>14–34171160.53(0.30 to 0.96)69420.62(0.40 to 0.95)
>34131410.26(0.14 to 0.51)72240.81(0.48 to 1.33)
Missing130.01
Cumulative exposure (UE*years)
Quartile 1431091.66(1.1 to 2.5)126560.97(0.68 to 1.38)
Quartile 2191250.6(0.34 to 1.01)129421.03(0.7 to 1.52)
Quartile 3211280.57(0.34 to 0.95)66330.61(0.38 to 0.98)
Quartile 481430.14(0.06 to 0.32)49200.8(0.45 to 1.4)
Missing1310.0003
Time since cessation of exposure (years)
≤5101430.28(0.14 to 0.57)62290.88(0.54 to 1.43)
>5–21181270.42(0.23 to 0.75)82320.92(0.59 to 1.44)
>21–39271121.02(0.64 to 1.62)121550.9(0.62 to 1.29)
>39361230.93(0.6 to 1.43)106360.81(0.53 to 1.24)
Missing120.007
p value§=0.007
  • *Never/light smokers were subjects with Cumulative Smoking Index (CSI)≤1. 

  • †Heavy smokers were subjects with CSI>1 

  • ‡OR adjusted for age at interview, department, sex, number of job periods, education and occupational exposure to asbestos. The never exposed to endotoxins are always the reference group. 

  • §p Value for interaction between endotoxins and smoking status (using the likelihood ratio test). 

  • Never means having no job in work environment group potentially exposed to endotoxins. 

  •  **Ever means having held at least one job in work environment group potentially exposed to endotoxins.