Table 5

Lung cancer in twin pairs discordant for smoking at baseline by zygosity and smoking status

Smoking discordanceZygosityPairs in which smoker had lung cancer and the non-smoking co-twin did notPairs in which non-smoker had lung cancer and the smoking co-twin did notHRs (95% CI); p Value
Ever/neverMZ3555.4 (2.1 to 14.0); p=0.0005
DZ145285.0 (3.2 to 7.9); p=1.4e–12
Current/neverMZ3146.0 (2.1 to 17.3) p=0.001
DZ124205.9 (3.5 to 9.8) p=1.4e–11
  • DZ, dizygotic; MZ, monozygotic.