Table 2

Smoking markers

Current smokers
(n=12)		Ex-smokers
(n=25)		Never smokers
(n=64)		P value
Pack years of smoking2.13 (0.59–3.48)2.13 (0.05–5.40)0.00 (0.00–0.00)0.467*
Breath CO (ppm)9 (3.5–21)2 (2–3)1 (1–2)<0.001
Urine cotinine (ng/mL)837 (22.42–1571.8)22.42 (22.42–22.42)22.42 (22.42–22.42)<0.001

  • Values presented as median (IQR).

  • *Comparison between current and ex-smokers only.

  • CO, carbon monoxide.