Table 1 Prevalence of development of respiratory symptoms by smoking habits

From Jansen et al. (8)

OR (respiratory symptoms)

Ex smoker

1.21

1–14 cig/day

1.89*

15–24 cig/day

2.98*

>24 cig/day

3.57*

From Lindström et al. (10)

% (Dyspnea grade 3)-Norrbotten

% (Dyspnea grade 3) Lapland

Nonsmokers

4.5 (m) 7.7(f)*

8.1(m) 17.2(f)*

Ex-smokers

46.7 (m) 12.8(f)*

18.5 (m) 20.4(f)*

smokers

10.3 (m) 11.7(f)*

12.7 (m) 18.2(f)*