Table 2.
Associations of smoking with prevalent AFO and self-reported chronic bronchitis/emphysema among men
| Smoking habit (%) | AFO
|
Bronchitis/emphysema
|
|||
|---|---|---|---|---|---|
| %‡ | OR (95% CI)† | %‡ | OR (95% CI)† | ||
| Smoking category | |||||
| Never | 14.4 | 5.4 | 1.00 (0.95–1.06) | 3.3 | 1.00 (0.94–1.07) |
| Occasional | 11.2 | 5.2 | 0.93 (0.88–1.00) | 3.1 | 0.98 (0.90–1.06) |
| Exregular | 13.3 | 7.4 | 1.50 (1.44–1.57) | 5.6 | 1.85 (1.77–1.95) |
| Current regular | 61.1 | 7.1 | 1.37 (1.34–1.41) | 2.5 | 0.77 (0.74–0.80) |
| P heterogeneity | <0.0001 | <0.0001 | |||
| All regular | 74.4 | 7.2 | 1.42 (1.34–1.50) | 3.1 | 1.04 (0.96–1.11) |
| Amount smoked (g tobacco/day) in regular smokers | |||||
| Mean (SD), 18.3 (10.8) | |||||
| <5 | 6.1 | 6.6 | 1.34 (1.24–1.44) | 3.3 | 0.99 (0.87–1.11) |
| 5–14 | 28.9 | 6.9 | 1.36 (1.31–1.41) | 2.9 | 0.95 (0.90–1.01) |
| 15–24 | 46.2 | 7.4 | 1.46 (1.42–1.51) | 3.2 | 1.03 (0.99–1.08) |
| 25–34 | 10.4 | 7.6 | 1.47 (1.39–1.56) | 3.4 | 1.11 (1.02–1.21) |
| ≥35 | 8.4 | 7.4 | 1.42 (1.32–1.52) | 4.3 | 1.32 (1.21–1.45) |
| P trend | 0.014 | <0.0001 | |||
| Age started to smoke regularly (years) in regular smokers | |||||
| Mean (SD), 22.5 (7.0) | |||||
| ≥28 | 6.3 | 5.9 | 1.15 (1.10–1.21) | 4.2 | 0.76 (0.70–0.81) |
| 24–27 | 27.7 | 6.5 | 1.27 (1.21–1.34) | 3.7 | 0.92 (0.85–0.99) |
| 20–23 | 32.9 | 7.4 | 1.48 (1.43–1.54) | 3.4 | 1.12 (1.07–1.18) |
| 16–19 | 16.1 | 8.1 | 1.60 (1.54–1.67) | 2.8 | 1.24 (1.17–1.31) |
| <16 | 16.9 | 9.6 | 1.79 (1.68–1.92) | 2.4 | 1.35 (1.22–1.49) |
| P trend | <0.0001 | <0.0001 | |||
| Depth of inhalation in regular smokers | |||||
| Mouth/throat | 51.8 | 7.0 | 1.35 (1.31–1.39) | 2.9 | 0.94 (0.90–0.98) |
| Lung now | 12.3 | 6.4 | 1.27 (1.19–1.35) | 3.2 | 1.06 (0.97–1.15) |
| Lung always | 35.9 | 7.7 | 1.58 (1.52–1.64) | 3.6 | 1.19 (1.13–1.25) |
| P trend | <0.0001 | <0.0001 | |||
| Recent changes in amount smoked in current regular smokers§ | |||||
| No change | 66.5 | 6.8 | 1.28 (1.24–1.32) | 2.1 | 0.62 (0.59–0.65) |
| Increased a lot | 15.3 | 6.9 | 1.33 (1.25–1.42) | 2.4 | 0.72 (0.64–0.80) |
| Decreased a lot | 12.7 | 9.0 | 1.77 (1.68–1.87) | 4.3 | 1.20 (1.10–1.30) |
| P heterogeneity | <0.0001 | <0.0001 | |||
| Reason for stopping smoking in exregular smokers | |||||
| Ill health | 49.6 | 8.8 | 1.86 (1.77–1.96) | 8.4 | 2.79 (2.64–2.95) |
| Other reason | 50.4 | 5.6 | 1.08 (1.01–1.16) | 2.7 | 0.90 (0.81–0.99) |
| P heterogeneity | <0.0001 | <0.0001 | |||
Notes:
†
Adjusted for region, 5-year age group, age group × region interaction, education, and income, with the never-smoker category as the reference group. With the exception of the comparison of all regular versus never-smokers, the CIs are floated, so that comparisons can be made between any pair of categories.
‡
Prevalences of disease are directly standardized to the age and area structure of the study’s male population.
§
The variable was missing in 5.4% of male current smokers (N=6,963 men).
Abbreviations: AFO, airflow obstruction; OR, odds ratio; CI, confidence interval; SD, standard deviation; N, total number.