Adjusted odds ratios for respiratory symptoms and physician consultations by daily amount of SHS exposure (cigarette-hours)¶ at work in males
| ⩽4 cigarette-hours OR† (95% CI) | >4 to 16 cigarette-hours OR† (95% CI) | >16 to 48 cigarette-hours OR† (95% CI) | >48 cigarette-hours OR† (95% CI) | p for linear trend | |||||
|---|---|---|---|---|---|---|---|---|---|
| *p<0.05; **p<0.01; ***p<0.001. | |||||||||
| †Within each smoking category, the reference group is current smokers without SHS exposure nearby at work; odds ratios are adjusted for age, marital status, educational attainment, police rank, type of police duties, exposure to self perceived dusty or polluted environment in previous job, and SHS exposure at home. Additional adjustment for amount of smoking and duration of smoking was made in current smokers, and for smoking status in the analysis of current smokers and never-smokers combined. | |||||||||
| ‡Western physicians and Chinese traditional doctors. | |||||||||
| §p for interaction for SHS exposure variables and smoking status. A significant p value indicates significant difference in odds ratios between current smokers and never-smokers. | |||||||||
| ¶Cigarette-hours were calculated by multiplying exposure to average number of cigarettes smoked by co-workers nearby in one hour with 8 hours per day. | |||||||||
| Throat problems | |||||||||
| Current smokers | 1.38** | (1.08 to 1.75) | 1.39** | (1.09 to 1.77) | 1.96*** | (1.55 to 2.49) | 1.79*** | (1.41 to 2.28) | <0.001 |
| Never-smokers | 1.53*** | (1.21 to 1.92) | 2.04*** | (1.62 to 2.57) | 2.62*** | (2.07 to 3.32) | 2.79*** | (2.21 to 3.53) | <0.001 |
| p for interaction§ | 0.675 | 0.099 | 0.245 | <0.05 | |||||
| Cough, morning | |||||||||
| Current smokers | 1.32 | (1.00 to 1.74) | 1.69*** | (1.29 to 2.22) | 2.02*** | (1.55 to 2.64) | 2.06*** | (1.57 to 2.69) | <0.001 |
| Never-smokers | 1.17 | (0.85 to 1.59) | 1.72*** | (1.27 to 2.33) | 2.12*** | (1.56 to 2.87) | 2.10*** | (1.55 to 2.85) | <0.001 |
| p for interaction | 0.608 | 0.806 | 0.878 | 0.793 | |||||
| Cough, day or night | |||||||||
| Current smokers | 1.24 | (0.93 to 1.66) | 1.70*** | (1.28 to 2.25) | 2.21*** | (1.68 to 2.91) | 2.14*** | (1.62 to 2.82) | <0.001 |
| Never-smokers | 1.21 | (0.88 to 1.67) | 1.84*** | (1.35 to 2.49) | 2.20*** | (1.61 to 2.99) | 2.24*** | (1.65 to 3.04) | <0.001 |
| p for interaction | 0.881 | 0.977 | 0.716 | 0.812 | |||||
| Cough, chronic | |||||||||
| Current smokers | 1.86* | (1.04 to 3.30) | 1.82* | (1.02 to 3.23) | 2.76*** | (1.60 to 4.75) | 3.69*** | (2.16 to 6.30) | <0.001 |
| Never-smokers | 1.45 | (0.74 to 2.83) | 2.76*** | (1.48 to 5.13) | 3.06*** | (1.63 to 5.74) | 3.58*** | (1.93 to 6.61) | <0.001 |
| p for interaction | 0.519 | 0.339 | 0.931 | 0.698 | |||||
| Phlegm, morning | |||||||||
| Current smokers | 1.00 | (0.79 to 1.28) | 1.19 | (0.94 to 1.52) | 1.52*** | (1.20 to 1.93) | 1.66*** | (1.31 to 2.11) | <0.001 |
| Never-smokers | 1.27 | (0.95 to 1.68) | 1.73*** | (1.31 to 2.28) | 2.23*** | (1.69 to 2.95) | 2.83*** | (2.16 to 3.71) | <0.001 |
| p for interaction | 0.216 | 0.086 | 0.092 | <0.05 | |||||
| Phlegm, day or night | |||||||||
| Current smokers | 1.10 | (0.83 to 1.46) | 1.80*** | (1.38 to 2.35) | 1.75*** | (1.34 to 2.28) | 1.94*** | (1.49 to 2.53) | <0.001 |
| Never-smokers | 1.42* | (1.02 to 1.98) | 1.83*** | (1.32 to 2.54) | 2.38*** | (1.71 to 3.30) | 2.77*** | (2.01 to 3.82) | <0.001 |
| p for interaction | 0.303 | 0.885 | 0.271 | 0.304 | |||||
| Phlegm, chronic | |||||||||
| Current smokers | 1.26 | (0.85 to 1.87) | 1.56* | (1.07 to 2.29) | 1.62* | (1.11 to 2.36) | 2.24*** | (1.56 to 3.22) | <0.001 |
| Never-smokers | 1.09 | (0.65 to 1.85) | 1.58 | (0.96 to 2.60) | 2.64*** | (1.63 to 4.26) | 3.38*** | (2.13 to 5.38) | <0.001 |
| p for interaction | 0.740 | 0.864 | 0.123 | 0.372 | |||||
| Any cough or phlegm | |||||||||
| Current smokers | 1.14 | (0.90 to 1.43) | 1.60*** | (1.27 to 2.01) | 1.76*** | (1.40 to 2.21) | 1.89*** | (1.50 to 2.38) | <0.001 |
| Never-smokers | 1.24 | (0.98 to 1.56) | 1.77*** | (1.40 to 2.23) | 2.35*** | (1.85 to 2.98) | 2.52*** | (1.99 to 3.18) | <0.001 |
| p for interaction | 0.625 | 0.885 | 0.184 | 0.314 | |||||
| Increased cough or phlegm | |||||||||
| Current smokers | 1.48* | (1.10 to 2.00) | 1.77*** | (1.31 to 2.38) | 1.99*** | (1.49 to 2.66) | 2.00*** | (1.50 to 2.68) | <0.001 |
| Never-smokers | 1.34 | (0.99 to 1.80) | 1.92*** | (1.44 to 2.57) | 2.35*** | (1.75 to 3.15) | 2.17*** | (1.62 to 2.92) | <0.001 |
| p for interaction | 0.441 | 0.896 | 0.752 | 0.574 | |||||
| Ever wheezing | |||||||||
| Current smokers | 1.16 | (0.80 to 1.69) | 1.28 | (0.89 to 1.86) | 1.41 | (0.98 to 2.02) | 1.66** | (1.16 to 2.37) | <0.01 |
| Never-smokers | 1.28 | (0.85 to 1.91) | 1.62* | (1.09 to 2.41) | 2.33*** | (1.58 to 3.43) | 1.98*** | (1.34 to 2.93) | <0.001 |
| p for interaction | 0.711 | 0.467 | 0.057 | 0.589 | |||||
| Blocked or running nose | |||||||||
| Current smokers | 1.31* | (1.04 to 1.66) | 1.07 | (0.84 to 1.35) | 1.43** | (1.13 to 1.80) | 1.32* | (1.04 to 1.67) | <0.05 |
| Never-smokers | 1.53*** | (1.23 to 1.91) | 1.81*** | (1.44 to 2.26) | 1.92*** | (1.53 to 2.42) | 2.30*** | (1.83 to 2.89) | <0.001 |
| p for interaction | 0.218 | <0.01 | 0.060 | <0.01 | |||||
| Any symptoms above | |||||||||
| Current smokers | 1.41** | (1.11 to 1.80) | 1.55*** | (1.21 to 1.98) | 1.92*** | (1.49 to 2.47) | 1.85*** | (1.43 to 2.38) | <0.001 |
| Never-smokers | 1.68*** | (1.37 to 2.06) | 2.25*** | (1.82 to 2.78) | 2.74*** | (2.19 to 3.42) | 3.16*** | (2.53 to 3.95) | <0.001 |
| p for interaction | 0.186 | 0.094 | 0.080 | <0.05 | |||||
| Physician consultations in past 14 days for respiratory symptoms‡ | |||||||||
| Current smokers | 1.51** | (1.10 to 2.07) | 1.36 | (0.98 to 1.88) | 1.53** | (1.12 to 2.10) | 1.51** | (1.10 to 2.07) | <0.05 |
| Never-smokers | 1.08 | (0.83 to 1.41) | 1.21 | (0.93 to 1.58) | 1.43** | (1.09 to 1.87) | 1.55*** | (1.19 to 2.01) | <0.001 |
| p for interaction | 0.061 | 0.540 | 0.290 | 0.803 | |||||