Table 5—

Effect of exposure to chemicals and various types of fuel on selected respiratory symptoms: multiple logistic regression analysis adjusted for age, sex, smoking and county of residence

WheezeChest tightnessNocturnal coughAsthma attackChronic coughChronic phlegm
Sex
 Female1.8 (1.4–2.3)***1.4 (1.1–1.8)*1.6 (1.3–2.1)***1.9 (1.5–2.5)***1.3 (0.9–1.7)1.1 (0.8–1.4)
Age yrs
 30–493.1 (1.9–5.0)***2.4 (1.5–3.9)***2.2 (1.5–3.3)***3.4 (1.9–5.9)***3.9 (2.1–7.3)***3.7 (2.0–7.0)***
 >509.8 (6.1–15.7)***5.1 (3.1–8.2)***4.9 (3.3–7.3)***11.0 (6.4–19.2)***8.9 (4.7–16.6)***8.1 (4.3–15.2)***
Smoking
cigarettes·day−1
 Exsmoker12.0 (8.0–17.8)***8.7 (5.4–13.9)***10.4 (6.9–15.7)***14.2 (9.4–21.4)***13.0 (8.2–20.5)***12.5 (7.9–19.8)***
 <101.5 (0.96–2.3)0.67 (0.36–1.2)1.3 (0.85–2.0)1.6 (0.98–2.5)2.0 (1.3–3.2)**1.6 (1.0–2.7)
 10–191.4 (0.90–2.1)0.95 (0.58–1.6)1.4 (0.93–2.1)1.1 (0.69–1.8)1.7 (1.1–2.7)*1.7 (1.0–2.6)*
 20–292.3 (1.6–3.4)***1.7 (1.0–2.6)*2.4 (1.6–3.4)***2.1 (1.3–3.2)***3.2 (2.1–4.9)***2.8 (1.8–4.3)***
 >303.1 (2.2–4.2)***1.6 (1.0–2.5)*3.1 (2.2–4.4)***2.8 (1.9–4.0)***5.6 (3.9–8.0)***5.0 (3.5–7.2)***
Exposure
 Insecticide1.8 (1.2–2.6)**1.2 (0.8–1.9)1.9 (1.3–2.7)***1.9 (1.3–2.9)**2.2 (1.4–3.3)***2.0 (1.3–3.0)**
 Fertiliser1.4 (1.1–1.8)*2.2 (1.6–2.9)***1.5 (1.2–2.0)***1.3 (0.9–1.3 (0.9–1.7)1.4 (1.1–1.9)*
Fuel
 Coal0.98 (0.7–1.4)1.0 (0.6–1.5)0.89 (0.6–1.2)1.1 (0.7–1.6)0.98 (0.6–1.5)1.2 (0.7–1.9)
 Wood1.3 (0.9–1.9)1.9 (1.2–3.0)**1.0 (0.7–1.5)1.3 (0.9–2.1)1.4 (0.9–2.3)1.7 (1.1–2.9)*
 Cornstalk0.85 (0.6–1.2)1.1 (0.7–1.8)0.91 (0.6–1.3)1.0 (0.7–1.6)1.2 (0.8–1.9)1.5 (0.9–2.5)
County
 Tongxian1.6 (1.3–2.0)***2.0 (1.4–2.7)***2.1 (1.6–2.8)***1.4 (1.1–1.8)**1.4 (1.0–1.8)*1.3 (1.0–1.8)*
  • Data are presented as odds ratio (95% confidence interval)

  • Model: sex versus male

  • age versus <30 yrs

  • smoking versus nonsmoker

  • exposure: insecticide versus no insecticide and fertiliser versus no fertiliser

  • fuel: versus gas plus electricity plus oil

  • county versus Shunyi

  • Coal: gas plus coal

  • wood: gas plus coal plus wood

  • cornstalk: any fuel plus cornstalk or manure

  • *: p<0.05

  • **: p<0.01

  • ***: p<0.001