Table 5

Associations between indices of asthma and risk factors among woodworkers; OR (95% CI) in logistic regression analyses

Independent variablesOutcome variables
Asthma symptoms† (n = 247)*Work related asthma symptoms‡ (n = 136)*Asthma symptoms + BHR§ (n = 118)*Clinical asthma¶ (n = 181)*
*Numbers in the final model.
†Asthma symptoms according to the appendix. Reference: no respiratory symptoms.
‡Work related wheezing or work related self reported asthma. Reference: no work related asthma symptoms.
§BHR + symptoms. Baseline FEV1 is included in the model. Reference: no asthma symptoms, no BHR.
¶Persons with asthma symptoms and either (1) BHR or (2) BDIR or (3) increased PEF variability or (4) wheezing or chest tightness by exposure to pollen or animals. Reference: no respiratory symptoms, no objective criteria suggestive of asthma.
**All models include a “dummy” variable adjusting for the stratified sampling design.
Wood dust, 0.80–0.99 mg/m3,1.273.615.682.08
ref. <0.80(0.52–3.08)(0.83–15.72(0.62–51.64)(0.68–6.37)
Wood dust, 1.0–1.39 mg/m3,1.222.053.812.01
ref <0.80(0.53–2.82)(0.47–9.03)(0.49–33.20)(0.73–5.53)
Wood dust, >1.39 mg/m3,2.306.4318.303.29
ref <0.80(0.95–5.56)(1.57–26.43)(1.96–170.77)(1.09–9.96)
Smoking, 1/0, reference = no3.254.133.814.01
smoking(1.75–6.06)(1.55–11.02)(1.11–13.07)(1.87–8.62)
Atopy, 1/0, reference = no atopy5.017.2418.715.24
(2.60–9.67)(2.59–20.28)(4.78–73.25)(2.38–11.53)
Additional variables included in the final model**Gender, sideline occupation, previous dusty non-woodworking jobsGender, age, education level, sideline occupationGender, age, sideline occupation, beech, baseline FEV1Gender, sideline occupation, previous dusty non-woodworking jobs