Table 5– Logistic regression model excluding ex-smokers, comparing smoking dose–response with dyspnoea
Independent variablesCrude OR (95% CI)p-valueFemales and malesMales only#
Adjusted OR (95% CI)p-valueAdjusted OR (95% CI)p-value
Females and males
 Nonsmokers1.001.00
 ≤10 cigarettes per day1.29 (1.08–1.55)0.0051.37 (1.07–1.76)0.013
 >10 cigarettes per day1.27 (1.03–1.56)0.0261.40 (1.04–1.87)0.027**
Males only
 Nonsmokers1.001.00
 ≤10 cigarettes per day1.75 (1.29–2.38)<0.0011.46 (1.05–2.03)0.021
 >10 cigarettes per day1.85 (1.34–2.54)<0.001**1.48 (1.06–2.08)0.022**
Age1.03 (1.02–1.04)<0.0011.03 (1.02–1.04)<0.001
Education0.96 (0.94–0.98)<0.0010.96 (0.93–0.99)0.014
Sex1.56 (1.24–1.97)<0.001
High well arsenic1.33 (1.14–1.54)<0.0011.22 (0.97–1.55)0.091
Systolic BP1.00 (0.99–1.00)0.6961.00 (0.99–1.00)0.309
BMI group+
 11.13 (0.96–1.32)0.1381.22 (0.95–1.57)0.116
 21.42 (1.07–1.88)0.0162.10 (1.30–3.39)0.002
  • BP: blood pressure; BMI: body mass index. #: females not analysed separately, since there were only 15 females who smoked >10 cigarettes per day; : high arsenic was ≥50 μg·L−1; +: BMI categorised as low (<18.5 kg·m−2; group 1) and high (≥25 kg·m−2; group 2). **: p<0.01 by Chi-squared test for trend.