Table 2.

ORs (and 95% CIs) for smoking-related variables with EPL

Case/controlCrude OR (95% CI)PAdjusted OR (95% CI)aPAge-adjusted OR (95% CI)bP
Number of cigarettes per day
 Nonsmoker446/7,8411.00 (reference)1.00 (reference)1.00 (reference)
 <1173/1,2421.03 (0.80–1.33)0.8010.86 (0.66–1.12)0.2580.88 (0.68–1.14)0.335
 11-110/1,4181.36 (1.10–1.69)0.0051.04 (0.82–1.31)0.7761.12 (0.90–1.39)0.331
 21-15/1961.35 (0.79–2.29)0.2760.99 (0.57–1.71)0.9711.11 (0.65–1.90)0.714
 31-23/1542.63 (1.68–4.11)<0.0011.75 (1.09–2.80)0.0212.05 (1.30–3.23)0.002
Ptrend<0.0010.1170.029
Duration of smoking (years)
 Nonsmoker446/7,8411.00 (reference)1.00 (reference)1.00 (reference)
 <2045/9970.79 (0.58–1.09)0.1480.75 (0.54–1.04)0.0800.77 (0.56–1.06)0.109
 20-90/1,2601.26 (0.99–1.59)0.0571.05 (0.82–1.35)0.7071.12 (0.88–1.42)0.354
 35-75/6791.94 (1.50–2.51)<0.0011.15 (0.87–1.53)0.3171.27 (0.98–1.66)0.071
 50-11/742.61 (1.38–4.96)0.0031.29 (0.67–2.49)0.4411.43 (0.75–2.72)0.279
Ptrend<0.0010.2520.042
Age at starting smoking (years)
 Nonsmoker446/7,8411.00 (reference)1.00 (reference)1.00 (reference)
 25-149/2,1971.19 (0.96–1.44)0.0720.93 (0.75–1.14)0.4600.97 (0.80–1.18)0.742
 20-33/4861.19 (0.83–1.72)0.3420.89 (0.61–1.31)0.5531.00 (0.69–1.44)0.984
 <2039/3272.10 (1.48–2.96)<0.0011.71 (1.19–2.48)0.0041.96 (1.38–2.79)<0.001
Ptrend0.0300.0130.011
Cumulative amount of smoking (pack-years)
 Nonsmoker446/7,8411.00 (reference)1.00 (reference)1.00 (reference)
 <2081/1,5560.92 (0.72–1.17)0.4750.80 (0.62–1.03)0.0800.82 (0.64–1.05)0.115
 20-36/4971.27 (0.90–1.81)0.1781.09 (0.76–1.57)0.6521.14 (0.80–1.63)0.473
 30-36/4401.44 (1.01–2.05)0.0431.06 (0.74–1.53)0.7521.14 (0.80–1.63)0.463
 40-68/5172.31 (1.77–3.03)<0.0011.40 (1.03–1.89)0.0301.56 (1.18–2.06)0.002
Ptrend<0.0010.0430.002
Family smoking (exposure to secondhand smoking)
 No326/6,0621.00 (reference)1.00 (reference)1.00 (reference)
 Yes341/4,7891.32 (1.13–1.55)<0.0011.47 (1.25–1.74)<0.0011.37 (1.17–1.60)<0.001
  • aAdjusted for gender, age, BMI, education level, annual income and alcohol units consumed per day.

  • bAdjusted for age only.