Table 5

RRsa (95% CIs) for quintiles (Q) or tertiles (T) of dietary intake of carotenoids, vitamins C and E, and folate, among never-smokers, former smokers, and current smokers: Netherlands Cohort Study 1986–1992

Quintiles/tertilesNever-smokersbFormer smokersbCurrent smokersb
Cases: n = 35Cases: n = 312Cases: n = 487
Subcohort: n = 203Subcohort: n = 728Subcohort: n = 476
α-Carotene
Q/T 1c1.001.001.00
Q/T 21.32 (0.46–3.79)0.63 (0.38–1.03)0.58 (0.38–0.90)
Q/T 31.61 (0.61–4.21)0.53 (0.32–0.88)0.79 (0.52–1.21)
Q 40.74 (0.46–1.19)0.83 (0.54–1.28)
Q 50.96 (0.60–1.56)0.76 (0.49–1.17)
P-trend0.270.940.41
β-Carotene
Q/T 1c1.001.001.00
Q/T 22.35 (0.83–6.65)0.62 (0.39–1.00)0.82 (0.54–1.25)
Q/T 31.98 (0.75–5.26)0.72 (0.44–1.19)0.83 (0.54–1.27)
Q 40.77 (0.48–1.24)0.79 (0.51–1.24)
Q 50.83 (0.51–1.34)0.74 (0.47–1.16)
P-trend0.140.580.05
Lutein/Zeaxanthin
Q/T 1c1.001.001.00
Q/T 20.83 (0.29–2.35)0.83 (0.52–1.33)0.74 (0.49–1.13)
Q/T 31.35 (0.56–3.26)0.59 (0.36–0.96)0.84 (0.54–1.29)
Q 40.88 (0.54–1.44)0.64 (0.42–0.99)
Q 50.66 (0.39–1.09)0.69 (0.45–1.07)
P-trend0.420.050.003
β-Cryptoxantin
Q/T 1c1.001.001.00
Q/T 20.50 (0.18–1.41)0.89 (0.55–1.42)0.69 (0.45–1.05)
Q/T 30.86 (0.36–2.06)0.68 (0.41–1.13)0.61 (0.40–0.93)
Q 40.76 (0.47–1.24)0.58 (0.37–0.90)
Q 51.08 (0.67–1.73)0.51 (0.33–0.79)
P-trend0.760.98<0.0001
Lycopene
Q/T 1c1.001.001.00
Q/T 20.92 (0.32–2.65)0.92 (0.57–1.49)0.72 (0.47–1.09)
Q/T 31.54 (0.61–3.90)1.21 (0.75–1.96)0.89 (0.58–1.37)
Q 40.97 (0.59–1.60)1.08 (0.71–1.66)
Q 51.06 (0.64–1.74)0.81 (0.53–1.23)
P-trend0.260.680.74
Vitamin Cd
Category 1c1.001.001.00
Category 20.72 (0.26–1.99)0.75 (0.50–1.12)0.70 (0.49–1.01)
Category 30.67 (0.25–1.79)0.84 (0.56–1.27)0.54 (0.38–0.78)
P-trend0.390.38<0.0001
Vitamin E
Q/T 1c1.001.001.00
Q/T 20.80 (0.32–2.02)1.39 (0.85–2.29)1.19 (0.78–1.82)
Q/T 30.67 (0.26–1.67)1.06 (0.64–1.76)1.20 (0.78–1.85)
Q 40.98 (0.59–1.64)1.12 (0.72–1.72)
Q 51.19 (0.71–1.98)0.97 (0.62–1.53)
P-trend0.320.940.79
Folate
Q/T 1c1.001.001.00
Q/T 21.04 (0.39–2.77)0.72 (0.45–1.15)0.71 (0.47–1.07)
Q/T 31.09 (0.44–2.72)0.79 (0.50–1.26)0.75 (0.48–1.16)
Q 40.79 (0.49–1.29)0.37 (0.24–0.58)
Q 50.72 (0.45–1.17)0.63 (0.41–0.98)
P-trend0.820.16<0.0001
  • a Adjusted for highest educational level, family history of lung cancer, and age. For current smokers and former smokers, also adjusted for years of smoking cigarettes and number of cigarettes per day (continuous).

  • b RR (95% CI).

  • c Reference category.

  • d Category 1, quintile 1; Category 2, quintiles 2 and 3; Category 3, quintiles 4 and 5.