Table 4

Pooled multivariate relative risksa (95% confidence intervals) of lung cancer for quartiles of dietary carotenoids by cell typeb

CarotenoidQuartile 1Quartile 2Quartile 3Quartile 4P
Test for trendTest for between study heterogeneity for quartile 4Test for common effects by cell type for quartile 4c
α-Carotene
 Adenocarcinomas1.000.96 (0.82–1.12)1.14 (0.93–1.38)0.99 (0.84–1.17)0.960.40
 Small cell carcinomasc1.000.91 (0.76–1.10)1.08 (0.86–1.35)1.07 (0.88–1.29)0.530.68
 Squamous cell carcinomas1.000.83 (0.70–0.98)0.97 (0.82–1.15)0.97 (0.80–1.16)0.860.400.73
β-Carotene
 Adenocarcinomas1.000.98 (0.78–1.25)1.03 (0.88–1.20)1.04 (0.85–1.27)0.840.19
 Small cell carcinomasc1.001.13 (0.85–1.51)1.03 (0.83–1.27)1.18 (0.97–1.43)0.210.85
 Squamous cell carcinomas1.000.88 (0.73–1.07)0.96 (0.81–1.14)1.06 (0.89–1.27)0.500.780.66
β-Cryptoxanthin
 Adenocarcinomas1.000.79 (0.68–0.92)0.86 (0.72–1.03)0.80 (0.68–0.93)0.010.77
 Small cell carcinomasc1.000.84 (0.69–1.02)0.74 (0.62–0.90)0.66 (0.51–0.87)0.020.19
 Squamous cell carcinomas1.000.71 (0.60–0.84)0.76 (0.64–0.90)0.67 (0.56–0.80)<0.0010.940.24
Lutein/zeaxanthin
 Adenocarcinomas1.000.97 (0.78–1.21)0.99 (0.82–1.19)0.86 (0.73–1.02)0.100.39
 Small cell carcinomasc1.000.96 (0.79–1.15)1.00 (0.77–1.31)1.02 (0.85–1.23)0.710.51
 Squamous cell carcinomas1.000.94 (0.77–1.15)0.92 (0.78–1.10)1.01 (0.85–1.19)0.960.890.41
Lycopene
 Adenocarcinomas1.000.86 (0.73–1.01)0.98 (0.83–1.14)0.93 (0.79–1.09)0.640.96
 Small cell carcinomasc1.000.78 (0.65–0.94)0.89 (0.74–1.07)0.95 (0.79–1.14)0.980.96
 Squamous cell carcinomas1.000.74 (0.62–0.87)0.80 (0.67–0.95)0.86 (0.72–1.02)0.110.950.64
  • a Adjusted for education (<high school graduate, high school graduate, and >high school graduate), body mass index (<23, 23 to <25, 25 to <30, and ≥30 kg/m2), alcohol consumption (0, >0 to <5, 5 to <15, 15 to <30, and ≥30 g/day), energy (continuous), smoking status (current, past and never smokers), smoking duration for current smokers (continuous), smoking duration for past smokers (continuous), and amount smoked for current smokers (continuous). Because the α-Tocopherol, β-Carotene Cancer Prevention Study only includes current smokers, in this study we adjusted for smoking as smoking duration (continuous) and amount smoked (continuous).

  • b Number of lung cancer cases were as follows: 956 adenocarcinomas, 538 small cell carcinomas, and 901 squamous cell carcinomas.

  • c The women in the New York State Cohort were excluded because of too few cases with small cell carcinoma.