Table 2.

RRs with 95% CIs for colorectal cancer by sex and quartile of energy-adjusted intake of total dietary fiber in the JACC Study, 1988 to 1997

Quartiles of energy-adjusted intake of total dietary fiber
Ptrend
1234
Men and women combined (n = 43,115)
Person-years78,84981,22083,14584,059
Colorectal cancer
    Number of cancer cases97114102130
    Age- and sex-adjusted RR (95% CI)1.001.03 (0.78-1.35)0.83 (0.63-1.10)0.90 (0.69-1.18)0.23
    Multivariate RR (95% CI)*1.000.96 (0.72-1.27)0.72 (0.53-0.99)0.73 (0.51-1.03)0.028
Colon cancer
    Number of cancer cases71796081
    Age- and sex-adjusted RR (95% CI)1.000.97 (0.70-1.33)0.66 (0.47-0.93)0.74 (0.53-1.03)0.019
    Multivariate RR (95% CI)*1.000.90 (0.64-1.26)0.56 (0.38-0.83)0.58 (0.38-0.88)0.002
Rectal cancer
    Number of cancer cases25304047
    Age- and sex-adjusted RR (95% CI)1.001.06 (0.62-1.80)1.30 (0.78-2.14)1.33 (0.81-2.18)0.19
    Multivariate RR (95% CI)*1.000.98 (0.56-1.70)1.13 (0.64-2.00)1.10 (0.59-2.07)0.67
Men (n = 16,636)
Person-years30,63131,85532,22432,187
Colorectal cancer
    Number of cancer cases51765477
    Age-adjusted RR (95% CI)1.001.27 (0.89-1.82)0.82 (0.56-1.21)1.00 (0.69-1.44)0.41
    Multivariate RR (95% CI)*1.001.12 (0.77-1.62)0.62 (0.40-0.96)0.69 (0.43-1.11)0.023
Colon cancer
    Number of cancer cases33482642
    Age-adjusted RR (95% CI)1.001.23 (0.79-1.91)0.60 (0.35-1.00)0.80 (0.50-1.28)0.068
    Multivariate RR (95% CI)*1.001.06 (0.66-1.69)0.43 (0.24-0.76)0.52 (0.28-0.96)0.004
Rectal cancer
    Number of cancer cases18232735
    Age-adjusted RR (95% CI)1.001.10 (0.59-2.05)1.19 (0.65-2.17)1.34 (0.74-2.40)0.31
    Multivariate RR (95% CI)*1.000.96 (0.50-1.83)0.91 (0.46-1.80)0.95 (0.45-2.02)0.89
Women (n = 26,479)
Person-years48,21949,36650,92151,872
Colorectal cancer
    Number of cancer cases46384853
    Age-adjusted RR (95% CI)1.000.75 (0.49-1.15)0.86 (0.57-1.29)0.80 (0.53-1.19)0.42
    Multivariate RR (95% CI)*1.000.73 (0.47-1.14)0.84 (0.54-1.33)0.75 (0.46-1.25)0.41
Colon cancer
    Number of cancer cases38313439
    Age-adjusted RR (95% CI)1.000.73 (0.46-1.18)0.73 (0.46-1.16)0.70 (0.44-1.10)0.15
    Multivariate RR (95% CI)*1.000.72 (0.44-1.18)0.71 (0.42-1.20)0.64 (0.36-1.13)0.15
Rectal cancer
    Number of cancer cases771312
    Age-adjusted RR (95% CI)1.000.92 (0.32-2.62)1.57 (0.62-3.95)1.27 (0.49-3.29)0.42
    Multivariate RR (95% CI)*1.001.15 (0.39-3.38)2.14 (0.78-5.83)1.82 (0.59-5.65)0.19
  • * The RRs were adjusted for age (as a continuous variable), sex, area (Hokkaido and Tohoku, Kanto, Chubu, Kinki, Chugoku, or Kyushu), educational level (attended school until the age of ≤15, 16-18, or ≥19 y), family history of colorectal cancer in parents and/or siblings (yes or no), alcohol consumption [never drink, ex-drinkers, or current drinkers who consume <2 or ≥2 Japanese drinks (<46 or ≥46 g of ethanol) per day for men, and never drink, ex-drinkers, or current drinkers for women], smoking (never smoke, ex-smokers, or current smokers), BMI (<20.0, 20.0-24.9, or ≥25.0 kg/m2), daily walking habits (≤30 or >30 min/day), exercise (seldom or never, or 1-2, 3-4, or ≥5 h a week), sedentary work (yes or no), consumption of beef (almost never, 1-2 times a month, 1-2 times a week, ≥3 times a week) and pork (almost never, 1-2 times a month, 1-2 times a week, ≥3 times a week), energy intake (as a continuous variable), and energy-adjusted intakes of folate, calcium, and vitamin D (sex-specific quartile for each).