Table 1.

Selected characteristics of the study population (N = 602,242) at enrollment with and without colon cancer and by tumor location and by gender

Participants with colon cancerParticipants without colon cancerPaAge-adjusted HR (95% CI)Proximal colon cancerbDistal colon cancerPc
Men (N = 299,376)2,152297,2241,048866
Age at enrollment (mean year)4944<0.000150490.0635
Age at diagnosis (mean year)646463<0.05
Follow-up years (median)d14130.095414140.4286
Years of education (%)
 <103423Ref3433
 10–1247540.99 (0.91–1.10)4648
 ≥131923<0.00011.01 (0.91–1.16)20190.6870
Level of physical activitye (%)
 Sedentary1918Ref1819
 Moderate50410.96 (0.86–1.08)5149
 Heavy3141<0.00010.92 (0.81–1.04)31320.718
BMI (kg/m2, mean)2625<0.051.05 (1.03–1.07)26260.0548
Smoking status at enrollment(%)
 Never smokers25332525
 Ever smokers7567<0.000174750.785
Women (n = 302,866)1,846301,020986654
Age at enrollment (mean year)5044<0.00015150<0.05
Age at diagnosis (mean year)626359<0.0001
Follow-up years (median)d1112<0.00011211<0.05
Years of education (%)
 <104025Ref4437
 10–1247550.99 (0.90–1.10)4548
 ≥131320<0.00010.90 (0.77–1.04)1115<0.05
Level of physical activitye(%)
 Sedentary2218Ref2024
 Moderate57540.98 (0.87–1.10)5954
 Heavy2128<0.00011.05 (0.91–1.21)20220.067
BMI (kg/m2, mean)2524<0.00011.01 (1.00–1.02)25250.2941
Smoking status at enrollment(%)
 Never45414445
 Ever5559<0.000156550,834
  • at test or χ2 test for difference between participants with and without primary colon cancer.

  • bThe numbers of proximal and distal cancer do not sum up to 3,998 as 444 colon cancer cases are categorized as unspecified.

  • ct test or χ2 test for difference between proximal and distal colon cancer cases.

  • dP of Wilcoxon/Mann–Whitney 2-sample test.

  • eLevel of physical activity; sedentary (reading, watching television, and sedentary activity), moderate (walking, bicycling, or similar activities ≥4 hours/wk), and heavy (light sports or heavy gardening ≥4 hours/wk, heavy exercise or daily competitive sports).