Table 5.

HRs and 95% CIs of colon cancer according to absolute weight change and BMI at baseline

Weight change (kg)Ptrend*
≤−2−1.9 to 1.92.0-4.95.0-9.9≥10.0
Men (Pinteraction = 0.16)
BMI <25
No. cases124444235
Person-years25,65767,39059,77343,11912,302
Age-adjusted HR (95% CI)0.75 (0.39-1.41)1 (reference)1.20 (0.79-1.82)0.92 (0.56-1.53)0.80 (0.32-2.02)0.46
Multivariable HR (95% CI)§0.73 (0.38-1.38)1 (reference)1.19 (0.78-1.80)0.91 (0.55-1.51)0.76 (0.30-1.93)0.40
BMI ≥25
No. cases3346342418
Person-years36,92050,82842,88231,81511,032
Age-adjusted HR (95% CI)1.03 (0.66-1.62)1 (reference)0.93 (0.60-1.45)0.96 (0.59-1.58)2.20 (1.27-3.81)0.04
    Multivariable HR (95% CI)§1.01 (0.65-1.58)1 (reference)0.93 (0.60-1.45)0.94 (0.57-1.55)2.09 (1.21-3.63)0.07
Women (Pinteraction = 0.72)
BMI <25
No. cases1547362912
Person-years28,59777,76173,59856,96218,374
Age-adjusted HR (95% CI)0.90 (0.50-1.61)1 (reference)0.85 (0.55-1.31)0.94 (0.59-1.50)1.32 (0.70-2.49)0.71
    Multivariable HR (95% CI)§0.87 (0.49-1.56)1 (reference)0.87 (0.56-1.34)0.98 (0.62-1.57)1.36 (0.72-2.58)0.56
BMI ≥25
No. cases4232192315
Person-years35,86331,26829,07128,14915,579
Age-adjusted HR (95% CI)1.18 (0.75-1.87)1 (reference)0.66 (0.37-1.16)0.88 (0.51-1.50)1.11 (0.60-2.05)0.71
Multivariable HR (95% CI)§1.15 (0.72-1.82)1 (reference)0.66 (0.38-1.17)0.89 (0.52-1.52)1.10 (0.60-2.04)0.71
  • *To test for linear trend, weight change was modeled as a continuous variable. The test was restricted to those who gained or maintained weight.

  • Value of BMI at baseline.

  • Age-adjusted HRs based on a stratified Cox model (year of birth: <1930, 1930-1934, 1935-1939, 1940-1944, ≥1945) using attained age as the time variable.

  • §Multivariable HRs are based on the age-adjusted model, additionally adjusted for level of total physical activity, height, energy intake, smoking, education, and county of residence.