Objectives
To study the association between waist circumference and colorectal cancer, and whether it is independent of body mass index
(BMI).
Methods
Between 1997 and 2005, 953 incident colorectal cancer cases (546 men and 407 women) were identified among 95,151 participants
(44,068 men and 51,083 women) from the Cancer Prevention Study-II Nutrition Cohort.
Results
Waist circumference was associated with increased colorectal cancer incidence in both men (multivariable adjusted rate ratio
(RR) 1.68, 95% confidence interval (CI) 1.12–2.53 for waist circumference ≥120 cm compared to <95 cm, p trend = 0.006) and women (RR 1.75, 95% CI 1.20–2.54 for ≥110 compared to <85 cm, p trend = 0.003). High levels of BMI were also associated with increased risk. After adjustment for BMI, waist circumference
remained associated with a nonstatistically significant increase in colorectal cancer incidence in both men (RR 1.41, 95%
CI 0.81–2.45 for ≥120 compared to <95 cm, p trend = 0.10) and women (RR 1.48, 95% CI 0.89–2.48 for ≥110 compared to <85 cm, p trend = 0.13).
Conclusions
Our results confirm that waist circumference is associated with increased colorectal cancer incidence, possibly partially
independent of BMI.
Keywords Obesity - Central obesity - Waist circumference - Body mass index - Colon cancer - Rectal cancer - Colorectal cancer