Risks of colon and rectal adenomas are differentially associated with anthropometry throughout life: the French E3N prospective cohort.

BACKGROUND: Associations between adult anthropometry and risk of colorectal neoplasms are well established. However, whereas body mass in infancy and childhood has been associated with risk of some cancers, little is known about potential associations with colorectal neoplasms. The authors investigated associations between colorectal adenoma risk and lifetime anthropometry, in an attempt to better understand the relationships between anthropometric features and colorectal carcinogenesis.
METHODS: Among the 17 391 women of the French E3N cohort who underwent a colonoscopy during follow-up (1993-2002), 1408 developed a first colorectal adenoma. Associations were estimated with Cox multivariate proportional hazard regression models.
RESULTS: Left colon adenoma risk was associated with high birth weight [hazard ratio (HR) high vs median = 1.21; 95% confidence interval (95% CI): 1.00-1.47, P(trend) = 0.03] and large adult body shape (HR = 1.28; 95% CI: 1.04-1.56, P(trend) = 0.02). A large versus small body shape at age 8 years and at menarche were associated with a decreased rectal adenoma risk [HR = 0.68; 95% CI: 0.49-0.95, P(trend) = 0.01 and 0.73 (0.53-1.01), P(trend) = 0.05, respectively]. Except for a positive association with large vs median birth weight, no anthropometric characteristic was associated with right colon adenoma risk. Associations did not differ between advanced and non-advanced adenomas.
CONCLUSIONS: These findings suggest that early life events may influence early stages of colorectal carcinogenesis and add to the evidence of differential pathways of carcinogenesis in the right colon, left colon and rectum.