Influence of sex on the incidence of colorectal cancer: considering the influence of gender mechanisms

Context

Differences in colorectal cancer (CRC) incidence between men and women are documented, but the role of gender mechanisms in explaining these disparities remains underexplored. CRC, the third deadliest cancer worldwide, is often analyzed through “biological” sex differences, without a clear distinction between innate and socially acquired factors. Gender mechanisms, including social roles, behaviors, and access to healthcare, may significantly influence CRC risk.

Objective

This study quantifies the proportion of the effect of gender mechanisms on the relationship between sex assigned at birth and CRC incidence, adopting a social epidemiology approach.

Method

Using data from the CONSTANCES cohort and the French National Health Insurance database (SNDS), we identified relevant covariates with a Directed Acyclic Graph (DAG). Mediation analyses estimated the contribution of socioeconomic, behavioral, anthropometric and medical factors as gender-related mechanisms.

Results

Men have a higher risk of CRC compared to women (OR: 1.54 [1.33; 1.79]). Men exhibit lower cultural capital, higher social and economic capital, more frequent risk behaviors, and higher BMI. Gender mechanisms account for 30 % of the association between sex assigned at birth and CRC incidence, in the imputed data, and up to 50 % in the complete cases. Among the gender mechanisms, BMI emerged as the main mediator.

Conclusion

This study reveals that gender-based health inequalities in CRC incidence are partially explained by differences in exposure to social and behavioral risk factors. These findings underscore the importance of integrating gender dynamics into public health strategies for CRC prevention and intervention, focusing on addressing gender-based risk factor exposure.