Approved Research

Combined effects of healthy lifestyle factors for early-onset colorectal cancer incidence and mortality

Lay summary

Over the past decades, although the overall incidence and mortality of colorectal cancer trends have been declining among the entire population, an increasing trends in the incidence of early-onset colorectal cancer (age!50 years) was recently observed. However, the reason for rising EOCRC incidence and mortality are unclear. EOCRC tumors are different from traditional colorectal cancer in clinical, pathological, and molecular. Currently, a comprehensive analysis of the impact of environmental risk factor on EOCRC based on case-control studies or cohort studies is lacking. In addition, colorectal cancer is a multifactorial disease, requiring a combination of exposures for its development. Single environmental factor is not enough to clarify the interaction between different risk factors. Some risk factors are highly correlated, which is difficult to distinguish their independent effects.

The study purposes are as follows: (1) To estimate the impact of individual lifestyle factors (e.g. body mass index, cigarette smoking, alcohol consumption, physical activity, aspirin use, antibiotics use, and diet factors such as daily intake of fruit/vegetables, daily intake of red and processed meat, daily intake of milk) on early- onset colorectal cancer (EOCRC) incidence and mortality. (2) To assess the combined effects of the healthy lifestyle factors on EOCRC incidence and mortality through using a combined exposure score method based on the number and level of risk factors to which each participant was exposed. (3) To examine whether the impacts of lifestyle factors for EOCRC is different from that of late-onset colorectal cancers.

The estimated duration of this project is 12 months. This study will identify potential risk factors for EOCRC morbidity and mortality, and evaluate the impact of combined healthy lifestyle factors on EOCRC morbidity and mortality. This information could be used by general and high risk population to prevent EOCRC and help to develop prevention and screening strategies.