Demographic, birth, parental characteristics, and the risk of early-onset colorectal cancer: A population-based...

The incidence of early-onset colorectal cancer (EOCRC), defined as colorectal cancer diagnosed before the age of 50 years, has been increasing. The relationship between demographic, birth, and parental characteristics and risk of EOCRC has not been elucidated.

This study included 1221 cases born and diagnosed with EOCRC at the age of 0 to 39 years in California during 1988 through 2021 and 61,050 frequency-matched controls based on birth year. Odds ratios (OR) and 95% CIs were estimated using multivariable logistic regression models.

Based on multivariable analysis, males had 34% higher risk of EOCRC compared to females (OR = 1.34; 95% CI, 1.20-1.51), and Hispanic ethnicity was associated with 43% higher risk of EOCRC (OR for Hispanic versus non-Hispanic White = 1.34; 95% CI, 1.20-1.51). Having a foreign-born mother was associated with a lower risk of EOCRC (OR = 0.85; 95% CI, 0.73-0.97). Among females, every 500-g increase in birthweight was associated with 10% increase in EOCRC risk (OR = 1.10; 95% CI, 1.01-1.21) and having a father aged ≥35 years was associated with higher risk of EOCRC (OR = 1.56; 95% CI, 1.08-2.25). No other demographic, birth, and parental characteristic was significantly associated with risk of EOCRC.

High birthweight, male sex, Hispanic ethnicity, and older paternal age are potential risk factors for EOCRC. Maternal birthplace, which is associated with diet, smoking patterns, other health-promoting characteristics, may be protective against EOCRC. These factors require future research for validation and evaluation of possible mechanisms.