Higher levels of alcohol consumption appear to increase an individual’s risk of early-onset colorectal cancer (CRC), particularly distal colon and rectal cancers, according to a population-based study from Korea.
The investigators retrospectively compared average daily alcohol consumption with early-onset CRC risk among nearly 5. 7 million adults younger than 50 years, using data from the Korean National Health Insurance Service
Alcohol consumption levels were defined as nondrinker, light, moderate, and heavy.
The primary outcome was incidence of early-onset CRC diagnosed before age 50. Models were adjusted for age, sex, smoking status, exercise, and income, as well as for comorbidities.
Overall, 8314 incident early-onset CRC cases occurred during the mean follow-up period of 7.4 years. Compared with light drinking, moderate and heavy drinking were associated with a significantly elevated risk of early-onset CRC (adjusted hazard ratio, 1.09 and 1.20, respectively); by sex, significant associations were found only among men.
Among men, heavy drinking vs light drinking was associated with a 26 per cent increased risk of distal colon cancer, a 17 per cent higher risk of rectal cancer, and a 29 per cent higher risk of unspecified colon cancer (but not proximal colon cancer).
Among women, moderate drinking was associated with a 47 per cent increased risk of distal colon cancer. Among nondrinkers, there was a 14 per cent reduced risk of rectal cancer compared with light drinkers.
“This population-based study provides evidence that higher levels of alcohol consumption may increase the risk of early-onset CRC,” the investigators concluded. “[E]ffective interventions are required to discourage alcohol consumption among young people and to tailor CRC screening approaches for high-risk individuals.”
The study led by researchers at Seoul National University, South Korea, was published online June 14 in the Journal of Clinical Oncology.
Study limitations include self-reported alcohol consumption. Data were missing for a higher number of male participants and younger participants, and there was a potential problem related to multiple comparisons and confounders.
Only Korean individuals were included in the study, so larger studies involving various races are needed.
