Alcohol use is a known risk factor for gastrointestinal (GI) cancers. Now, new research indicates that this risk is more associated with frequent drinking – even in smaller amounts – compared with higher amounts or binge drinking, given similar weekly levels.
“The novel finding of the current study is that frequent drinking may be more dangerous than binge drinking with regard to GI cancers. Alcohol use is a known risk factor for gastrointestinal (GI) cancers. Now, new research indicates that this risk is more associated with frequent drinking – even in smaller amounts -- compared with higher amounts or binge drinking, given similar weekly levels.” first author Jung Eun Yook, MD, of Seoul (South Korea) National University Hospital, and colleagues reported in an article published Aug. 18, 2021, in JAMA Network Open (doi: 10.1001/jamanetworkopen.2021.20382).
“This finding suggests that repeated alcohol consumption events even at lower amounts of alcohol may have a greater carcinogenic effect on GI organs than the consumption of larger amounts of alcohol at a lower frequency,” the investigators wrote.
A possible reason behind the difference in risk may be that the chronic “carcinogenic insult” from regular alcohol use may promote cancer development, whereas less frequent, episodic alcohol exposures may allow physiologic recovery, said the authors.
The results are from a population-based study that involved 11,737,467 participants in the Korean National Health System database who did not have cancer and who took part in a national screening program between January 2009 and December 2010.
They were followed from the year after their screening until either they had received a diagnosis of a GI cancer, death occurred, or the end of December 2017.
During a median follow-up of 6.4 years, 319,202 (2.7%) of those in the study developed a GI cancer.
The increase in the risk associated with alcohol consumption was dose dependent.
Compared with those who did not consume alcohol, the risk of developing GI cancer was higher for mild drinkers (adjusted hazard ratio, 1.04; 95% confidence interval, 1.03-1.05), moderate drinkers (aHR, 1.14; 95% CI, 1.12-1.15), and heavy drinkers (aHR, 1.28; 95% CI, 1.26-1.29), after adjusting for age, sex, income, smoking status with intensity, regular exercise, body mass index, diabetes, hypertension, and dyslipidemia.
There was a linear association between the frequency of drinking and GI cancer risk, with an aHR of 1.39 for individuals who reported drinking every day (95% CI, 1.36-1.41). The risk for GI cancer increased with consumption of five to seven units per occasion (aHR, 1.15). Notably, there were no similar increases with higher intake, including intake of 8-14 units per occasion (aHR, 1.11; 95% CI, 1.09-1.12), and even up to more than 14 units per occasion (aHR, 1.11; 95%CI, 1.08-1.14), in comparison with an intake of 5-7 units per occasion.
“Given similar weekly alcohol consumption levels, the risk of GI cancer increased with a higher frequency of drinking and decreased with a higher amount per occasion,” the authors write.
“Most previous studies just assess alcohol consumption as a total amount, [such as] drinks per occasion times occasion per week equals drinks per week [and] grams per week,” coauthor Dong Wook Shin, MD, DrPH, Samsung Medical Center, Sungkyunkwan University, Seoul, South Korea, said in an interview.
“But it was not known whether frequent drinking with small amount is more harmful than binge drinking, given a similar level of total drinking,” Dr. Shin said.
The increased risk associated with frequent drinking was generally similar with respect to esophageal, gastric, colorectal, biliary, and pancreatic cancer.
An exception was liver cancer, which showed a slightly decreased risk among mild drinkers (aHR, 0.91; 95% CI, 0.89-0.93).
Of note, the association between alcohol intake and the incidence of GI cancer was lower among women than men in terms of weekly consumption, frequency, and amount of alcohol consumed per occasion.
The associations between drinking and cancer type in terms of esophageal and liver cancers were similar between men and women. However, the alcohol-related risk for colorectal, biliary, and pancreatic cancers was less prominent for women.