Impact of Alcohol-Induced Facial Flushing Phenotype on Alcohol Consumption among Korean Adults: A Two-Year Cross-Sectional Study.

Abstract

Alcohol-induced facial flushing phenotype (flushing) is common among East Asians. Despite a small intake of alcohol, they experience heightened levels of acetaldehyde, a group-1 carcinogen, which in turn causes unpleasant symptoms such as redness, acting as a robust protective mechanism against consuming alcohol. However, some individuals with this genetic trait exhibit weakened alcohol restraint, which increases the risk of developing alcohol-related cancers, such as esophageal and head/neck cancer, by more than ten times. Although this flushing phenomenon is crucial for public health, there is a paucity of studies that have comprehensively investigated the effect of flushing or its genotype on alcohol consumption in a large group of East Asians while controlling for various sociodemographic and health-related variables at a country level. This two-year cross-sectional study aimed to explore the effect of flushing on drinking behavior in Koreans and to examine whether the effect varies across sociodemographic and health-related factors. We used data from the Korea National Health and Nutrition Examination Survey 2019-2020 conducted by the Korea Disease Control and Prevention Agency. Our sample comprised 10,660 Korean adults. The study investigated the association of 26 variables, including flushing, with drinking frequency and amount. The effect of flushing was examined with and without adjusting for the other 25 variables using multinomial logistic regression analysis. Additionally, we tested the interaction effect with flushing and conducted a simple effect analysis. To ensure unbiased results, we employed complex sample design elements, including strata, clusters, and weights, to obtain unbiased results for the Rao-Scott χ2 test, t-test, and multinomial logistic regression analysis. The suppressive effect of flushing was significant across all pronounced categories of alcohol consumption at the significance level of .001 in 2019. The ranges of the standardized regression slopes and odds ratios were -6.70 ≥  ≥ -11.25 and 0.78 ≥ OR ≥ 0.50 for frequency; -5.37 ≥  ≥ -17.64 and 0.73 ≥ OR ≥ 0.36 for amount, respectively. The effect became somewhat stronger when adjusted for confounders. The effect also exhibited an overall stronger trend as the severity of alcohol consumption increased. The betas and odds ratios were consistently smaller in 2020 compared to the previous year. A simple effect analysis revealed a diminished alcohol-suppressive effect of flushing on alcohol consumption for specific groups (e.g., those with low levels of education, limited family support, physical labor, or health-related issues). Our findings suggest that flushing suppresses drinking in Koreans overall but has little or no effect in certain vulnerable populations. Therefore, health authorities should conduct targeted epidemiological studies to assess drinking patterns and disease profiles, particularly regarding alcohol-related cancers, and establish effective preventive measures tailored to this population.