Income disparity and mortality among patients with alcohol use disorder in South Korea

Problems related to alcohol consumption, particularly alcohol disorders, occur frequently in South Korea and are gradually increasing due to the drinking culture and social atmosphere. We analyzed the relationship between mortality and income among patients with alcohol disorders. We used data from the National Sampling Claim Data 2003-2013, which included medical claims filed for 10,593 patients newly diagnosed with alcohol disorders. We performed survival analyses using a Cox proportional hazards model. 12.79% died during the study period. Patients with lower incomes were more positively associated with the risk of mortality than those with higher incomes (0-30 percentile: hazard ratio [HR] = 1.432, 95% confidence interval [CI] = 1.155-1.777; 31-60 percentile: HR = 1.318, 95% CI = 1.065-1.633; 61-90 percentile: HR = 1.352, 95% CI = 1.097-1.665; 91-100 percentile: ref). Such associations were significant in males, patients with mild conditions, or those who lived in metropolitan areas. In conclusion, we found that income disparity was related to mortality among patients diagnosed with disorders due to alcohol use. Thus, healthcare professionals need to provide active intervention in the early phase of alcohol disorders, and consider policy that would improve healthcare accessibility for low-income populations in order to reduce income disparity.