The association between relative income and depressive symptoms in adults: Findings from a nationwide survey in Korea

Background: Subjective income inadequacy may be associated with poorer mental health as income comparisons with others can decrease feelings of happiness. This study investigated the association between relative income and depressive symptoms in Korean adults. Methods: Data from the 2017 Korea Community Health Survey were used. Relative income was measured by comparing household and community income. Household income was calculated using equalized household income and community income based on the mean income level of the 253 local communities. Relative income was categorized into the high (community < household), middle (community = household), and low (community > household) groups. Analysis was conducted through multivariate logistic regression analysis. Results: Of a total of 201,326 study participants, 12,508 (6.2%) individuals had depressive symptoms. Compared to the high relative income group, the middle [Odds Ratio (OR): 1.23, 95 percent Confidence Interval (CI): 1.16-1.29] and the low (OR 1.58, 95% CI 1.50-1.66) groups showed gradually higher likelihoods of depressive symptoms. Such differences were magnified in individuals with low absolute household income or with experiences of unmet need. Conclusion: Individuals with lower or equal household than community income had higher likelihoods of depressive symptoms, with such differences augmenting in those with low absolute income or experiences of unmet need. The findings infer the importance of monitoring individuals at poorer relative income standings in addressing mental health.