The prevalence of and factors associated with depressive symptoms in the Korean adults: the 2014 and 2016 Korea National Health and Nutrition Examination Survey.

PURPOSE: This study was performed to investigate the prevalence of and factors associated with depressive symptoms in the Korean adult population.

METHODS: 10,710 participants in the 2014 and 2016 Korea National Health and Nutrition Examination Survey (KNHANES) were analyzed in this study. Assessment of depressive symptoms was performed using the self-administered nine-item Patient Health Questionnaire (PHQ-9).

RESULTS: The weighted prevalence of clinically relevant depression (PHQ-9 score ≥ 10) in the Korean adult population was 6.1% [5.5-6.8%]. Female sex, adults aged 19-29 years, elementary school graduation, living alone were significantly associated with clinically relevant depression. Having a household income ≤ 24th percentile was associated with a 2.26 (CI 1.49-3.45, p < 0.001)-fold higher prevalence of clinically relevant depression compared to having a household income ≥ 75th percentile. Regarding occupation, treating managers and professionals as controls, we found that unemployed individuals (OR 2.36, 95% CI 1.52-3.65, p < 0.001) had an increased risk of clinically relevant depression. Alcohol consumption < 30 g/day was reversely associated with clinically relevant depression (OR 0.75, 95% CI 0.62-0.93, p = 0.007), when abstain from alcohol was treated as control. Current smokers (OR 3.42, 95% CI 2.54-4.60, p < 0.001) and ex-smokers (OR 1.73, 95% CI 1.24-2.42, p = 0.001) had a higher risk of clinically relevant depression than never-smokers.

CONCLUSIONS: The estimated prevalence of depressive symptoms in a representative sample of the Korean adult population was 6.1%. This study suggests that younger age, female sex, elementary school graduation, living alone, low household income, current smoking, and being unemployed are associated with depressive symptoms.