Income-related inequalities in the prevalence of depression and suicidal behaviour: a 10-year trend following economic crisis.

The issue of health inequalities has steadily gained attention in South Korea, as income inequality widened and social polarization increased following the country's economic crisis in the late 1990s. While official figures indicate a general trend of worsening mental health, with rapidly rising rates of suicide and depression in particular, the extent of socio-economic inequality with respect to mental health problems has not been well elucidated. This study aimed to measure income-related inequalities in depression, suicidal ideation and suicide attempts in South Korea and to trace their changes over a 10-year period (1998-2007). The concentration index approach was employed to quantify the degree of income-related inequalities, using four waves of the Korea National Health and Nutrition Examination Survey data. The study found persistent pro-rich inequality in depression, suicidal ideation and suicide attempts over the past decade (i.e., individuals with higher incomes were less likely to have these conditions). The inequalities actually doubled over this period. These findings imply a need for expanded social protection policies for the less privileged in the population.