Socioeconomic inequalities in suicidal ideation, parasuicides, and completed suicides in South Korea

As a result of unprecedented increase in suicides over the last decade, Korea now ranks at the top of OECD countries in suicide statistics (26.1 deaths per 100,000 population in 2005). Our study sought to document socioeconomic inequalities in self-destructive behaviors including suicidal ideation, parasuicide, and completed suicide. For prevalence of suicidal ideation and parasuicide, we used four waves of data from the Korea National Health and Nutrition Examination Survey (1995, 1998, 2001, and 2005). For suicide mortality, we abstracted suicide cases from the National Death Registration records, and linked them with population denominators from the national census in 1995, 2000, and 2005. We examined variation in self-destructive behaviors according to level of educational attainment (at the individual level), as well as area-level characteristics including level of deprivation and degree of urbanicity. Age-standardized rates were calculated through direct standardization using the 2005 census population as the standard. Inequalities were measured by the relative index of inequality and the slope index of inequality. The age-standardized prevalence of suicidal ideation decreased across consecutive surveys in both genders (18.0-13.5% for men, 27.5-22.9% for women). Parasuicides similarly decreased over time. By contrast, completed suicides increased over time (20.9-42.8 per 100,000 for men and 8.9-20.9 for women). The most prominent increases in completed suicides were observed among the elderly in both genders. Lower education, rural residence, and area deprivation was each associated with higher suicide rates. Both absolute as well as relative inequalities in suicide by socioeconomic position widened over time. Our findings suggest that the current suicide epidemic in Korea has social origins. In addition to clinical approaches targeted to the prevention of suicides in high risk individuals, social policies are needed to protect disadvantaged populations at risk of self-destructive behaviors.