Open Access Research BMJ Open: first published as 10.1136/bmjopen-2015-009451 on 23 December 2015. Downloaded from Changes in South Korean urbanicity and suicide rates, 1992 to 2012 Chee Hon Chan,1,2 Eric D Caine,3,4 Sungeun You,5 Paul Siu Fai Yip1,2 To cite: Chan CH, Caine ED, ABSTRACT et al Strengths and limitations of this study You S, . Changes in Objectives: Studies have highlighted the association South Korean urbanicity and between the degree of urbanicity and spatial disparities ▪ suicide rates, 1992 to 2012. This is the first study addressing the temporal in suicide, but few have evaluated its changes across BMJ Open 2015;5:e009451. changes of the geographical patterning in suicide doi:10.1136/bmjopen-2015- time. We explored the geospatial trends of suicide in among all the population in South Korea. 009451 South Korea from 1992 to 2012, and their relationship ▪ The results of this study were based on a large to the nation’s evolving urbanicity. national representative sample with the observa- Setting: South Korea. ▸ Prepublication history tory period lasting for 21 years. and additional material is Primary outcome measures: Age-sex-specific ▪ Potential limitations include the use of an eco- available. To view please visit suicide rate. logical study design and changes in data quality the journal (http://dx.doi.org/ Results: Suicide rates increased in all regions of of the suicide statistics over the course of the 10.1136/bmjopen-2015- South Korea during the study period. Controlling the study period. 009451). effects of age and sex, there was an overall inverse ▪ This study highlights the profound changes in relationship between the degree of urbanicity and the geospatial pattern of suicides in South Korea Received 22 July 2015 regional suicide rates. These associations were, and its potential link with internal migration. Revised 30 September 2015 Accepted 9 November 2015 however, attenuated across the periods, as there were smaller increases in suicide rates in mid-sized urban regions as compared to larger cities and to rural areas. differences have reflected a relative decline Increases over time in the suicide rates among youth in urban areas.316Changes in spatial dispar- and working-age adults were greater in large urban ity of suicide also have been reported to vary centres and in rural regions. For elders, the increase by age and sex differences in population was far greater in rural regions. composition.3 Conclusions: The association of urbanicity and the Assessments of spatial trends in suicide geospatial pattern of suicide in South Korea was a rates are uncommon for Asian countries. dynamic process and varied by age groups across the Suzuki et al examined the spatial pattern of http://bmjopen.bmj.com/ course of two decades. Internal migration and related suicide in Japan at the prefecture level and social processes most likely contributed to these changes. found that the suicide rate of men in the rural region was greater. They also noted that 1Department of Social Work the urban–rural variation in men had and Social Administration, widened from 1975 to 2005.17 Chen et al18 in The University of Hong Kong, Taiwan reported that the suicide rate of Hong Kong INTRODUCTION 2Hong Kong Jockey Club those in rural areas decreased at a faster Centre for Suicide Research Cross-sectional studies have highlighted that pace than those of their urban counterparts on October 1, 2021 by guest. Protected copyright. and Prevention, suicide rates differ greatly across geograph- during a period of overall decline; in con- The University of Hong Kong, ical regions in the same country, but that the trast, during a time of overall increase, the Hong Kong fi 3 nature of such ndings are inconsistent. rate rose more quickly in urban communi- Injury Control Research 18 Center for Suicide Prevention While some studies have noted higher ties. In South Korea, various cross-sectional 1–5 and Department of suicide rates in urban settings, others have investigations have shown a higher suicide 19–21 Psychiatry, University of reported that risks for suicide are relatively rate among rural residents. Two recent – Rochester Medical Center, greater among rural dwellers.6 12 Studies Korean studies found that suicide rates Rochester, New York, USA 4 have also highlighted that the geospatial among more economically deprived areas VA Center of Excellence for 12 22 23 Suicide Prevention, inequalities in suicides changed across time. were higher. With one exception, few Canandaigua, New York, USA In some developed Western countries (eg, have explored the geospatial trend of suicide 5Department of Psychology, Australia, Austria, England and Wales, and in South Korea. Chungbuk National the USA), spatial disparities in suicide rates Contextual factors, such as urban growth University, Republic of Korea have grown due to greater relative increases and internal migrations, have been proposed Correspondence to among rural residents as compared with to affect the association between urbanicity 4513–15 13 24 Dr Chee Hon Chan; their urban counterparts. Other and suicide rates. In Australia and the [email protected] studies have suggested that such spatial UK, decline in the rural economies together Chan CH, et al. BMJ Open 2015;5:e009451. doi:10.1136/bmjopen-2015-009451 1 Open Access BMJ Open: first published as 10.1136/bmjopen-2015-009451 on 23 December 2015. Downloaded from with an out-migration of healthier individuals to urban population estimates, stratified by age (5-year age band), settings have been suggested to contribute to increased sex and administrative districts, as well as official district – suicide rates among young adults in rural areas.25 27 In level maps released by the Statistical Geographic Asian countries where the social welfare infrastructure is Information Service of Statistics Korea. The earliest avail- less developed, a high level of material deprivation has able population estimates by district occurred in 1992; been reported to increase rural dwellers’ suicide risk.69 hence, our study covered a 21-year study period (from Among aged populations, social isolation or social disin- 1992 to 2012). We retrieved for the study period 133 456 tegration (eg, loneliness and breaks in family ties) also and 63 721 suicides among men and women, respect- have been noted to increase suicide vulnerability.14 28 29 ively, having valid information regarding their residential Additionally, rural residents have less access to health- address coded at the administrative district level. care services, and often use highly lethal methods (par- ticularly agricultural pesticides) when attempting to kill Geographical system of South Korea and the population themselves.518 distribution within the study period During recent decades, the rapid economic growth The geographical system of South Korea has a hierarch- and societal modernisation occurring in South Korea ical structure. The highest level includes seven metro- has been associated with powerful sociocultural politan cities and nine provinces (do). Metropolitan changes, with intense urban growth and internal migra- cities are considered as larger urban areas with the – tions.30 32 Reports have revealed that, from the 1970s to highest population density. Provinces are partitioned the 2000s, more than 30 million Koreans had moved into either city (si) or smaller administrative districts from rural regions to urban centres and the percentage (gun) depending on population size. In this hierarch- of persons living in urban areas increased by 40%.30 33 ical geographical system, all metropolitan cities and During this process, economies in the rural regions several somewhat bigger cities are then partitioned into deteriorated due to the loss of workforce and the subdistricts (gu). During the study period, the South decline of family-based agriculture. Many families Korean government undertook a major reorganisation shrank from extended networks to nuclear groups, of its administrative districts. For instance, in 1995 the marked by diminished social roles for elders and weaker government integrated a number of small districts into intergenerational economic and emotional sup- nearby cities to enhance local development, and over ports.30 31 33 Several authors have suggested that the the course of ensuing years, many districts either have impact of such changes has fallen hardest on older split into smaller districts or merged into a city due to rural residents who hold more traditional values, with the growth of the population. According to official negative consequences for physical and mental maps, there were 270 South Korean administrative dis- – health.34 36 In turn, the population influx into urban tricts (si, gu or gun) in 1992, which were reduced to settings led to overcrowding, housing shortages and a 251 by 2012. deteriorating living environment. Recent reports have To allow a direct comparison of demographic and http://bmjopen.bmj.com/ indicated that some second-tier (mid-sized) cities have social trends and changes in suicide rates in each dis- been gaining in population, while levels in large metro- trict, we constructed a map having consistent boundaries politan areas (eg, Seoul and Busan) and rural regions over the 21-year study period, yielding 214 ‘consistent’ have been shrinking.30 37 districts. On the basis of these 214 ‘consistent’ districts, We conducted this study to assess whether these dra- we calculated the population density of each district matic, region-specific demographic shifts, with