Spatial analysis of suicide mortality in Australia: Investigation of metropolitan-rural-remote differentials of suicide risk across states/territories

Studies of suicide epidemiology in regions of Australia have been conducted, but the spatial pattern in the whole country has not been fully investigated. This study aimed at visualizing the sex-specific suicide pattern over the country from 2004 to 2008, and studying the metropolitan-rural-remote differentials of suicide across all states/territories. We applied a Poisson hierarchical model to yield smoothed sex specific, age standardized mortality ratios of suicide in all postal areas, and compiled the age-standardized suicide rates across different levels of remoteness and different jurisdictions. We identified the area variation of suicide risk across states/territories, and metropolitan-rural-remote differential with rates higher in rural and remote areas for males. Spatial clusters of some high risk postal areas were also identified. Socio-economic deprivation, compositional factors, high risks for Indigenous people and low access to mental health service are the underlying explanations of the elevation of suicide risk in some areas. These findings suggest that it is important to take geographical variations in suicide risk into account in national policy making. Particular suicide prevention interventions might be targeted at males living in remote areas, and some localized areas in metropolitan zones.