Association between social vulnerability and suicide: A population-level study in Australia

BACKGROUND: Social vulnerability is likely to be predictive of how well individuals within regions are supported during adverse events such as natural disasters. We aimed to examine the association between social vulnerability and suicide to inform targeted suicide prevention strategies. METHODS: We obtained region-level data on suicide counts and population estimates from the Australian Institute of Health and Welfare, and the same level of data on social vulnerability to health impacts of climate change. We performed adjusted negative binomial regression analysis to examine the associations of social vulnerability index (and the 14 social domains that comprise the index) with suicide. RESULTS: Greater social vulnerability was marginally associated with lower suicide rates at the population level (Incidence Rate Ratio [IRR] 0.99, 95% Confidence Interval [CI] 0.97-1.00). When social domains were modelled individually, increasing vulnerability related to three domains (income and employment, education and social development, communication and transport infrastructure) was associated with a higher suicide rate. Opposite patterns were observed for increasing vulnerability to the domains of household composition, natural and built environment, emergency services, health services, government services, housing precarity, and livelihood/occupation. LIMITATIONS: Social vulnerability index misses indicators that are associated with suicide. CONCLUSIONS: Regions with greater social vulnerability experienced slightly lower suicide rates. However, regions with heightened vulnerability due to unemployment, low labour force participation, poverty, low school participation, low educational attainment, high income inequality, and inadequate access to communication and transport infrastructure had higher suicide rates, highlighting the need to address these population-level factors to reduce suicide.