Indigenous suicide rates in the United States, Australia and New Zealand between 2006 and 2019

Objective: Indigenous suicide prevention is an important focus for national health policies. Indigenous suicide rates in formerly colonial English-speaking countries such as the United States, Australia and New Zealand are considerably higher than the general population, particularly in young males. Given the similarities in their sociocultural history, a time series analysis was conducted to assess recent sex and age trends of suicide in the Indigenous and general populations in the United States, Australia and New Zealand. Methods: Using the number of deaths by intentional self-harm and estimated resident population, suicide incidence rates were calculated for the years 2006-2019 and stratified by Indigenous status, year, time period, sex and age group (above 15 years). Incidence rates were plotted. Using the Poisson regression model, calculated suicide incidence rate ratios were used to make comparisons for sex and age. Results: Across all countries studied, Indigenous suicide rates have increased over time, with Indigenous males having higher suicide rates than Indigenous females. However, the increase in Indigenous female suicides was greater than that for Indigenous males in Australia and New Zealand. Indigenous males aged 15-44 years have the highest suicide rates across all countries. Conclusion: Indigenous suicide rates have remained consistently high in the United States, Australia and New Zealand, with Indigenous males aged 15-44 years showing the highest rate. However, suicide rates for Indigenous females in Australia and New Zealand are increasing more rapidly than males. Given this, it is critical that further research is dedicated to understanding and addressing the issues driving this problem, particularly in youth.