BACKGROUND: Our aim was to measure income-related inequality in completed suicides across provinces of Iran.
METHODS: This ecological study was performed using data of Urban and Rural Household Income and Expenditure Survey-2010 conducted by Iranian Centre of Statistics, and the data of completed suicides from Iranian Legal Medicine Organization in 2012. We calculated the Gini coefficients of per capita income and completed suicide rates, and the concentration index for per capita income inequality of completed suicides, across different provinces of Iran.
RESULTS: The Gini coefficients of per capita income and completed suicide rate in provinces of Iran were 0.0994 (95% CI = 0.0638 to 0.1349) and 0.3393 (95% CI = 0.2148 to 0.46338), respectively. We found a trivial decreasing trend in the completed suicide incidence rates in relation to income quintiles. The poorest to richest rate ratio was 2.015 (95% CI = 1.26 to 3.22). The concentration index of completed suicide in provinces of Iran was -0.1175 (95% CI = -0.2973 to -0.0623).
CONCLUSION: We found a roughly constant reverse association between completed suicide rates and per capita income in provinces of Iran. This study found that lower income might be considered as an important risk factor for this phenomenon. Nonetheless, further studies accompanied with multivariable analysis and repeated cross-sectional data are appreciated to delicately monitor over time.