Socio-demographic and economics factors associated with suicide mortality in Iran, 2001-2010: application of a decomposition model

Suicide is a major global health problem, especially among youth. Suicide is known to be associated with a variety of social, economic, political and religious factors, vary across geographical and cultural regions. The current study aimed to investigate the effects of socioeconomic factors on suicide mortality rate across different regions in Iran. The data on distribution of population and socio-economic factors (such as unemployment rate, divorce rate, urbanization rate, average household expenditure etc.) at province level were obtained from the Statistical Centre of Iran and the National Organization for Civil Registration. The data on the annual number of deaths caused by suicide in each province was extracted from the published reports of the Iranian Forensic Medicine Organization. We used a decomposition model to distinguish between spatial and temporal variation in suicide mortality. The average rate of suicide mortality was 5.5 per 100,000 population over the study period. Across the provinces (spatial variation), suicide mortality rate was positively associated with household expenditure and the proportion of people aged 15-24 and older than 65 years and was negatively associated with the proportion of literate people. Within the provinces (temporal variation), higher divorce rate was associated with higher suicide mortality. By excluding the outlier provinces, the results showed that in addition to the proportion of people aged 15-24 and older than 65, divorce and unemployment rates were also significant predictors of spatial variation in suicide mortality while divorce rate was associated with higher suicide mortality within provinces. The findings indicate that both spatial and temporal variations in suicide mortality rates across the provinces and over time are determined by a number of socio-economic factors. The study provides information that can be of importance in developing preventive strategies.