Trend of socio-demographic index and mortality estimates in Iran and its neighbors, 1990-2015; Findings of the global burden of diseases 2015 study

Background: The Global burden of disease and injuries study (GBD 2015) reports expected measures for years of life lost (YLL) based on socio-demographic index (SDI) of countries, as well as the observed measures. In this extended GBD 2015 report, we reviewed total and cause-specific deaths and YLL for Iran and all its neighboring countries between 1990 and 2015. Methods: We extracted data from the GBD 2015 database. Observed YLL measures were calculated by multiplying the number of deaths by standard life expectancy at each age. SDI was a composite index, calculated based on income per capita, average years of schooling, and total fertility rate. The GBD world population was used for age standardization. Results: All-ages crude death rate in Iran reduced from 665.6 per 100,000 population (95% uncertainty interval: 599.3–731.6) in 1990 to 487.2 (414.9–566.1) in 2015. The ratio of observed to expected YLL (O/E ratio) for all-causes ranged between 0.54 (Turkey) and 1.95 (Russia) in 2015. For Iran, the all-causes O/E ratio was less than 1 in all years (19902015), except 2003. However, cause-specific O/E ratio was more than 1 for some causes, including the top leading causes of YLL (ischemic heart disease, road injuries, and cerebrovascular disorders). Ischemic heart disease was the first or second cause of YLL in all comparator countries except Afghanistan. Conclusion: The leading YLL causes with high O/E ratios should be prioritized in public health efforts. In addition to research evidence, countries with low O/E ratios should be scrutinized to find feasible innovative interventions.