Burden of disease attributable to vitamin A deficiency in Iranian population aged less than five years: findings from the global burden of disease study 2010.

Background: Vitamin A deficiency (VAD) is considered as one of the most serious public health concerns in developing countriesand the leading cause of mortality in under-five-year-old children.A large number of young children and pregnant women especially in low-income, non-industrialized communities are more susceptible to VAD. This study aims to report the burden of disease (BOD) attributable to VAD in Iranian population aged less than 5 years by using data of the Global Burden of Disease (GBD) study 2010.

Methods: The GBD 2010 study calculated the proportion of deaths, years of life lost (YLLs), and years lived with disability (YLDs) and disability-adjusted life years (DALYs) attributable to VAD by using the comparative risk assessment (CRA). VAD defined as low serum retinol concentrations (plasma retinol concentration < 0.70 umole/L) among children aged less than five. The VAD outcomes consisted of mortality due to diarrhea, measles, malaria, neglected infectious diseases, morbidity due to malaria (children < 5 years), low birth weight and other perinatal conditions. Uncertainty in the estimates is presented as 95% uncertainty interval (UI).

Results: In 1990, there were 371 (95% UI: 166,665) DALYs due to VAD per 100,000 under five-year-old Iranian children in both sexes. The DALYs rate had a downward trend throughout the following years and reached to 76 (95% UI: 33-139)in 2010.The DALYs in children aged under 5 years was 378 (95% UI: 153-747) years for boys and 363 (95% UI: 148-692) years for girls in 1990 which fell to 79 (95% UI: 32-149) and 73 (95% UI: 29-138) in boys and girls in 2010, respectively. The rates of YLDs attributable to VAD changed in both sexes from 87(95% UI: 34-162) in 1990 to 46 (95% UI: 17-69) in 2010. The highest rate of YLDs attributed to VAD was observed in children aged 1-4. On the other hand, the YLLs were mostly in the 0-1-year-oldchildren in all years except 2010.

Conclusion: It was found that DALYs attributable to VAD in 1990, followed by a considerable reduction rate after a period of two decades, in 2010. Additional studies on the burden of diseases particularly at sub-national level with more accurate data are recommended.