Anencephaly related infant mortality in Argentina: spatial and temporal analysis (1998-2007)

Abstract

Analyze the spatial and temporal distribution of infant mortality by anencephaly in Argentina in relation with folic acid fortification phases. Data came from certificates of live births and deaths in children under 1 year, for the 1998-2007 period (Argentine Ministry of Health). The infant mortality rate attributable to anencephaly for Argentina, geographical regions, provinces and departments were estimated according to the different phases of mandatory fortification with folic acid. Secular trend of infant mortality rate attributable to anencephaly and death risk due to anencephaly, spatial distribution by infant mortality rate attributable to anencephaly cluster and its correlation to latitude and longitude were also analyzed. Reduced risk of mortality due to anencephaly (53%) was observed at national level. The greatest decline occurred in Cuyo (69%) and lowest in the Northeast (35%) at regional level. Considerable infant mortality rate attributable to anencephaly heterogeneity was found at departmental level and less at provincial level. A cluster of 5.15/10 000 infant mortality rate attributable to anencephaly was identified in the northeast of Buenos Aires province, consisting of 29 departments, significantly different from the rest of the country. While there was a statistically significant negative secular trend of infant mortality rate attributable to anencephaly, spatial disparities persist. The geographical distribution of anencephaly would guide the search for environmental/ genetic risk factors and strengthen primary prevention strategies, through mandatory fortification, folate intake and folic acid supplementation.