Descriptive study on neural tube defects in Argentina

Neural tube defects (NTDs) are the most common congenital anomalies of the central nervous system. Prevalence of NTDs varies depending on geographic region and folic acid fortification. The main objectives of this study are to analyze the prevalences of NTDs reported to the National Registry of Congenital Anomalies of Argentina (RENAC) during the period 2009 to 2013, to compare them with data from other selected surveillance systems of the Americas, and to evaluate the impact of folic acid fortification on the prevalence of NTDs in Argentina.

We analyzed changes in prevalence between 2009 and 2013 for the RENAC, and differences in prevalence between RENAC and other surveillance systems. We evaluated changes for the pre and postfortification time periods in Argentina.

In Argentina, anencephaly and spina bifida showed no statistically significant variation between 2009 and 2013, and encephalocele showed a statistically significant decline. The RENAC showed a statistically significant higher prevalence for all three defects when compared with surveillance systems from Chile, Colombia, and Costa Rica, and a statistically significant lower birth prevalence than Cuba for anencephaly. No differences were observed when comparing it to the Atlanta-USA and Mexico systems. A significant decrease in prevalence was observed for all three anomalies for the postfortification period in Argentina.

The characteristics of cases reported to the RENAC are similar to those already reported in the literature. The differences in prevalence between the RENAC and other surveillance systems could be artifactual or real. We confirmed the decrease of prevalence of NTDs after folic acid fortification.