Increased rate of total and cardiovascular congenital abnormalities in Brindisi: a legacy of environmental pollution?

Background: Total and cardiovascular congenital abnormalities are the most prevalent and fatal birth defects worldwide, result from a combination of genetic predisposition and environmental factors. Areas under high environmental pressure can expose offspring to higher risks of abnormalities. Aim-To validate and estimate diagnosed cases of total and cardiovascular congenital abnormalities from hospital discharge records among newborns and to compare the prevalences observed with those reported by the registries operating in Europe (EUROCAT). Methods: The diagnoses of the regional hospital claims, coded according to the International Classification of Diseases, 9th Revision, Clinical Modification, have been abstracted for newborns in the period 2001-2008. They have been validated with Intensive Therapy Neonatal Unit (UTIN) data base for the same period through a record linkage. In particular, the validity, sensitivity and specificity of the method were measured by individual-level comparisons with data in the UTIN, gold standard for its accuracy of diagnostic information. Results: For total and cardiovascular congenital abnormalities we estimated high sensitivity (69% and 80% respectively) and a specificity for both of almost of 100%. We recorded 195 congenital malformations in 6,596 newborns, accounting for a prevalence rate of 295.6/10,000 total births, approximately 1.5 times significantly higher than those reported by the EUROCAT registries. Significant excess were 51.9 and 157.1 for congenital abnormalities and cardiovascular anomalies, respectively. Conclusions: Our results support the hypothesis for a possible causal role of environmental risk factors present in the risk area on the etiology of malformation, especially for cardiovascular abnormalities. The findings also suggest the possibility to use the regional hospital claims to identify cases of congenital abnormalities and to estimate their occurrence in absence of a register