Geospatial and Temporal Clustering of Folic Acid- Sensitive Congenital Defects in Villa Clara Province, Cuba

Abstract

Introduction: Geospatial and temporal clusters are defined as the occurrence of an unusual number of cases higher than expected in a given geographical area in a certain period of time.Objectives: to determine the birth prevalence rate of birth defects sensitive to folic acid deficiency and to identify, describe, and characterize potential geospatial and temporal clusters of these birth defects in Villa Clara province, Cuba. Methods:The cases were ascertained from 46 007 total births, record of 267 cases with prenatal or postnatal diagnosis of five folic acid-sensitive selected birth defect were acquired based on hospital registers and community based registers too. Spatial scan statistic was used to determine areas of the province with spatial and temporal clusters for the birth defects sensitive to folic acid deficiency under study. Results:The overall adjusted birth prevalence was 58.0 per 10 000 births. The highest prevalence rate occurred in conotroncal heart defects, followed by Down syndrome and neural tube defects, meanwhile orofacial clefts and gastroschisis shown the lowest prevalence rates. Overall, the prevalence of folic acid-sensitive congenital defects under study declined over the six years of the study. A primary spatial and spatio-temporal cluster for the birth defects under study was identified in two neighboring municipalities and secondary spatial clusters were identified in another three municipalities. Conclusion:Identification of birth defects geospatial clusters must be faced recognizing that such challenge is in fact an opportunity to achieve a better knowledge of causes of these birth defects.