Spatial association between socioeconomic variables and risk related to pre-term births in metropolitan region of Sao Paulo (MRSP) and Lisbon metropolitan area (AML)

Abstract

Preterm birth is a major public health problem, contributing greatly to childhood morbidity and mortality, both in developing countries like Brazil, as in European countries like Portugal. Preterm babies are those that born with less than 37 weeks of gestation. The individual risk factors associated with the incidence of prematurity are known. However, the contextual factors that may influence its incidence have been little studied. The present study aimed to identify the spatial pattern of relative risks of preterm birth and possible spatial clusters, as well as examine if the socioeconomic conditions are spatially associated with relative risks of preterm births in two different metropolitan areas: Metropolitan Region of São Paulo (MRSP), in Brazil, and the Lisbon Metropolitan Area (LMA), in Portugal. Data related with preterm births (2000-2010) and their mothers and socioeconomic conditions from both metropolitan areas were collected. For analysis of spatial association between the relative risk of preterm birth and geographical context variables, tests of overall spatial association (Moran I) for both metropolitan areas were applied. The geographical distribution of the relative risk of preterm births occurred not random and unevenly both in MRSP as in LMA: in the MRSP, there was only a significant global spatial association between relative risk and the unemployment rate; in LMA, there was a global significant association between the relative risk and the illiteracy rate, sociomaterial deprivation index and the unemployment rate.