P81 Investigating the relationship between green and blue spaces on maternal health and birth outcomes in Wales and Merseyside: a study protocol

Background

In recent years, the vital role Green and Blue Spaces (GBS) plays in community health has never been more apparent. However, the positive effects of GBS exposure on maternal health outcomes remains unclear. Moreover, the majority of studies that investigate this relationship have been cross-sectional in nature. Thus, this study aims to identify the impacts of GBS access and exposure on neonatal and maternal health outcomes in Wales and Merseyside. This study will utilise a natural experiment research structure that will allow for better understanding of the correlation between GBS and maternal outcomes. The objectives include creating longitudinal individual-level data linkages between GBS and maternal health data for the study population. The linked datasets will be utilised to address the question, does different exposure to GBS through time result in changes in risks of negative maternal outcomes? Additionally, is the association between changes in GBS exposure and maternal outcomes modified by socio-economic factors?

Methods

This study is a population wide longitudinal study. Data to be used will build upon an existing study; the protocol of which has been previously outlined (Mizen A et al, 2019). The proposed outcomes will be low birthweight (LBW), pre-term birth, common mental illness during antenatal and postnatal phase, pre-eclampsia, and gestational diabetes mellitus (GDM). Information will be derived from routine health data. The exposure measures will be looking at proximity and access to GBS based on an individual’s residential Lower Super Output Area (LSOA). Exposure measures will be derived using Geographic Information System (GIS) data to calculate annual mean enhanced vegetation indices (EVI) within buffer zones such as 300 m. Blue space exposures will be determined based on proximity to coastal or inland water. Comparisons will be made against unexposed women or women exposed to the lowest level of GBS. A joint modelling approach with a logistic regression model will be used. Co-variates that will be including in the analysis are socio-demographic factors such as deprivation and ethnicity. The study population in Wales will be limited to 2008 to 2018 and sourced from the Secure Anonymised Information Linkage (SAIL) databank. Merseyside data will be sourced from the Combined Intelligence for Population Health Action (CIPHA) databank.

Rationale

The research is novel due to the natural experiment design while other studies in this area are often cross-sectional. This study will serve to resolve conflict in the literature on the protective effects of GBS on maternal health. N/A