A GIS-based approach to assess the influence of the urban built environment on cardiac and respiratory outcomes in older adults

The impact of the urban built environment on cardiovascular and respiratory health has been studied extensively in children and adults. However, limited research exists on this topic in older adults. To fill this gap, we conducted a ten-year retrospective study of a cohort of elderly people living in Lausanne. We extracted cardiac and respiratory health outcomes of people living at the same address. A geographic information system (GIS) application was used to join spatial data between participant address and characteristics of the built environment (building age, building density, road density, proximity to vegetation and lake, elevation). To capture the impact of the urban landscape characteristics on the health of older people, the built environment descriptors, were considered alone and aggregated. Principal component analysis (PCA) was employed to resolve the multicollinearity among the built environment descriptors, while agglomerative hierarchical clustering was used to reveal underlying patterns and relationships within built environment variables. In addition, to better assess the effectiveness of ventilation in their homes, we characterized indoor air -associated mycobiomes in a representative sample of homes. This involved employing both culture -based methods and metabarcoding of the first internal transcribed spacer (ITS1) of the ribosomal DNA. The analysis revealed a significant association between exposure to the built environment as a whole and heart disease in the elderly. A higher prevalence was observed for the cluster of buildings near the lake/highway. The period of building construction showed an association with the prevalence of chronic lung disease and chronic cough, with a higher prevalence observed in houses built between 1975 and 2013. The contribution of indoor air pollution to worsening respiratory health was confirmed by higher Aspergillus spore loads and increased relative abundance of Gloeophyllum and Aureobasidium in indoor air, all of which were associated with respiratory outcomes. This research highlights the crucial influence of the built environment on the health status of the elderly population, with implications for targeted interventions and public health policy development.