In recent years, extreme temperatures have gained significant attention in urban studies, leading to the search for various adaptation and mitigation measures. While many studies employ heat-related indicators to assess climate-related health impacts, a better understanding of the multi-dimensional nature of these indicators can enhance their integration into urban policies, planning and design. This research aims to examine various dimensions of urban heat stress in built environments, using a systematic review of scientific articles (n = 146) and consequently, establishing a framework for effectively stratifying examples of related indicators across different dimensions. The results showcase dimensions including demographic, economic, health, urban climate, social, urban morphology, and institutional. However, literature disproportionately emphasizes demographic, health and climate dimensions, while social, urban morphology and institutional ones receive comparatively less attention. On the other hand, the co-occurrence analysis reveals connections among these dimensions and their related indicators, underlining the need for a holistic understanding of heat stress impacts. Additionally, the spatial distribution of the selected papers brings attention to the lack of studies in the regions identified as most exposed according to the Koppen Climate Classification. Accordingly, we advocate for more multidimensional and context-specific studies that bridge existing gaps. This research provides valuable insights for policymakers, planners, urban designers and researchers on advancing the understanding of urban heat stress in built environments and its impact on urban healh.

In recent decades, the increasing frequency, intensity, and duration of heatwaves generated by climate change has posed significant challenges to public health, particularly in urban areas. Despite extensive research on the impacts of heatwaves on human health, there is still a need for enhanced understanding of how, and to what extent, the spatial attributes of urban environments exacerbate these effects at the very local scale. This research addresses this gap and emphasises the importance of analysing the relationship among urban form, climate and health through high resolution geo-spatial data. By investigating the spatial correlations between geolocated cardiovascular and respiratory emergency calls, the modelled universal thermal climate index (UTCI) and selected socio-demographic factors during the summer of 2022 in Milan, this study aims to enhance our understanding of the complex interaction among heat, the built environment, and specific health outcomes. The findings identify geographical locations where emergency calls occur more frequently and where health concerns emerge during hot spells. Morphological and socio-demographic factors both play a critical role in determining vulnerability to heat stress. The results provide valuable insights for identifying high-risk areas, where tailored interventions in terms of planning, governance and urban design may be implemented to address heat-resilience and health-equity in cities.