Characterizing the climate risks, social vulnerability, and neonatal transport burden on neonatal intensive care units in the United States under 2°C and 50cm sea level rise

Abstract

IntroductionThe impacts of climate change are becoming more significant, leading to more extreme weather events across the United States, including extreme temperatures, flooding, and wildfires. Climate disasters can threaten healthcare access and induce hospital shut-downs, forcing relocation of patients, with the potential for serious health consequences for vulnerable populations like neonates in neonatal intensive care units (NICUs). Socially vulnerable populations also face a disproportionate burden of climate disasters and more limited healthcare access. Understanding which NICUs face risks from climate hazards and transport distances to other NICUs could enhance preparedness and response. This research aims to characterize the spatial distribution of climate risk, the relationship between social vulnerability and climate risk, and areas with a dual high transport burden per neonate and high climate risk. Methods Four publicly available datasets were used to conduct descriptive analyses identifying NICUs located in census tracts experiencing climate risks. 2023 NICU locations came from the Neonatology Solutions Directory. Climate risks under 2°C warming and 50cm sea level rise (SLR) from the US Environmental Protection Agency (EPA) were z-transformed and summed to create a total climate risk variable, and a linear regression assessed the association between Centers for Disease Control and Prevention’s (CDC) Social Vulnerability Index (SVI) and total climate risk, controlling for non-time-varying relationships. Such non-time-varying relationships include the state and geographic jurisdictional state. To model the scenario of a climate hazard resulting in a full NICU shutdown, Euclidean transport distances were calculated from longitude and latitude coordinates between NICUs of the same level or higher. Average transport distances per neonate were calculated for three bed capacity scenarios: 100% capacity at the sending NICU and 25, 50, and 75% capacity at the receiving NICU. A simulation was applied to reallocate neonates starting with the closest NICU available that was the same level or higher. Unadjusted linear regression was conducted between climate risk and average transport distance per neonate to identify NICUs with high climate risk and long transport distances. All analyses were conducted in R v2024.12.1+563. Results The analysis included 1,392 NICUs operating in 2023. The US South is projected to have the highest total climate risk; 12 NICUs are projected to have elevated climate risk as a result of risk for property inundation from coastal flooding. The 12 NICUs located in states with elevated climate risk include Texas, Florida, Maine, Louisiana, California, Virginia, North Carolina, South Carolina, and Georgia. There was no association between SVI and total climate risk. There were associations between total climate risk and average transport distance per neonate. For example, using the 25% capacity scenario a 1-unit increase in total climate risk was associated with 1.88 additional miles (95%: 0.36, 3.39) of transport distance, with the relationship strengthening with higher receiving NICU bed capacity scenarios (50%, and 75%). The top 10 NICUs with metrics in the top quartile for total climate risk and transport distances were identified, with 8 NICUs requiring neonates be transported >300 miles, on average. Conclusion Careful planning and tailored disaster mitigation for NICUs are critical, especially for NICUs with high climate risk and transport burden.