Developing tools to support older adults during climate-related emergencies

Abstract

What makes a person more likely to experience adverse health outcomes caused by extreme weather events? Can we identify those individuals at high risk before an extreme event happens? Natural hazards can lead to death and physical injury, as well as non-specific psychological distress, post-traumatic stress disorder, depression, and anxiety. By now, we have a good understanding of the main outcomes and some group-level risk factors associated with these events, such as low socioeconomic status, certain health conditions, and older age. These risk-factors are often used to develop vulnerability indices that can identify people at risk of adverse outcomes during an extreme event. However, these indices can be highly inefficient because not all individuals within each group live with the same vulnerability. Thus, it is essential that we use real-time, clinical, and demographic information to identify individuals at risk before an extreme weather event happens instead of relying on general group membership. The goals of this thesis are a) to understand the risk and protective factors that place older adults at higher risk of adverse health outcomes caused by natural hazards, and b) to develop indices to identify those individuals at highest risk. To achieve these goals, the thesis uses clinical assessments and focuses on acute, short-term health complications often a result of heat-related events and wildfire smokes. The thesis is divided in 3 studies and all studies used data from the interRAI Home Care and interRAI Contact Assessment instruments, which are comprehensive assessments to evaluate the person’s health needs and strengths. Study 1 is an empirical investigation of the risk factors that place older adults at odds of living in homes with inadequate heating or cooling. The study uses longitudinal data and generalized estimating equations to explore risk factors such as demographic and social-economic characteristics as well as availability and quality of informal caregiver support for older adults with complex medical needs in Canada. These factors were used to identify geographic locations in Ontario with high percentages of home care clients living with inadequate heating or cooling at home. This is the first study that addresses the risks and protective factors associated with the thermal environment in home care clients, which is a population at high risk of adverse health outcomes during heat waves and cold spells. Study 2 presents a new index to identify individuals that could be at risk of health complications during extreme weather events. The Brief Risk Index (BRI) was derived from data elements present in a screener that supports home care intake from community and hospital. It focuses on items indicating that individuals receiving home care services would have difficulty evacuating their homes during a time of crisis (e.g., cognitive impairment and difficulty performing activities of daily living). When compared with another tool that has been used in real-life situations, the BRI showed similar performance but with less items. This is the first index that targets the whole home care population in Canada, not only those receiving long-term services. Therefore, the BRI can be a game changing in emergency preparedness because of its efficiency and large target population. Study 3 uses a similar approach as in Study 2 but focuses on home care clients at high risk of health complications caused by poor air quality. While the BRI is a more general tool, the Cardiorespiratory Vulnerability index (CRV) contains 16 items from a standardized assessment for home care clients and includes clinical characteristics often associated with negative health outcomes caused by poor air quality, such respiratory and heart diseases. This is the first index related to risks associated with air quality available in vulnerable populations in Canada, and one of the few worldwide. The study makes an important contribution to public health because climate change is accelerating the conditions under which wildfires and their adverse effects on air quality are more likely to happen. Identifying individuals at high risk before an extreme weather event happens is a pressing problem in our society. This is particularly important today because of our aging population combined with the increase of the frequency, duration, and severity of extreme weather events caused by climate change. This thesis advances our knowledge of the risk and protective factors associated with extreme weather events and provides ready-to-use predictive tools to identify individuals that are more likely to experience health complications. The indices developed here can also be used to identify regions (neighborhoods) with higher concentration of people at risk, meaning that long-term, climate adaptation programs can be applied not only for individuals but also for geographic regions. Thus, the results from the three studies in this thesis represent a unique perspective in how our public health system could prepare for climate change, avoid negative outcome to vulnerable populations and show new directions for research.