Project 461200

An important consequence of global warming is more frequent and intense periods of extreme heat events. Over the past 20 years, extreme heat has killed more people worldwide than all other natural disasters combined. During periods of extreme heat, people with heart disease are more likely to die or be hospitalized. However, the reasons why people with heart disease are more vulnerable to the effects of extreme heat are unknown. The general objective of this project is to study reasons that may explain the vulnerability to extreme heat of people with heart disease. We will study 3 potential reasons. First, we will measure the amount of blood that irrigates the heart during heat exposure in healthy young adults to determine the "normal" response. We will also perform this measure in healthy older adults and older adults with heart disease to determine how age and heart disease affect blood supply to the heart during heat exposure. Second, we will determine if extreme heat exposure results in the heart not getting enough oxygen to support the wok it is performing. Third, we will explore the possibility that extreme heat exposure increases markers of inflammation and blood thickening in healthy older adults and older adults with heart disease. Taken together, the research that will performed as part of this project will help us better understand why people with heart disease are more vulnerable to the health effects of extreme heat. The results may help public health efforts to minimize the negative health impacts of extreme heat on vulnerable individuals.