Cardiovascular challenges of aging in a hotter environment: a narrative review.

The increase in duration, severity, and frequency of extreme heat will have a profound detrimental impact on human health, as extreme heat is the deadliest weather-related event around the world. At the same time, the population of older (>65 yr) adults is rapidly expanding. The exaggerated heat, coupled with an aging population, increases the number of people at risk during environmental extremes. During heat waves, cardiovascular events and complications secondary to elevated core temperatures are the leading cause of increased morbidity and mortality among older adults. Seminal work demonstrates an impaired cardiovascular response to elevated core and skin temperatures in older adults, resulting in an attenuated capacity to lose heat coupled with increased cardiac strain, in support of the epidemiological data. Here, we review the impact of heat stress on the aged cardiovascular system and highlight the question: "In what specific environments does an increased cardiovascular strain begin to occur in older adults?"