Heat waves and the elderly: reducing thermal and cardiovascular consequences

摘要 热浪是致命的，导致老年人死亡的人数与其他任何年龄的人都不成比例 组重要的是要注意，这种死亡主要是心血管疾病，而不是体温过高本身。 尽管如此，我们对实际高温下老化对心血管功能的影响知之甚少。 波浪状的条件。这项工作的中心假设是，老年人表现出更大的心血管疾病， 在热浪条件下的压力，这可以通过采用低能耗冷却来缓解 战略布局目的1将检验这一假设，即老年人的体温调节能力受损 在长时间暴露于热浪条件下会导致心血管压力升高。 将评估老年人相对于年轻人的综合心血管和热反应 在暴露于两种延长的热浪条件下：热和潮湿（复制1995年芝加哥热浪）， 非常炎热和干燥（复制2018年的洛杉矶热浪）。目标2将检验皮肤润湿是 一种有效的降温方式，可减轻核心体温升高和伴随的心血管疾病 压力在热浪中的老年人，而使用风扇可能是有害的，这取决于空气温度 以及是否使用皮肤润湿。尽管空调是最有效的防热措施- 相关的发病率和死亡率，1/8（~12%）的美国人没有空调，这 在美国中西部和东北部， 浪特别高。此外，社会经济地位、停电、政府- 实施轮流停电，以及与COVID-19相关的公共场所关闭（例如，商场图书馆老年中心 等等）。在最需要空调的时候，威胁到整个区域的空调使用。因此有 必须确定非空调依赖的方式，以减轻核心的过度海拔 热浪条件下老年人的体温和相关的心血管应激。这一目标将 评估仅皮肤润湿、仅使用风扇以及皮肤润湿和风扇组合使用在减轻 在这两种情况下，老年人的核心体温和相关的心血管应激过度升高， 目标1中概述的热浪类型。这项工作的预期成果将重新塑造我们的 了解热浪期间衰老对心血管功能的影响，以及确定 低能耗冷却方式在拯救这一弱势群体的生命方面的功效， 热浪暴露。

Abstract Heat waves are lethal and cause a disproportionate number of deaths in the elderly relative to any other age group. It is important to note that such deaths are primarily cardiovascular, not hyperthermia itself, in origin. Nevertheless, we know relatively little about the effects of aging on cardiovascular function during actual heat wave-like conditions. The central hypothesis of this work is that the elderly exhibit greater cardiovascular stress during heat wave conditions, which can be mitigated by employing low-energy demand cooling strategies. Aim 1 will test the hypothesis that recognized impairments in thermoregulatory capacity in the elderly will culminate in heightened cardiovascular stress during prolonged exposure to heat wave conditions. Comprehensive cardiovascular and thermal responses in the elderly, relative to younger adults, will be evaluated during exposure to two prolonged heat wave conditions: hot and humid (replicating the 1995 Chicago heat wave), very hot and dry (replicating the 2018 Los Angeles heat wave). Aim 2 will test the hypothesis that skin wetting is an effective cooling modality to attenuate elevations in core body temperature and accompanying cardiovascular stress during heat waves in the elderly, while the use of a fan may be detrimental depending on air temperature and whether skin wetting is employed. Though air conditioning is the most effective strategy to prevent heat- related morbidity and mortality, 1 in 8 (~12%) Americans do not have access to air conditioners, and this percentage is likely higher in the Midwest and Northeast United States where injury and deaths during heat waves are particularly high. Moreover, factors such as socio-economic status, power outages, government- imposed rolling blackouts, and COVID-19 related closures of public spaces (e.g., malls, libraries, senior centers, etc.) threaten region-wide access to air conditioning often at times when it is most needed. Therefore, it is essential to identify non-air conditioning dependent modalities that will attenuate excessive elevations in core body temperature and associated cardiovascular stress in the elderly during heat wave conditions. This aim will assess the efficacy of skin wetting only, fan use only, and a combination of skin wetting and fan use in mitigating excessive elevations in core body temperature and associated cardiovascular stress in the elderly during both types of heat waves outlined in Aim 1. The expected outcomes from this body of work will re-shape our understanding of the consequences of aging on cardiovascular function during heat waves, as well as identify the efficacy of low-energy cooling modalities directed towards saving the lives of this vulnerable population during heat wave exposure.