Identifying the importance of age, sex, ethnicity and obesity in establishing cardiovascular-respiratory reflex responses to heat exposure

One of the major threats to human health is climate change and its association with increased exposure to extreme heat. An important effect is an increase in the frequency, duration and intensity of heatwave exposure. People now experience more than double the number of heatwave days compared with 1986-2005, and this will increase in the foreseeable future. Heatwave exposure can have a detrimental effect on health and in the worse cases can cause sudden death. Therefore, there is an urgent need to identify those people who may be more vulnerable to heat exposure to provide protection.
Exposure to heat puts a major stress on the cardiovascular and respiratory systems. Key reflex activation includes an increase in breathing, a rise in heart rate, an increase in cardiac output and blood flow redistribution. This is needed to maintain blood pressure and adequate O2 delivery to the brain. Despite its importance very little is known about variations in cardiovascular-respiratory reflex responses to heat exposure in different people. Therefore, the current project will monitor, in humans, cardiovascular-respiratory reflexes to heat exposure in a variety of different groups. This will enable us to identify the importance of age, sex, ethnicity and obesity in establishing vulnerability to heat exposure. We will also monitor the impact of heat exposure on the ability to exercise and respond to other stimuli including low oxygen (as experienced at altitude) and high carbon dioxide (as experienced in chronic lung disease). Furthermore, we will probe the importance of carotid body function in driving the cardiovascular-respiratory response to heat exposure and the extent of disruption of ventilation-metabolism matching in the different groups.
Training will be provided to measure human cardiovascular-respiratory function such as ECG, minute ventilation (spirometry), arterial blood pressure, O2 saturation, blood gases, as well as performing biomarker analysis.
Applicants should have a strong background in one of the following: biomedical sciences, human physiology, cardiovascular physiology or respiratory physiology. They should have a commitment to biomedical science or physiology research and hold, or realistically expect to obtain, at least an Upper Second-Class Honors Degree in biomedical sciences or a physiology related subject.


How to apply
Informal enquiries should be directed to Dr Andrew Holmes ([email protected]), Dr Joesph Welch ([email protected]) or Dr Andrew Coney ([email protected]), who will form the supervisory team.

To be considered for this studentship, please send the following documents to Dr Andrew Holmes ([email protected])

• A detailed CV, including your nationality and country of birth;

• Names and addresses of two referees;

• A covering letter highlighting your research experience/capabilities;

• Copies of your degree certificates with transcripts;

• Evidence of your proficiency in the English language, if applicable.

References:

Romanello, M., et al., The 2023 report of the Lancet Countdown on health and climate change: the imperative for a health-centred response in a world facing irreversible harms. Lancet, 2023. 402(10419): p. 2346-2394.

Crandall, C.G. and T.E. Wilson, Human Cardiovascular Responses to Passive Heat Stress, Comprehensive Physiology. 2015. p. 17-43.

Gibbons, T.D., et al., Contribution of the carotid body to thermally mediated hyperventilation in humans. J Physiol, 2022. 600(15): p. 3603-3624.

Liu, J., et al., Heat exposure and cardiovascular health outcomes: a systematic review and meta-analysis. Lancet Planet Health, 2022. 6(6): p. e484-e495.