CompletedNot Applicable

Establishing Evidence-based Indoor Temperature Thresholds to Protect Health

Canada16 participantsStarted 2019-06-01

Plain-language summary

An individual's ability to adequately cope with short- or long-term increases in ambient temperature is critical for maintaining health and wellbeing. Prolonged increases in temperature (heatwaves) pose a serious health risk for older adults, who have a reduced capacity to regulate body temperature. Currently, however, there is a lack of information regarding how different environmental conditions experienced during heatwaves impact body temperature regulation and physiological function. This is particularly important in the context of ambient conditions in the home, where older adults spend the majority of their time. This project will address this important issue by exposing healthy older adults to prolonged (8-hour) simulated heatwaves comprising a range of environmental conditions representative of an actively cooled domicile through to a worst-case scenario (i.e., no capacity for home cooling). The investigators will directly measure their ability to regulate their body temperature and the associated impact on the autonomic control of the heart. The investigators anticipate that physiological strain will be mild during prolonged exposure to conditions below the currently recommended thresholds set by Toronto Public Health (26°C). However, at higher indoor temperatures, impairments in body temperature and cardiovascular regulation will be seen.

Who can participate

Age range65 Years – 80 Years

SexALL

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AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

Inclusion Criteria: * Male or female (non-pregnant) adults aged 18-80 with or without a) chronic hypertension (elevated resting blood pressure; as defined by Heart and Stroke Canada and Hypertension Canada), b) type 2 diabetes as defined by Diabetes Canada, with at least 5 years having elapsed since time of diagnosis and or c) obesity as defined by the World Health Organization (Body Mass Index \[BMI\] greater than or equal to 30) * non-smoking. Exclusion Criteria: \- Episode(s) of severe hypoglycemia (requiring the assistance of another person) within the previous year, or inability to sense hypoglycemia (hypoglycemia unawareness). Serious complications related to your diabetes (gastroparesis, renal disease, uncontrolled hypertension, severe autonomic neuropathy). * Uncontrolled hypertension - BP \>150 mmHg systolic or \>95 mmHg diastolic in a sitting position. * Restrictions in physical activity due to disease (e.g. intermittent claudication, renal impairment, active proliferative retinopathy, unstable cardiac or pulmonary disease, disabling stroke, severe arthritis, etc.). * Use of or changes in medication judged by the patient or investigators to make participation in this study inadvisable. * Cardiac abnormalities identified in your physical health screening form (adults \<65 years of age and older; adults \<60 years of age and older with diabetes and or hypertension) or during exercise stress testing as assessed by 12-lead (all adults ≥65 years of age and older).

What they're measuring

Rectal temperature

Timeframe: Final 15 min of exposures

Mean skin temperature

Timeframe: Final 15 min of exposures

Trial details

NCT IDNCT04348630

SponsorUniversity of Ottawa

Sponsor typeOTHER

Study typeINTERVENTIONAL

Primary completion2021-11-11