Clinical trial NCT06831006: Assessing the Effect of Cool Roofs on Health Using Smartwatches in Hermosillo, Mexico
Official title: A Randomized Controlled Trial (RCT) Evaluating the Effects of Cool Roofs on Health Outcomes Using Smartwatches in Hermosillo, Mexico
Study type: INTERVENTIONAL
Overall status: NOT_YET_RECRUITING
Phase: NA
Conditions: Heart Rate
All-day Steps
Distance Walked
Active Minutes
Moderate-intensity Activity Minutes
Vigorous-intensity Activity Duration
Sleep Quantity
Time in Sleep Stages
Awake Duration
Sleep Score
Keywords: Hot Temperature
Humidity
Housing
Wearable
Smartwatch
Heart rate
Cardiovascular
Physical activity
Sleep
Cool roof
Heat stress
Lead sponsor: University of Auckland, New Zealand
Sponsor class: OTHER
Collaborators: name: Heidelberg University
name: London School of Hygiene and Tropical Medicine
name: Rutgers University
name: Instituto Tecnológico de Hermosillo
name: Labfront
name: Wellcome Trust
name: Hermosillo City Government
name: EPS
First posted: 2025-02-17
Enrollment: 800
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: PREVENTION

Brief summary: Ambient air temperatures in Mexico have broken record highs in 2024 with Hermosillo reaching the highest maximum temperature recorded in Mexico at 51.9 C. Solutions are needed to build heat resilience in communities and adapt to increasing heat from climate change. Sunlight-reflecting cool roof coatings may passively reduce indoor temperatures and energy use to protect home occupants from extreme heat. Occupants living in poor housing conditions in the northern zone of Mexico are susceptible to increased heat exposure.

Heat exposure can instigate and worsen numerous physical, mental and social health conditions. The worst adverse health effects are experienced in communities that are least able to adapt to heat exposure. By reducing indoor temperatures, cool roof use may promote heart health, sleep and physical activity in household occupants.

The long-term research goal of the investigators is to identify viable passive housing adaptation technologies with proven health benefits to reduce the burden of heat stress in communities affected by heat in northern zone of Mexico. To meet this goal, the investigators will conduct a randomized controlled trial to establish the effects of cool roof use on heart rate, sleep and physical activity in Hermosillo, Mexico.

Detailed description: Increasing heat exposure from climate change is causing and exacerbating heat-related illnesses in millions worldwide - particularly in low-resource settings. June 2024 was the 13th consecutive hottest month on record globally - shattering previous records. Heat exposure can instigate and worsen health conditions, including cardiovascular, metabolic, endocrine and respiratory disease, heat-related illnesses, pregnancy complications, and mental health conditions. Adaptation is essential for protecting people from increasing heat exposure. The built environment, especially homes, is ideal for deploying interventions to reduce heat exposure and accelerate adaptation efforts. However, there currently is a lack of evidence on a global scale - generated through empirical studies - guiding the uptake of interventions to reduce heat stress in low-resource settings.

Cities and towns of LMIC are among the most vulnerable to the adverse impacts of climate change and are likely to experience increases in ambient air temperature over the coming decades. People in Hermosillo (located in the State of Sonora, Mexico) are exposed to heat and low humidity year-round. The State of Sonora has a large burden of non-communicable diseases (NCDs), with nearly 28% of deaths due to NCDs, such as heart diseases and diabetes mellitus. The combined burden of heat and NCDs places Sonora's, especially Hermosillo's, populations at greater risk of adverse health effects from heat extremes.

Sunlight-reflecting cool roof coatings passively reduce indoor temperatures and lower energy use, offering protection to home occupants from extreme heat. The investigators therefore aim to conduct a randomized controlled trial investigating the effects of cool roofs on heart rate, sleep and physical activity using smartwatches in Hermosillo.

The trial will quantify whether cool roofs are an effective passive home cooling intervention with beneficial health effects for vulnerable populations in Hermosillo. Findings will inform regional and global policy responses on scaling cool roof implementation to protect people from increasing heat exposure driven by climate change.

Eligibility criteria: Inclusion Criteria:

* Permanent household resident

Exclusion Criteria:

* Roof damage, inaccessible or instability of roof adversely affecting cool roof coating application.
* Participant unable to provide written/verbal informed consent. Participants will be excluded if they are not willing or able to wear a smartwatch.
* Participants will be excluded if they do not have a smartphone with an internet connection that can connect to the smartwatch.
* Only one participant per household.

Primary outcomes:
measure: Heart rate
timeFrame: Smartwatches will be worn for two consecutive weeks per month. Eight measurement points will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.
Secondary outcomes:
measure: All-day steps
timeFrame: Smartwatches will be worn for two consecutive weeks per month. Eight measurement points will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.
measure: Active minutes
timeFrame: Smartwatches will be worn for two consecutive weeks per month. Eight measurement points will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.
measure: Distance walked
timeFrame: Smartwatches will be worn for two consecutive weeks per month. Eight measurement points will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.
measure: Moderate-intensity activity minutes
timeFrame: Smartwatches will be worn for two consecutive weeks per month. Eight measurement points will be taken: one at barements will be taken continuously for 12 months. Participants will be asked to wear their smartwatch for at least two weeks every month.
measure: Vigorous-intensity activity duration
timeFrame: Smartwatches will be worn for two consecutive weeks per month. Eight measurement points will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.
measure: Sleep quantity
timeFrame: Smartwatches will be worn for two consecutive weeks per month. Eight measurement points will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.
measure: Time in sleep stages
timeFrame: Smartwatches will be worn for two consecutive weeks per month. Eight measurement points will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.
measure: Awake duration
timeFrame: Smartwatches will be worn for two consecutive weeks per month. Eight measurement points will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.
measure: Sleep score
timeFrame: Smartwatches will be worn for two consecutive weeks per month. Eight measurement points will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.
Other outcomes:
Locations:
city: Hermosillo
country: Mexico
facility: Instituto Tecnológico de Hermosillo
Study officials:
affiliation: University of Auckland, New Zealand
name: Collin Tukuitonga, Sir. Dr.
role: PRINCIPAL_INVESTIGATOR
References: