Clinical trial NCT06579950: Assessing the Effects of Cool Roofs on Indoor Environments and Health
Official title: The Effects of Cool Roofs on Health, Environmental, and Economic Outcomes: a Global Multi-center Cluster-randomized Controlled Trial
Study type: INTERVENTIONAL
Overall status: RECRUITING
Phase: NA
Conditions: Resting Heart Rate
Blood Glucose Control
Depression
Heat-related Symptoms
Physician Diagnosed Heat-related Illnesses
Food Insecurity
Diet Quality
Health-related Quality of Life
Indoor Thermal Comfort
Coping Ability
Life Satisfaction
Healthcare Provider Utilization
Hospitalization
Systolic Blood Pressure
Diastolic Blood Pressure
Inner Ear Canal Temperature
Dehydration
Sleep Quality
Cognition
Productivity
Aggression
Indoor Air Temperature
Indoor Relative Humidity
Indoor Heat Index
Household Energy Expenditure
Keywords: Hot Temperature
Humidity
Housing
Heart rate
Cardiovascular
Depression
Mental health
Blood glucose
Diabetes
Cool roof
Heat Stress
Lead sponsor: University of Auckland, New Zealand
Sponsor class: OTHER
Collaborators: name: Sika Services AG
name: SOPREMA
name: Engineered Polymer Solutions (EPS B.V.)
name: Resene
name: Pacific Community
name: Habitat for Humanity
name: The Tindall Foundation
name: Rutgers University
name: Boston University
name: London School of Hygiene and Tropical Medicine
name: Heidelberg University
name: Instituto Tecnológico de Hermosillo
name: University of Ouagadougou, Burkina Faso
name: Indian Institute of Public Health, India
First posted: 2024-08-30
Enrollment: 3200
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 Asian, Latin American, African, and Pacific climate hotspots have broken record highs in 2024, driven by man-made climate change. Solutions are needed to reduce heat exposure in communities. Sunlight-reflecting cool roof coatings passively reduce indoor temperatures and energy use to protect home occupants from extreme heat. Occupants living in poor housing conditions globally - for example in informal settlements, slums, and low-socioeconomic households - are especially vulnerable to increased indoor heat exposure.

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

The long-term research goal is to identify viable passive housing adaptation technologies with proven health and environmental benefits to reduce the burden of heat stress in communities affected by heat globally. To meet this goal, the investigators will conduct a cluster-randomized controlled trial to establish the effects of cool roof use on health, indoor environment and economic outcomes in four urban climate hotspots: Ouagadougou, Burkina Faso; Hermosillo, Mexico; Ahmedabad, India; and Niue, Oceania.

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 our homes, are ideal for deploying interventions to reduce heat exposure and accelerate adaptation efforts. However, currently there 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.

Sunlight-reflecting cool roof coatings passively reduce indoor temperatures and lower energy use, offering protection to home occupants from extreme heat. The investigators aim to conduct a global multi-centre cluster-randomized controlled trial investigating the effects of cool-roof use on health, environmental and economic outcomes in four urban climate hotspots - Ouagadougou, Burkina Faso (sub-Saharan Africa), Ahmedabad, India (Asia), Niue (Oceania), and Hermosillo, Mexico (Latin America). The sites represent hotspots where people experience a triple burden from heat exposure, chronic health issues and vulnerable housing conditions (slums, informal settlements and low socioeconomic housing). They also exhibit diversity in climate profiles, housing typology, level of socioeconomic development, population density and rates of urbanisation.

The trial will quantify whether cool roofs are an effective passive home cooling intervention with beneficial health effects for vulnerable populations in four locations. Findings will inform 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.

Primary outcomes:
measure: Resting heart rate
timeFrame: Eight measurements will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.
measure: Blood glucose control
timeFrame: Two measurements will be taken: one at baseline and one in the last month of three consecutive hottest months.
measure: Depression
timeFrame: Eight measurements will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.
Secondary outcomes:
measure: Heat-related symptoms
timeFrame: Eight measurements will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.
measure: Physician diagnosed heat-related illnesses
timeFrame: Eight measurements will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.
measure: Food insecurity
timeFrame: Eight measurements will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.
measure: Diet quality
timeFrame: Eight measurements will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.
measure: Health-related quality of life
timeFrame: Eight measurements will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.
measure: Indoor thermal comfort
timeFrame: Eight measurements will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.
measure: Coping ability
timeFrame: Eight measurements will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.
measure: Life satisfaction
timeFrame: Eight measurements will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.
measure: Healthcare provider utilization
timeFrame: Eight measurements will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.
measure: Hospitalization
timeFrame: Eight measurements will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.
measure: Systolic Blood Pressure
timeFrame: Eight measurements will be taken: one at baseline and seven over 12 months, covering the three consecutive hottest months and four alternate months.
measure: Diastolic Blood Pressure
timeFrame: Eight measurements will be taken: one at baseline and seven over 12 months, covering the three consecutive hottest months and four alternate months.
measure: Cognition
timeFrame: Eight measurements: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.
measure: Inner Ear Canal Temperature
timeFrame: Eight measurements will be taken: one at baseline and seven over 12 months, covering the three consecutive hottest months and four alternate months.
measure: Dehydration
timeFrame: Eight measurements will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.
measure: Sleep quality
timeFrame: Eight measurements: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.
measure: Aggression
timeFrame: Eight measurements: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.
measure: Productivity
timeFrame: Eight measurements will be taken: one at baseline and seven over 12 months, covering the three consecutive hottest months and four alternate months.
measure: Indoor air temperature
timeFrame: Measurements at 15 minute intervals for 12 months.
measure: Indoor relative humidity
timeFrame: Measurements at 15 minute intervals for 12 months.
measure: Indoor heat index
timeFrame: Measurements at 15 minute intervals for 12 months.
measure: Household energy expenditure
timeFrame: Eight measurements will be taken: one at baseline and seven over 12 months, covering the three consecutive hottest months and four alternate months.
Other outcomes:
Locations:
city: Ouagadougou
country: Burkina Faso
facility: University Joseph Ki-Zerbo
city: Ahmedabad
country: India
facility: Indian Institute of Public Health Gandhinagar
state: Gandhinagar
city: Hermosillo
country: Mexico
facility: Instituto Tecnológico de Hermosillo
state: Sanora
city: Alofi
country: Niue
facility: Niue
Study officials:
affiliation: University of Auckland, New Zealand
name: Collin Tukuitonga, Sir. Dr.
role: PRINCIPAL_INVESTIGATOR
References: