Assessing the Effects of Cool Roofs on Indoor Environments and Health: a Global Multi-center Study
NCT Number: NCT06579950
Acronym: REFLECT
Status: NOT_YET_RECRUITING
Study Type: INTERVENTIONAL
Phases: 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
Sponsor: Aditi Bunker
Sex: ALL
Age: ADULT, OLDER_ADULT
Enrollment: 3200
Study Design: Allocation: RANDOMIZED|Intervention Model: PARALLEL|Masking: DOUBLE (INVESTIGATOR, OUTCOMES_ASSESSOR)|Primary Purpose: PREVENTION
Start Date: 2024-09-02
Completion Date: 2026-01-31

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.

Primary Outcome Measures: Resting heart rate, Resting heart rate in beats per minute measured as the average of three readings in the left arm over one hour using Blip portable automated sphygmomanometers., Eight measurements will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.|Blood glucose control, Three month average of blood glucose in mmol/mol measured as glycosylated hemoglobin (HbA1c) using capillary blood and the HemoCue® HbA1c 501 System., Two measurements will be taken: one at baseline and one in the last month of three consecutive hottest months.|Depression, Self-reported presence and frequency of symptoms of depression assessed using aggregate score of the Patient Health Questionnaire 9 (PHQ-9)., Eight measurements will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.
Secondary Outcome Measures: Heat-related symptoms, Self-reported heat-related symptoms in the past month, assessed using a recall questionnaire., Eight measurements will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.|Physician diagnosed heat-related illnesses, Self-reported new diagnosis from a medical practitioner of a heat-related illness in the last month assessed using a recall questionnaire., Eight measurements will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.|Food insecurity, Self-reported experience based measure of individual food security assessed using the Food Insecurity Experience Scale (FIES)., Eight measurements will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.|Diet quality, Self-reported individual food group consumption in the previous 24 hours assessed using the Diet Quality Questionnaire (DQQ)., Eight measurements will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.|Health-related quality of life, Current self-reported health-related quality of life assessed using the EuroQol EQ-5D-5L quality assessment tool., Eight measurements will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.|Indoor thermal comfort, Self-reported household heat, humidity and comfort experience over the last four weeks assessed using a recall questionnaire., Eight measurements will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.|Coping ability, Self-reported coping strategies for high indoor temperatures assessed using a recall questionnaire., Eight measurements will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.|Life satisfaction, Current self-reported life satisfaction assessed using the World Values Survey., Eight measurements will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.|Healthcare provider utilization, Self-reported healthcare provider utilization in the past four weeks assessed using a recall questionnaire., Eight measurements will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.|Hospitalization, Self-reported overnight hospital stay in the past four weeks assessed using a recall questionnaire., Eight measurements will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.|Systolic Blood Pressure, Maximum blood pressure (mmHg) during systole measured as the average of three readings in the left arm over one hour using Blip portable automated sphygmomanometers., Eight measurements will be taken: one at baseline and seven over 12 months, covering the three consecutive hottest months and four alternate months.|Diastolic Blood Pressure, Minimum blood pressure (mmHg) during diastole measured as the average of three readings in the left arm over one hour using Blip portable automated sphygmomanometers., Eight measurements will be taken: one at baseline and seven over 12 months, covering the three consecutive hottest months and four alternate months.|Cognition, Accuracy and response time to the four-choice Deary-Liewald Test measured using the CogniFit app-based assessment tool., Eight measurements: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.|Inner Ear Canal Temperature, Internal body temperature (℃) measured once using Braun digital ear thermometer., Eight measurements will be taken: one at baseline and seven over 12 months, covering the three consecutive hottest months and four alternate months.|Dehydration, Dehydration as indicated by urine specific gravity ≥1.020 measured as urine specific gravity using Siemens Multistix SG dipstick., Eight measurements will be taken: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.|Sleep quality, Self-reported sleep distrubance assessed using the Athens Insomnia Scale (AIS)., Eight measurements: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.|Aggression, Self-reported personal aggresion assessed using the Buss-Perry Aggression Questionnaire-Ultra Short Form (BPAQ-ML)., Eight measurements: one at baseline and seven over 12 months, covering three consecutive hottest months and four alternate months.|Productivity, Self-reported job absenteeism and presenteeism assessed using the Health and Work Performance Questionnaire Short Form (HPQ-SF)., Eight measurements will be taken: one at baseline and seven over 12 months, covering the three consecutive hottest months and four alternate months.|Indoor air temperature, Indoor air temperature (℃) measured using Hobo MX1101 heat and humidity measurement device., Measurements at 15 minute intervals for 12 months.|Indoor relative humidity, Ratio of the amount of water vapor present in the air to the greatest amount possible at the same temperature (%) measured using Hobo MX1101 heat and humidity measurement device., Measurements at 15 minute intervals for 12 months.|Indoor heat index, Index that combines air temperature and relative humidity (℃) based on temperature and humidity measurements from the Hobo MX1101 heat and humidity measurement device calculated using the formulae endorsed by the US National Oceanic and Atmospheric Administration., Measurements at 15 minute intervals for 12 months.|Household energy expenditure, Self-reported household energy expenditure assessed using a recall questionnaire from the head of the household., Eight measurements will be taken: one at baseline and seven over 12 months, covering the three consecutive hottest months and four alternate months.