PROJECT SUMMARY
During the last two decades, nearly half a million people died each year from heat-related causes; climate
change is expected to exacerbate the burden of adverse health outcomes. Heat stress has been associated
with an increase in all-cause mortality, cardiovascular disease and mortality, chronic respiratory disease, lower
respiratory infection, chronic kidney disease, diabetes, adverse pregnancy outcomes, and poor mental health.
In this RO1, we propose to determine personal heat stress of low-income individuals who do not have
access to air conditioning, evaluate the effectiveness, acceptability, feasibility, and scalability of
building-level cooling strategies to reduce indoor heat stress among vulnerable individuals, and
evaluate the impact of these interventions on heart rate. A disproportionate burden of heat-related death
and disease is borne by low-income communities because they do not have access to cooling and suffer from
comorbidities that exacerbate the adverse impacts of heat stress. South Asia faces the greatest current and
predicted loss in disability-adjusted life years due to heat stress, and heat stress is particularly strong in
informal settlements. As such, we plan to conduct this study in informal settlements in Dhaka, Bangladesh. Our
overall hypothesis is that individuals who live in homes with corrugated iron roofs and walls are at elevated risk
of heat stress and that it is possible to modify homes to prevent increases in heart rate associated with heat
stress, ultimately reducing cardiovascular morbidity and mortality. Aim 1 will characterize personal heat stress
in individuals across age ranges, occupations, sex, and housing types, and examine heterogeneity in the effect
of existing building variation on heat stress. Aim 2 will model building-level interventions, test their ability to
cool indoor spaces, and evaluate their impact on heart rate in a randomized-controlled trial. In Phase 1, energy
modeling will be used to evaluate the cooling potential of 12 passive or active building-level infrastructure
modifications, material additions, and technologies to identify six strategies with maximum effectiveness for
households in informal, low-income settlements in Dhaka, Bangladesh. In Phase 2, we will implement each of
the six strategies in 17 homes to experimentally assess their impact on indoor thermal conditions and
determine their feasibility and acceptability. The two most cost-effective interventions will be tested in a
randomized controlled trial in 459 houses in Phase 3. Phase 3 will evaluate the impact of the interventions on
residents’ heart rate (primary outcome), blood pressure, self-reported thermal comfort, wellness, productivity,
fatigue, and indoor thermal conditions (secondary outcomes).
