Recruiting

Air Conditioning

Sponsor:

Harvard School of Public Health (HSPH)

Code:

NCT06982339

Conditions

Hot Weather; Adverse Effect

Heat Effect

Heat Stress

Heat Stroke, Heat Exhaustion

Heat Exposure

Eligibility Criteria

Sex: All

Age: 55 - 70+

Healthy Volunteers: Not accepted

Interventions

Air Conditioner

Electricity subsidy

Study Details

Brief summary:

The goal of this stepped wedge trial is to assess the practical effects of air conditioners on hot weather impacts among older adults. The main questions it aims to answer are:

How does the presence of an air conditioning unit affect heat stress, heat strain, mental health, and healthcare utilization among older adults who did not previously have access to air conditioning?

How, and in what conditioners, do older adults use air conditioning once it is installed in their home?

Researchers will compare participants in arms with (A) and without (B) air conditioning units in the first summer season; this will allow them to assess the effect of air conditioners. In the second summer season, both arms will have air conditioning units, but those in the year two distribution arm (B) will receive an electricity subsidy, while those in the year one AC distribution arm (A) will not, allowing researchers to assess the effect of an electricity subsidy.

Participants will be randomized to receive an air conditioner and financial support for electricity costs in either the first summer season or the second summer season of the study.

  • Heat stress, heat strain, mental health, and healthcare utilization will be assessed via participant survey.
  • Air conditioner utilization will be assessed via continuous load monitoring devices.
  • Indoor air temperature will be assessed via continuous data loggers.

Conditions

Hot Weather; Adverse Effect

Heat Effect

Heat Stress

Heat Stroke, Heat Exhaustion

Heat Exposure

Study ID

NCT06982339

Start date

May 19, 2025

Status verified date

Aug, 2025

Completion date

Oct 15, 2026

Anticipated

Primary completion date

Oct 15, 2026

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 55 - 70+

Healthy Volunteers: Not accepted

Inclusion Criteria:

  • reside in Roxbury, Dorchester, East Boston or Mattapan MA
  • age 55-95 years old
  • speak English or Spanish
  • do not have air conditioning in the home
  • living with at least one of the following conditions: chronic CVD (hypertension, hyperlipidemia, diabetes, history of stroke or myocardial infarction, atrial fibrillation, or heart failure), chronic pulmonary disease (asthma, COPD/emphysema, interstitial lung disease), chronic neurologic disease (stroke, Parkinson's disease, or other chronic neurologic conditions), chronic mental health conditions (including anxiety disorder, major depression, bipolar disorder), and/or history of hospitalization (defined as spending at least one night in the hospital) for any reason within the past three years.

Exclusion Criteria:

\- Lack a location in their home suitable for installation of the AC unit provided during the research study.

Study Design

Enrollment

100 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Prevention

Interventions and Outcome Measures

Arms

experimental: Early Air Conditioning

Year 1: Participants receive a window AC unit and a financial subsidy for electricity.

Year 2: Participants continue to have their AC unit, but do not receive a financial subsidy for electricity.

no intervention: Delayed Air Conditioning

Year 1: No intervention. Year 2: Participants receive an AC unit along with a financial subsidy for electricity.

Interventions

Air Conditioner

Air conditioners will be window-mounted units powered by 110v AC.

Electricity subsidy

Electricity subsidies will consist of a single block subsidy of USD 100, intended to provide support for the electricity costs associated with operating an air conditioning unit.

Primary outcome measure

  • Environmental Symptoms Questionnaire (ESQ-IV) [ Time Frame: Difference in self-reported symptoms on HSSQ administered in the late summer season, 2-12 weeks after enrollment. ]

Central Contacts and Locations

Central contacts

Caleb Dresser Assistant Professor in Environmental Health, MD MPH

(617) 446-3248beattheheatboston@gmail.com

Locations

Harvard TH Chan School of Public Health

Recruiting

Boston, Massachusetts, United States, 02215

Contacts

Caleb J Dresser, MD MPH

6174950000cdresser@hsph.harvard.edu

More Information

Sponsor

Harvard School of Public Health (HSPH)

Last update posted

Jan 22, 2026

Last verified

Aug, 2025

Keywords

  • Cooling
  • Air conditioner
  • Heat related illness
  • stepped wedge

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by Harvard School of Public Health (HSPH) on 2026-01-22.