What a Global Research Study Taught Us About Clean Indoor Air and Your Health.

As much as cigarettes and smog impact lung health, the air quality inside our homes can make a big difference, too. Global clinical trials like the HAPIN trial allow researchers at MedStar Health to uncover key insights about indoor air pollution that improve diagnosis and treatment for patients here at home.

Several years ago, while traveling in rural areas of Nepal and visiting family in Eastern Europe, I was warmly welcomed into local homes. When I stepped inside, I found that most families cooked their meals over open, indoor fires. 

The rooms were filled with thick, heavy smoke. As I struggled to see through the haze, I witnessed how deeply everyday living conditions can shape our lung health.

While this isn’t common in the U.S. compared to other parts of the world, MedStar Health patients come from all over the country and the world. Many grew up or worked in places where indoor pollutants are part of daily life.  

Across the world, more than 1 in 3 people (about 3 billion humans) cook or heat their homes using open fires or traditional stoves. Exposure to household air pollution is behind an estimated 2.3 million premature deaths per year.

To better understand these hidden exposures, MedStar Health Research Institute collaborated on the global Household Air Pollution Intervention Network (HAPIN) trial. This study examined how indoor air quality can impact human health, providing insights that help us diagnose and care for people in communities close to home.

How does indoor air pollution affect the body?

In many low- and middle-income regions across the world, families rely on solid fuels for daily cooking and heating including:

• Wood, brush, and crop waste

• Animal dung 

• Charcoal and raw coal

Burning these materials indoors without proper ventilation can fill the air with smoke and soot. The smoke contains microscopic particles that can be breathed deep into the lungs and pass into the bloodstream.

If you inhale this smoke often, it can create long-term health risks such as:

• Lung damage: Regular smoke exposure can lead to chronic obstructive pulmonary disease (COPD), a lung condition that makes it hard to breathe. It can also lead to severe airway swelling and an increased risk of lung cancer and throat cancer.

• Heart and circulation issues: Fine particles trigger inflammation in the whole body, which can raise blood pressure, damage blood vessels, and increase the risk of a stroke.

• Risks for mothers and babies: Breathing indoor smoke during pregnancy can make it harder for blood to flow through the placenta. This can increase the risk of low birth weight, delayed growth, and severe childhood pneumonia.

The HAPIN trial: What we learned from families around the world.

Supported by $35 million from the National Institutes of Health and the Gates Foundation, the global HAPIN trial brought together experts from MedStar Health Research Institute and other leading research organizations.

Researchers followed more than 3,000 households for about 18 months in Guatemala, India, Peru, and Rwanda that included pregnant women, infants, and older women. Half of the households received clean-burning liquefied petroleum gas (LPG) stoves and a reliable fuel supply, while the others continued using traditional cooking methods during the study. (After the study was completed, participants in this control group also received clean-burning stoves.)

We found that the cleaner-burning stoves were very successful at clearing the air. They reduced indoor air pollution by about 72%. Families also experienced health benefits. For example, pregnant women had healthier oxygen levels in their blood, which can support both maternal and infant health.

Our findings showed that reducing indoor smoke is important, but it may not be enough on its own to quickly improve conditions such as pneumonia or low birth weight. Many factors affect a child's health. As we continue to follow our participants through childhood in the next phase of this trial, we hope to understand how household air pollution influences growth, development, and long-term health.

What this research means for healthcare at home.

One of the lessons I've learned as a pulmonologist is that understanding a person's environment can be just as important as understanding their medical history. I've cared for patients whose lung health was shaped by environmental exposures that occurred years or even decades earlier.

Your environment matters, and exposures from years ago may still affect your health today.

Studies like HAPIN help us answer fundamental questions about health and wellbeing. What we learn from families around the world can help us provide more personalized care and ask better questions when patients come to our clinics with breathing problems. This is especially important in the Maryland, Washington, D.C., and Northern Virginia area, where we’re treating families who originated from all over the world. 

Lung damage can differ depending upon the source.

Household air pollution from cooking fires can affect the lungs differently than smoking tobacco. The changes on lung scans can appear different depending on sources, and the symptoms vary depending on source of smoke exposure. Knowing about that exposure can help doctors better understand symptoms and provide the right care.

Learning about air quality in everyday life.

Air pollution affects everyone, no matter where they live.  The more we learn about how air pollution from sources like indoor fires, mold, traffic, and gas emissions affects the lungs, the better we can prevent, diagnose, and treat related health problems.

Related: Read “New Research: Mobile Pediatric Asthma Screening Tool Connects More Kids with Respiratory Care.”

Take charge of your home’s air quality.

Follow these practical steps for cleaner air at home:

• Ventilate while cooking: Always turn on your range hood exhaust fan or open nearby windows when using the stove. Keep your children out of the kitchen while you’re cooking.

• Filter indoor air: A portable air purifier with HEPA filters can capture particles and reduce asthma triggers. Vacuum regularly to manage dust.

• Protect your lungs: Stay indoors or wear a well-fitted mask on poor air quality days. Don’t smoke or use tobacco products, especially indoors. Stay up to date on vaccines such as the flu shot and wash your hands often to prevent the spread of respiratory infections.

Partnering for lifelong lung health.

Everyone’s health story is unique, and we’re collaborating with leading researchers to learn more about how to provide the most advanced respiratory care.

If you grew up or lived in an environment with exposure to smoke, let your doctor know during your next visit. Sharing that information helps us tailor your lung care and helps you breath better at every stage of life.