Cohort One: Ghana Randomized Air Pollution and Health Study (GRAPHS)

The GRAPHS study focuses on air pollution caused by cooking with wood or charcoal, which affects around 2.8 billion people worldwide and caused over 2.3 million deaths in 2019 from breathing and heart-related illnesses.

Launched in 2010, GRAPHS randomized controlled trial (RCT) tested whether giving pregnant women cleaner cookstoves could improve their babies’ health by reducing risks like low birth weight and pneumonia. It was the first study of its kind in Africa. While the new stoves did not fully achieve the main goals, the study found that exposure to cooking smoke during pregnancy harms health in many ways. Babies exposed to more smoke were more likely to be born underweight, have poor lung function, get pneumonia, and grow poorly.

The study also showed that children from homes using cleaner liquefied petroleum gas (LPG) stoves had better lung health three years later, and both mothers and children had lower blood pressure. GRAPHS continues to collect important information on environmental exposures and health outcomes, providing a rich source of data and biological samples for future research on how pollution affects long-term health risks.

Cohort Two: Pregnancy Risk Stratification Innovation and Measurement Alliance (PRISMA)

Maternal anemia affects over 600 million women worldwide and increases risks for both mothers and their babies. The World Health Assembly has set a goal to cut anemia in women of reproductive age by half by 2025, but progress has slowed. One problem is that the current methods for measuring and interpreting hemoglobin levels in pregnant women aren’t reliable enough, leading to less effective care and unclear data on the problem’s scale.

To address this, the Bill and Melinda Gates Foundation is funding the PRISMA study, which aims to better understand anemia in pregnancy. The study is currently enrolling 3,000 pregnant women and uses data from one of the largest health research systems in sub-Saharan Africa, known as the Kintampo Health and Demographic Surveillance System (KHDSS).

The team has also received funding Clean Air Fund to study how air pollution impacts maternal and child health. Low-cost air sensors have been installed in communities to measure pollution levels. This allows researchers to explore questions such as:

• a. How does exposure to air pollution during pregnancy affect health outcomes like high blood pressure, preeclampsia, birth weight, and child growth?
• b. Does maternal nutrition influence how air pollution impacts health?
• c. What are the main sources of pollution in these areas?

The results will help improve maternal care and guide public health policies to protect mothers and babies from anemia and the effects of pollution.

Cohort Three: Kintampo Hypertension Program (KHP)

The Kintampo Hypertension Program (KHP) was started in 2015 to address the rising problem of heart diseases (cardiovascular diseases/CVD) and meet community health needs. A survey showed that 24% of adults over 18 years old and about half of adults over 40 had high blood pressure (hypertension). Many of them didn’t know they had it or weren’t receiving proper treatment.

To improve hypertension care, we launched a research study called the Task Strengthening Strategy for Hypertension (TASSH). This program tested a strategy to help community health clinics manage hypertension despite the shortage of doctors in Ghana (only 1 doctor for every 10,000 people). We worked with 70 community clinics and trained health workers with support from mentors and an advisory board to improve care for people with high blood pressure.

• a. Identified how clinics could adopt the strategy and tailored it to suit local needs.
• b. Compared clinics using the new strategy to those providing regular care. Results showed that the new approach helped lower blood pressure.
• c Evaluated what helped or hindered the success of the program, like leadership support and clinic capacity.
• d. Assessed how sustainable the program was after the trial ended.

So far, about 11,000 community members have been screened, creating a large group (cohort) of hypertensive adults, to help study cardiovascular health. This includes blood pressure, glucose levels, and how environmental factors like air pollution affect disease progression.

Cohort Four: Kintampo Health and Demographic Surveillance System (KHDSS)

KHDSS regularly updates its data by visiting households twice a year to record key events like pregnancies, births, deaths, and migrations. Each household is mapped with a unique number and GPS location, and the system collects information on household size, income, and living conditions. This data helps researchers study health issues and environmental factors, such as how air pollution or climate change affects deaths from non-communicable diseases (like heart disease). The information is critical for planning policies to reduce environmental risks and prepare for climate change.

Over the past 10 years, KHDSS has recorded nearly 12,000 deaths and conducted follow-up interviews to determine the causes. The system is a valuable resource for understanding health trends and improving public health in Ghana.

Analyzing Remote Sensing Data for All Cohorts

All KHRC study cohorts and communities are mapped with precise locations over time (longitudinal geocoding). This makes it possible to combine health research data with information from satellites about air pollution (like fine particles in the air, called PM2.5) and climate conditions (like heat and humidity). Our collaborations present opportunities to:

• a. Learn new ways to use satellite data and apply it to study how pollution and climate affect people’s health.
• b. Integrate data into cohorts by linking climate data with community information so that we can track daily climate patterns (like heat levels) from as far back as 1983. This also helps predict future climate changes up to 2050.

Using tools such as machine learning (e.g., XGBoost), researchers can create detailed maps showing daily air pollution levels for small areas (as small as 1 km²) from 2000 onward, using data from NASA and other sources. This approach helps us better understand how air quality and climate changes affect health and provides insights for planning and policymaking.