More green spaces not only boost air quality but also reduce heart disease deaths, according to a new study presented at the American Heart Association’s Scientific Sessions 2020. 

Greenness is a measure of vegetative presence, such as shrubs, grass, and trees that is often assessed by NASA imaging of Earth and via other methods. 

The study authors used the Normalized Difference Vegetative Index (NDVI), which measures wavelengths of visible and near-infrared sunlight reflected from the Earth’s surface via NASA satellite imagery. A higher index score means more healthy vegetation, with NDVI values ranging from 0.00-0.80. Investigators compared a region’s NDVI score to national disease death rates from the CDC and the Prevention’s Interactive Atlas of Heart Disease. 

For every 0.10 unit increase in greenness, death from heart disease decreased by 13 per every 100,000 adults, according to the study. Additionally, for every 1 microgram increase in particulate matter per cubic meter of air, heart disease deaths decreased by approximately 39 deaths per 100,000 adults. 

"Given the potential cardiovascular benefits of higher greenness measures, it's important that dialogue about improved health and quality of life include environmental policies that support increasing greenness. Policymakers should support greenness through efforts that promote environmental justice through equitable access to green spaces, clean air and clean water, as well as minimizing exposure to environmental hazards," said William Aitken, MD, a cardiology fellow with the University of Miami Miller School of Medicine and UM/Jackson Memorial Hospital in Miami, Florida, in a press release.

Study limitations included that it was cross-sectional and used a total of combined cardiovascular disease death rates, according to the study. 

REFERENCE:
More green spaces can help boost air quality, reduce heart disease deaths [News Release] November 9, 2020; Dallas, TX. Accessed November 11, 2020. https://www.eurekalert.org/pub_releases/2020-11/aha-mgs110220.php.