Associations of street-view greenspace exposure with cardiovascular health (Life's Essential 8) among women in midlife.

Background: Many women experience suboptimal cardiovascular health (CVH) during midlife. Greenspace exposure has been inversely associated with cardiovascular disease because it may reduce harmful environmental exposures and promote healthy behaviors. Most prior studies used satellite-based rather than ground-level exposures and did not examine overall CVH.

Methods: We performed a longitudinal analysis of women in the Project Viva cohort based in Eastern Massachusetts. We applied deep learning algorithms to Google Street View images to derive metrics of visible trees, grass, and other greenspace within 500 m of participant's residential addresses in 2012-2016 (mean age 46 years). About five years later (mean age 51 years), participants completed questionnaires and research measurements including blood collection. We calculated CVH scores using Life's Essential 8 (LE8) construct (0-100 points, higher = better), which includes four behavioral (diet, physical activity, sleep, and avoidance of smoking) and four biomedical measures (body mass index, blood pressure, blood lipids, and blood glucose). We used linear regression models adjusted for age and both individual- and neighborhood-level socioeconomic status.

Results: Among 767 participants, 68% were non-Hispanic White, and 74% were college graduates. Mean (SD) CVH score was 72 (13) points. When including three greenspace components in the same model, higher % trees (per SD) was associated with higher overall CVH score (β = 2.4; 95% CI: 1.3, 3.5), as well as higher behavioral (β = 2.8; 95% CI: 1.4, 4.3) and biomedical (β = 2.8; 95% CI: 1.0, 4.7) sub-scores. Additionally, % other greenspace (per SD) was associated with better biomedical CVH scores (β = 2.2; 95% CI: 0.4, 3.9), whereas associations for % grass were non-significant. Higher % trees (per SD) was associated with higher scores for most individual CVH components, including diet (β = 2.1 points; 95% CI: 0.7, 3.4), physical activity (β = 4.0; 95% CI: 1.2, 6.9), sleep (β = 2.6; 95% CI: 0.9, 4.4), BMI (β = 5.8; 95% CI: 2.8, 8.8), and blood glucose (β = 2.2; 95% CI: 0.3, 4.2).

Conclusions: Greater street-view greenspace exposure, especially visible trees in streetscapes, was associated with better CVH among midlife women. Increasing trees in neighborhoods may be a valuable public health strategy to improve multiple metrics of cardiovascular health.