Greenness on mortality of infant and under-5 child: A nationwide study in 147 Chinese cities

Abstract

Background: Higher greenness was associated with a lower risk of adult mortality. However, the effects of greenness on the mortality of infant and child under-5 have not been fully examined. Objectives: The association of greenness on the infant mortality rate (IMR) and child under-5 mortality rate (U5MR) in 147 Chinese cities from 2009 to 2020 was evaluated. Methods: Average and maximum annual population-weighted greenness, IMR (per 1000 live births), and U5MR (per 1000 live births) in 147 cities from 2009 to 2020 were collected, and a longitudinal panel study was conducted. Greenness exposure was evaluated using satellite-derived data at a spatial resolution of 250 m ×250 m in urban regions, and linear mixed-effect models were applied to assess the associations between greenness and IMR or U5MR in China. Results: This national study showed that long-term exposure to greenness was associated with lower IMR and U5MR, respectively. Specifically, a 0.1 increase of Normalized Difference Vegetation Index (NDVI) in greenness was statistically significant with a decrease in IMR (-1.05 ‰, 95 % CI: −1.48, −0.63 ‰) and U5MR (-1.82 ‰, 95 % CI: −2.39, −1.25 ‰) in fully-adjusted model, respectively. In the stratified analyses, greenness effects on U5MR in the western (-2.33 ‰, 95 % CI: −3.43, −1.23 ‰) and central regions (-2.06 ‰, 95 % CI: −3.01, −1.10 ‰) were stronger than that in the eastern region (-0.86 ‰, 95 % CI: −1.66, −0.07 ‰). Conclusions: This nationwide study indicated that exposure to higher greenness was associated with lower mortality rates in infant and child under-5 in China.

Keywords

• Greenness
• Infant mortality rate
• Under-5 mortality rate
• Nationwide study