Ambient particulate matter and surrounding greenness in relation to sleep quality among pregnant women: A nationwide cohort study

Dirga Kumar Lamichhane; Eunhee Ha; Yun-Chul Hong; Dong-Wook Lee; Myung-Sook Park; Sanghwan Song; Suejin Kim; Woo Jin Kim; Jisuk Bae; Hwan-Cheol Kim; Ko-CHENS Study Group

doi:10.1016/j.heliyon.2024.e26742

Ambient particulate matter and surrounding greenness in relation to sleep quality among pregnant women: A nationwide cohort study

Heliyon. 2024 Feb 20;10(5):e26742. doi: 10.1016/j.heliyon.2024.e26742. eCollection 2024 Mar 15.

Authors

Dirga Kumar Lamichhane^{1

2}, Eunhee Ha³, Yun-Chul Hong⁴, Dong-Wook Lee¹, Myung-Sook Park⁴, Sanghwan Song⁵, Suejin Kim⁵, Woo Jin Kim⁶, Jisuk Bae⁷, Hwan-Cheol Kim¹; Ko-CHENS Study Group

Affiliations

¹ Department of Occupational and Environmental Medicine, Inha University School of Medicine, Incheon, Republic of Korea.
² Department of Psychiatry, Huntsman Mental Health Institute, University of Utah School of Medicine, Salt Lake City, UT, USA.
³ Department of Occupational and Environmental Medicine, Ewha Womans University School of Medicine, Seoul, Republic of Korea.
⁴ Institute of Environmental Medicine, Seoul National University Medical Research Center, Seoul, Republic of Korea.
⁵ Environmental Health Research Division, Department of Environmental Health Research, National Institute of Environmental Research, Ministry of Environment, Incheon, Republic of Korea.
⁶ Department of Internal Medicine and Environmental Health Center, Kangwon National University, Chuncheon, Republic of Korea.
⁷ Department of Preventive Medicine, Daegu Catholic University School of Medicine, Daegu, Republic of Korea.

Abstract

Background: Particulate air pollution and residential greenness are associated with sleep quality in the general population; however, their influence on maternal sleep quality during pregnancy has not been assessed.

Objective: This cross-sectional study investigated the individual and interactive effects of exposure to particulate matter (PM) air pollution and residential greenness on sleep quality in pregnant women.

Methods: Pregnant women (n = 4933) enrolled in the Korean Children's Environmental Health Study with sleep quality information and residential address were included. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI). The average concentrations of PM (PM_2.5 and PM₁₀) during pregnancy were estimated through land use regression, and residential greenness in a 1000 m buffer area around participants' residences was estimated using the Normalized Difference Vegetation Index (NDVI_1000-m). Modified Poisson regression models were used to estimate the associations between PM and NDVI and poor sleep quality (PSQI >5) after controlling for a range of covariates. A four-way mediation analysis was conducted to examine the mediating effects of PM.

Results: After adjusting for confounders, each 10 μg/m³ increase in PM_2.5 and PM₁₀ exposure was associated with a higher risk of poor sleep quality (relative risk [RR]: 1.06; 95% confidence interval [CI]: 1.01, 1.11; and RR: 1.09; 95% CI: 1.06, 1.13, respectively), and each 0.1-unit increase in NDVI_1000-m was associated with a lower risk of poor sleep quality (RR: 0.97; 95% CI: 0.95, 0.99). Mediation analysis showed that PM mediated approximately 37%-56% of the association between residential greenness and poor sleep quality.

Conclusions: This study identified a positive association between residential greenness and sleep quality. Furthermore, these associations are mediated by a reduction in exposure to particulate air pollution and highlight the link between green areas, air pollution control, and human health.

Keywords: Ambient particulate matter; Environment; Pregnant women; Sleep quality; Surrounding greenness.