Exploring vulnerability patterns in heat-related preterm birth: a multi-country multi-city analysis
- 1Centro de Investigación Mariña, Universidade de Vigo, Environmental Physics Laboratory (EPhysLab), Campus As Lagoas s/n, 32004 Ourense, Spain
- 2Institute of Social and Preventive Medicine (ISPM), University of Bern, Bern, Switzerland & Oeschger Center for Climate Change Research, University of Bern, Bern, Switzerland
- 3Department of Statistics and Operational Research, Universitat de València, Moliner, 50 46100, Valencia, Spain
- 4Spanish Consortium for Research on Epidemiology and Public Health (CIBERESP), Madrid, Spain
- 5Department of Global Environmental Health Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
- 6Air Health Science Division, Health Canada, Ottawa, Canada
- 7Institute of Family Medicine and Public Health, University of Tartu, Tartu, Estonia
- 8Swiss Tropical and Public Health Institute, Basel, Switzerland
- 9University of Basel, Basel, Switzerland
- 10Department of Geography, University of Santiago de Compostela, Santiago de Compostela, Spain
- 11Department of Epidemiology Lazio Regional Health Service, Rome, Italia
- 12Environmental and Occupational Medicine, and Institute of Occupational Medicine and Industrial Hygiene, National Taiwan University (NTU) and NTU Hospital, Taipei, Taiwan
- 13Department of Biostatistics and Bioinformatics, Rollins School of Public Health, Emory University, Atlanta, USA
- 14Department of Public Health and Clinical Medicine, Umeå University, Umeå, Sweden
- 15Department of Human Ecology, School of International Health, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
- 16Institute of Environmental Assessment and Water Research (IDAEA), Spanish Council for Scientific Research (CSIS), Barcelona, Spain
- 17The Health Environment Research-HER lab, Department of Population Health, Azrieli Faculty of Medicine, Bar-Ilan University, Tzfat, Israel
- 18Department of Environmental Health. Rollins School of Public Health, Emory University, Atlanta, USA
- 19Climate Change Research Centre, University of New South Wales, Sydney, Australia
- 20Centro Interdisciplinario de Cambio Global, Pontificia, Universidad Católica de Chile, Santiago, Chile
- *A full list of authors appears at the end of the abstract
Evidence suggests that high temperatures may trigger preterm birth (PTB), which is associated with a higher risk of infant mortality and morbidity during childhood and adult life. However, there is limited evidence on the role of sociodemographic factors on the vulnerability of pregnant women. In a multi-location setting, we aimed to assess 1) the effect of heat on PTB of different gestational ages (extreme, very, late, standard preterm births) and at-term births and 2) how mother and child characteristics (sex, ethnicity, parity, age, education, marital status, socioeconomic class) influence the association between heat and PTB.
The analysis included all singleton births born in the warm season (5 warmer months) in 243 cities in 13 countries between 1979-2019. A two-stage design was applied with conditional quasi-Poisson regression with distributed lag nonlinear models to estimate the association between daily mean temperature and PTB or at-term birth (lags 0-4 days) in each location and for each category of characteristic of the mother and child. Then, a random-effects multilevel metaanalytical model was applied to report overall effects and by country level. Extreme heat effects were measured as the percentage change (ch%, 95%CI) in the outcome when the mean temperature increased from 1% to the 95% percentile.
Heat was positively associated with all endpoints, except for extreme or very PTB whose risks were very imprecise, with larger risks for late-PTB (5%, 0.8-9.3) and smaller in at term births (2%, 1-3.1). Younger, Caucasian mothers and those with low socioeconomic class seemed to be more vulnerable to heat. Female fetal gender was associated with higher risk than males.
This is the largest multi-location study assessing vulnerability patterns of heat-related PTB. It emphasises the need to integrate evidence from vulnerability assessments in designing public health interventions to face climate change effects.
https://mccstudy.lshtm.ac.uk/
How to cite: Salvador, C., Iñiguez, C., Kim, Y., Lavigne, E., Orru, H., Ragettli, M. S., Royé, D., de’Donato, F., Leon Guo, Y.-L., Chang, H., Astrom, C., Konishi, S., Tobías, A., Agay-Shay, K., Scovronick, N., Singh, T., Valdes Ortega, N., and Vicedo-Cabrera, A. M. and the Multi-Country Multi-City Collaborative Research Network: Exploring vulnerability patterns in heat-related preterm birth: a multi-country multi-city analysis, EMS Annual Meeting 2024, Barcelona, Spain, 1–6 Sep 2024, EMS2024-938, https://doi.org/10.5194/ems2024-938, 2024.
