Drew B Day1, Merlise A Clyde2, Jianbang Xiang3,4, Feng Li5, Xiaoxing Cui1, Jinhan Mo3,4, Jicheng Gong6, Charles J Weschler3,4,7, Yinping Zhang3,4, Junfeng Jim Zhang1,6,8. 1. Global Health Institute and Nicholas School of the Environment, Duke University, Durham, NC, USA. 2. Department of Statistical Science, Duke University, Durham, NC, USA. 3. Department of Building Science, Tsinghua University, Beijing 100084, China. 4. Beijing Key Laboratory of Indoor Air Quality Evaluation and Control, Beijing 100084, China. 5. Department of Respiratory Medicine, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai 200030, China. 6. College of Environmental Sciences and Engineering and Beijing Innovation Center for Engineering Science and Advanced Technology, Peking University, Beijing 100871, China. 7. Environmental and Occupational Health Sciences Institute, Rutgers University, Robert Wood Johnson Medical School, Piscataway, NJ, USA. 8. Duke Kunshan University, Kunshan 215347, China.
Abstract
BACKGROUND: Studies have suggested that age increases susceptibility to ozone-associated mortality, but the underlying mechanisms are unclear. In a previous study, personal exposure to ozone was significantly associated with a platelet activation biomarker, plasma soluble P-selectin (sCD62P), and blood pressure in 89 healthy adults, aged 22-52 years. The present study examines whether age modifies these associations in the same adults and in additional adults. METHODS: Interaction terms of age and exposure were analyzed using hierarchical Bayesian mixed effects ridge regressions. Data from a similar additional study involving 71 healthy participants, aged 19-26 years, were pooled with the data from the first study to evaluate age effect modification when more young adults were added to the analysis. RESULTS: In the 89 adults, significant age interactions were observed for past 24-hour and 2-week ozone exposures and sCD62P. Based on the pooled data (89 plus 71 adults), a 10 ppb increase in 24-hour ozone exposure was associated with increases in sCD62P and systolic blood pressure (SBP) by 22.3% (95% CI: 14.3%, 31.2%) and 1.35 (-0.18, 2.84) mmHg, respectively, at age 25; these values increased to 48.6% (32.7%, 65.1%) and 4.98 (2.56, 7.35) mmHg, respectively, at age 40. CONCLUSIONS: These results mechanistically suggest that increasing age enhances cardiovascular effects of ozone.
BACKGROUND: Studies have suggested that age increases susceptibility to ozone-associated mortality, but the underlying mechanisms are unclear. In a previous study, personal exposure to ozone was significantly associated with a platelet activation biomarker, plasma soluble P-selectin (sCD62P), and blood pressure in 89 healthy adults, aged 22-52 years. The present study examines whether age modifies these associations in the same adults and in additional adults. METHODS: Interaction terms of age and exposure were analyzed using hierarchical Bayesian mixed effects ridge regressions. Data from a similar additional study involving 71 healthy participants, aged 19-26 years, were pooled with the data from the first study to evaluate age effect modification when more young adults were added to the analysis. RESULTS: In the 89 adults, significant age interactions were observed for past 24-hour and 2-week ozone exposures and sCD62P. Based on the pooled data (89 plus 71 adults), a 10 ppb increase in 24-hour ozone exposure was associated with increases in sCD62P and systolic blood pressure (SBP) by 22.3% (95% CI: 14.3%, 31.2%) and 1.35 (-0.18, 2.84) mmHg, respectively, at age 25; these values increased to 48.6% (32.7%, 65.1%) and 4.98 (2.56, 7.35) mmHg, respectively, at age 40. CONCLUSIONS: These results mechanistically suggest that increasing age enhances cardiovascular effects of ozone.
Authors: Massimo Stafoggia; Francesco Forastiere; Annunziata Faustini; Annibale Biggeri; Luigi Bisanti; Ennio Cadum; Achille Cernigliaro; Sandra Mallone; Paolo Pandolfi; Maria Serinelli; Roberta Tessari; Maria Angela Vigotti; Carlo A Perucci Journal: Am J Respir Crit Care Med Date: 2010-03-25 Impact factor: 21.405
Authors: Sandrah P Eckel; Thomas A Louis; Paulo H M Chaves; Linda P Fried; And Helene G Margolis Journal: Am J Epidemiol Date: 2012-07-18 Impact factor: 4.897
Authors: Urmila P Kodavanti; Ronald Thomas; Allen D Ledbetter; Mette C Schladweiler; Jonathan H Shannahan; J Grace Wallenborn; Amie K Lund; Matthew J Campen; Elizabeth O Butler; Reddy R Gottipolu; Abraham Nyska; Judy E Richards; Deborah Andrews; Richard H Jaskot; John McKee; Sainath R Kotha; Rishi B Patel; Narasimham L Parinandi Journal: Environ Health Perspect Date: 2010-10-27 Impact factor: 9.031