Siqi Zhang1, Kathrin Wolf2, Susanne Breitner3, Florian Kronenberg4, Massimo Stafoggia5, Annette Peters6, Alexandra Schneider7. 1. Institute of Epidemiology, Helmholtz Zentrum München, Neuherberg, Germany. Electronic address: siqi.zhang@helmholtz-muenchen.de. 2. Institute of Epidemiology, Helmholtz Zentrum München, Neuherberg, Germany. Electronic address: kathrin.wolf@helmholtz-muenchen.de. 3. Institute of Epidemiology, Helmholtz Zentrum München, Neuherberg, Germany. Electronic address: susanne.breitner@helmholtz-muenchen.de. 4. Division of Genetic Epidemiology, Department of Medical Genetics, Molecular and Clinical Pharmacology, Medical University of Innsbruck, Innsbruck, Austria. Electronic address: Florian.Kronenberg@i-med.ac.at. 5. Department of Epidemiology, Lazio Regional Health Service, Local Health Unit ASL RM1, Rome, Italy. Electronic address: m.stafoggia@deplazio.it. 6. Institute of Epidemiology, Helmholtz Zentrum München, Neuherberg, Germany. Electronic address: peters@helmholtz-muenchen.de. 7. Institute of Epidemiology, Helmholtz Zentrum München, Neuherberg, Germany. Electronic address: alexandra.schneider@helmholtz-muenchen.de.
Abstract
BACKGROUND: Ankle-brachial index (ABI) has been linked to the risk of cardiovascular events. However, the association between long-term exposure to air pollution and abnormal ABI has not been fully investigated. METHODS: This cross-sectional study involved 4544 participants from the KORA Study (2004-2008) in the region of Augsburg, Germany. Participants' residential annual mean concentrations of particulate matter (PM) and nitrogen dioxide (NO2) were predicted with land-use regression models, and the traffic information was collected from geographic information systems. We applied multinomial logistic regression models to assess the effects of air pollution on the prevalence of low and high ABI, and quantile regression models to explore the non-monotonic relationship between air pollution and ABI. We also examined effect modification by individual characteristics. RESULTS: Long-term exposure to PM with an aerodynamic diameter ≤ 10 μm (PM10) and ≤ 2.5 μm (PM2.5) was significantly associated with a higher prevalence of low ABI, with the respective odds ratios (ORs) of 1.82 (95%CI: 1.11-2.97) and 1.59 (95%CI: 1.01-2.51) for a 5th to 95th percentile increment in pollutants. Positive associations with the prevalence of high ABI were observed for PM (e.g., PM10: OR = 1.63, 95%CI: 1.07-2.50) and NO2 (OR = 1.84, 95%CI: 1.15-2.94). Quantile regression analyses revealed similar non-monotonic results. The effects of air pollution on having abnormal ABI were stronger in physically inactive, hypertensive, or non-diabetic participants. CONCLUSIONS: Long-term exposure to PM and NO2 was associated with a higher prevalence of both low and high ABI, indicating the adverse effects of air pollution on atherosclerosis and arterial stiffness in the lower extremities.
BACKGROUND: Ankle-brachial index (ABI) has been linked to the risk of cardiovascular events. However, the association between long-term exposure to air pollution and abnormal ABI has not been fully investigated. METHODS: This cross-sectional study involved 4544 participants from the KORA Study (2004-2008) in the region of Augsburg, Germany. Participants' residential annual mean concentrations of particulate matter (PM) and nitrogen dioxide (NO2) were predicted with land-use regression models, and the traffic information was collected from geographic information systems. We applied multinomial logistic regression models to assess the effects of air pollution on the prevalence of low and high ABI, and quantile regression models to explore the non-monotonic relationship between air pollution and ABI. We also examined effect modification by individual characteristics. RESULTS: Long-term exposure to PM with an aerodynamic diameter ≤ 10 μm (PM10) and ≤ 2.5 μm (PM2.5) was significantly associated with a higher prevalence of low ABI, with the respective odds ratios (ORs) of 1.82 (95%CI: 1.11-2.97) and 1.59 (95%CI: 1.01-2.51) for a 5th to 95th percentile increment in pollutants. Positive associations with the prevalence of high ABI were observed for PM (e.g., PM10: OR = 1.63, 95%CI: 1.07-2.50) and NO2 (OR = 1.84, 95%CI: 1.15-2.94). Quantile regression analyses revealed similar non-monotonic results. The effects of air pollution on having abnormal ABI were stronger in physically inactive, hypertensive, or non-diabeticparticipants. CONCLUSIONS: Long-term exposure to PM and NO2 was associated with a higher prevalence of both low and high ABI, indicating the adverse effects of air pollution on atherosclerosis and arterial stiffness in the lower extremities.