Short-Term Effects of Nitrogen Dioxide on Mortality and Susceptibility Factors in 10 Italian Cities: The EpiAir Study

• Published in: Environmental health perspectives Vol. 119; no. 9; pp. 1233 - 1238
• Main Authors: Chiusolo, Monica, Cadum, Ennio, Stafoggia, Massimo, Galassi, Claudia, Berti, Giovanna, Faustini, Annunziata, Bisanti, Luigi, Vigotti, Maria Angela, Dessi, Maria Patrizia, Cernigliaro, Achille, Mallone, Sandra, Pacelli, Barbara, Minerba, Sante, Simonato, Lorenzo, Forastiere, Francesco
• Format: Journal Article
• Language: English
• Published: Research Triangle Park, NC National Institute of Environmental Health Sciences 01-09-2011; US Department of Health and Human Services
• Subjects: Adult; Aged; Aged, 80 and over; Air; Air Pollutants - toxicity; Air pollution; Air Pollution - adverse effects; Biological and medical sciences; Cardiovascular Diseases - mortality; Chemical and industrial products toxicology. Toxic occupational diseases; Chronic diseases; Cross-Over Studies; Death; Demographic aspects; Diabetes; Diabetes Mellitus - mortality; Dioxides; Environment. Living conditions; Environmental Exposure - statistics & numerical data; Environmental pollutants toxicology; Female; Forecasts and trends; Gas, fumes; Health aspects; Heart; Hospital admissions; Hospitalization - statistics & numerical data; Humans; Italy; Italy - epidemiology; Male; Medical sciences; Metropolitan areas; Middle Aged; Mortality; Myocardial ischemia; Nitrogen; Nitrogen dioxide; Nitrogen Dioxide - analysis; Nitrogen Dioxide - toxicity; Ozone - analysis; Ozone - toxicity; Particulate Matter - analysis; Particulate Matter - toxicity; Population Surveillance; Public health. Hygiene; Public health. Hygiene-occupational medicine; Respiratory Tract Diseases - mortality; Socioeconomic Factors; Time Factors; Toxicology; Urban Health - statistics & numerical data; Italy; Europe; Short term; Toxic gas; Italian; Statistical analysis; Urban environment; susceptibility; Mortality; Risk; Exposure; Case control study; Epidemiology; outdoor air pollution; short-term exposure; Outside air; Analysis method; Health and environment; Predisposition; Environment; Case-crossover study; Air pollution; case-crossover analysis; Nitrogen dioxide; environmental epidemiology; Public health
• ISSN: 0091-6765; 1552-9924
• DOI: 10.1289/ehp.1002904

Background: Several studies have shown an association between nitrogen dioxide (NO₂) and mortality. In Italy, the EpiAir multicentric study, "Air Pollution and Health: Epidemiological Surveillance and Primary Prevention," investigated short-term health effects of air pollution, including NO₂. Objectives: To study the individual susceptibility, we evaluated the association between NO₂ and cause-specific mortality, investigating individual sociodemographic features and chronic/acute medical conditions as potential effect modifiers. Methods: We considered 276,205 natural deaths of persons > 35 years of age, resident in 10 Italian cities, and deceased between 2001 and 2005. We chose a time-stratified case-crossover analysis to evaluate the short-term effects of NO₂ on natural, cardiac, cerebrovascular, and respiratory mortality. For each subject, we collected information on sociodemographic features and hospital admissions in the previous 2 years. Fixed monitors provided daily concentrations of NO₂, paniculate matter ≤ 10 μm in aerodynamic diameter (PM₁₀) and ozone (O₃). Results: We found statistically significant associations with a 10-μg/m³ increase of NO₂ for natural mortality [2.09% for lag 0-5; 95% confidence interval (CI), 0.96-3.24], for cardiac mortality (2.63% for lag 0-5; 95% CI, 1.53-3.75), and for respiratory mortality (3.48% for lag 1-5; 95% CI, 0.75-6.29). These associations were independent from those of PM₁₀ and O₃. Stronger associations were estimated for subjects with at least one hospital admission in the 2 previous years and for subjects with three or more specific chronic conditions. Some cardiovascular conditions (i.e., ischemie heart disease, pulmonary circulation impairment, heart conduction disorders, heart failure) and diabetes appeared to confer a strong susceptibility to air pollution. Conclusions: Our results suggest significant and likely independent effects of NO₂ on natural, cardiac, and respiratory mortality, particularly among subjects with specific cardiovascular preexisting chronic conditions and diabetes.