Sara Conti1, Alessandra Lafranconi2, Antonella Zanobetti3, Carla Fornari4, Fabiana Madotto5, Joel Schwartz6, Giancarlo Cesana7. 1. Research Centre on Public Health. Department of Statistics and Quantitative Methods. University of Milano - Bicocca. Via Cadore 48, I-20052 Monza, (MB), Italy. Electronic address: sara.conti@unimib.it. 2. School of Hygiene and Preventive Medicine. Department of Health Sciences. University of Milano - Bicocca. Via Cadore, 48, I-20052 Monza, (MB), Italy. Electronic address: lafranconi.ale@gmail.com. 3. Department of Environmental Health, Harvard School of Public Health, P.O. Box 15698, Landmark Center-415-K, Boston, MA 02215, USA. Electronic address: azanobet@hsph.harvard.edu. 4. Research Centre on Public Health. Department of Statistics and Quantitative Methods. University of Milano - Bicocca. Via Cadore 48, I-20052 Monza, (MB), Italy. Electronic address: carla.fornari@unimib.it. 5. Research Centre on Public Health. Department of Statistics and Quantitative Methods. University of Milano - Bicocca. Via Cadore 48, I-20052 Monza, (MB), Italy. Electronic address: fabiana.madotto@unimib.it. 6. Department of Environmental Health, Harvard School of Public Health, P.O. Box 15698, Landmark Center-415-K, Boston, MA 02215, USA. Electronic address: joel@hsph.harvard.edu. 7. Research Centre on Public Health. Department of Statistics and Quantitative Methods. University of Milano - Bicocca. Via Cadore 48, I-20052 Monza, (MB), Italy. Electronic address: giancarlo.cesana@unimib.it.
Abstract
BACKGROUND: A few panel and toxicological studies suggest that health effects of particulate matter (PM) might be modified by medication intake, but whether this modification is confirmed in the general population or for more serious outcomes is still unknown. OBJECTIVES: We carried out a population-based pilot study in order to assess how pre-hospitalization medical treatments modify the relationship between PM<10 μm in aerodynamic diameter (PM10) and the risk of cardiorespiratory admission. METHODS: We gathered information on hospitalizations for cardiorespiratory causes, together with pre-admission pharmacological treatments, that occurred during 2005 in seven cities located in Lombardy (Northern Italy). City-specific PM10 concentrations were measured at fixed monitoring stations. Each treatment of interest was analyzed separately through a case-only approach, using generalized additive models accounting for sex, age, comorbidities, temperature and simultaneous intake of other drugs. Analyses were stratified by season and, if useful, by age and sex. RESULTS: Our results showed a higher effect size for PM10 on respiratory admissions in subjects treated with theophylline (Odds Ratio (OR) of treatment for an increment of 10 μg/m(3) in PM10 concentration: 1.119; 95% Confidence Interval (CI): 1.013-1.237), while for cardiovascular admissions treatment with cardiac therapy (OR: 0.967, 95% CI: 0.940-0.995) and lipid modifying agents (OR: 0.962, 95% CI: 0.931-0.995) emerged as a protective factor, especially during the warm season. Evidence of a protective effect against the pollutant was found for glucocorticoids and respiratory admissions. CONCLUSIONS: Our study showed that the treatment with cardiac therapy and lipid modifying agents might mitigate the effect of PM10 on cardiovascular health, while the use of theophylline seems to enhance the effect of the pollutant, possibly due to confounding by indication. It is desirable to extend the analyses to a larger population.
BACKGROUND: A few panel and toxicological studies suggest that health effects of particulate matter (PM) might be modified by medication intake, but whether this modification is confirmed in the general population or for more serious outcomes is still unknown. OBJECTIVES: We carried out a population-based pilot study in order to assess how pre-hospitalization medical treatments modify the relationship between PM<10 μm in aerodynamic diameter (PM10) and the risk of cardiorespiratory admission. METHODS: We gathered information on hospitalizations for cardiorespiratory causes, together with pre-admission pharmacological treatments, that occurred during 2005 in seven cities located in Lombardy (Northern Italy). City-specific PM10 concentrations were measured at fixed monitoring stations. Each treatment of interest was analyzed separately through a case-only approach, using generalized additive models accounting for sex, age, comorbidities, temperature and simultaneous intake of other drugs. Analyses were stratified by season and, if useful, by age and sex. RESULTS: Our results showed a higher effect size for PM10 on respiratory admissions in subjects treated with theophylline (Odds Ratio (OR) of treatment for an increment of 10 μg/m(3) in PM10 concentration: 1.119; 95% Confidence Interval (CI): 1.013-1.237), while for cardiovascular admissions treatment with cardiac therapy (OR: 0.967, 95% CI: 0.940-0.995) and lipid modifying agents (OR: 0.962, 95% CI: 0.931-0.995) emerged as a protective factor, especially during the warm season. Evidence of a protective effect against the pollutant was found for glucocorticoids and respiratory admissions. CONCLUSIONS: Our study showed that the treatment with cardiac therapy and lipid modifying agents might mitigate the effect of PM10 on cardiovascular health, while the use of theophylline seems to enhance the effect of the pollutant, possibly due to confounding by indication. It is desirable to extend the analyses to a larger population.