Short-term effects of air pollution and noise on emergency hospital admissions in Madrid and economic assessment

Introduction: The aim of this study was to study the effect of air pollution and noise has on the population in Madrid Community (MAR) in the period 2013-2018, and its economic impact.Methods: Time series study analysing emergency hospital admissions in the MAR due to all causes (ICD-10: A00 -R99), respiratory causes (ICD-10: J00-J99) and circulatory causes (ICD-10: I00-I99) across the period 2013-2018. The main independent variables were mean daily PM2.5, PM10, NO2, 8-h ozone concentrations, and noise. We controlled for meteorological variables, Public Holidays, seasonality, and the trend and autoregressive nature of the series, and fitted generalised linear models with a Poisson regression link to ascertain the relative risks and attributable risks. In addition, we made an economic assessment of these hospitalisations.Results: The following associations were found: NO2 with admissions due to natural (RR: 1.007, 95% CI: 1.004-1.011) and respiratory causes (RR: 1.012, 95% CI: 1.005-1.019); 8-h ozone with admissions due to natural (RR: 1.049, 95% CI: 1.014-1.046) and circulatory causes (RR: 1.088, 95% CI: 1.039-1.140); and diurnal noise (LAeq7-23h) with admissions due to natural (RR: 1.001, 95% CI: 1.001-1.002), respiratory (RR: 1.002, 95% CI: 1.001-1.003) and circulatory causes (RR: 1.003, 95% CI: 1.002-1.005). Every year, a total of 8246 (95% CI: 4580-11,905) natural-cause admissions are attributable to NO2, with an estimated cost of close on euro 120 million and 5685 (95% CI: 2533-8835) attributed to LAeq7-23h with an estimated cost of close on euro 82 million.Conclusions: Nitrogen dioxide, ozone and noise are the main pollutants to which a large number of hospital-isations in the MAR are attributed, and are thus responsible for a marked deterioration in population health and high related economic impact.