ABSTRACT
Objective. To analyze the relationship between chronic exposures to air pollution with Covid-19 death rate in Mexican cities. Materials and methods. Ecological study in 25 Mexican cities using the report of daily Covid-19 deaths (from February to June 2020) and validated data of air pollutants, considering average concentrations in each city for the last year. Poisson regression models using generalized additive models with adjustment variables (GAM) were used. Results. A significant increase of 3.5% (95% CI 2.3-4.7) was found in Covid-19 death rate for each 1 mu g/m(3) in annual concentration of NO2. The association with PM2.5 was not significant, with an increase of 1.8% for each 1 mu g/m(3). Conclusions. Results suggest an association between Covid-19 mortality and chronic exposure to NO2. This first approximation of the risk associated with air pollution requires a more precise analysis, but is consistent with what was observed in other studies.