ABSTRACT
Introduction: Studies have found associations between air pollution and pneumonia and air pollution is an established risk factors for common COVID-19 complications including pneumonia. Additionally, air pollutants have been identified as possible risk factors for MS onset and relapses. To our knowledge, only one study explored the impact of air pollution on Covid-19 severity specifically among MS patients but has only focused on PM2.5 exposures. Aim(s): We aim to evaluate the association between long-term exposure to air pollution and COVID-19 severity, described as developing pneumonia in a population of COVID-19-positive MS patients. Method(s): Data on COVID-19 infection among MS patients were extracted from an Italian web-based platform (Musc-19). A casecontrol study was designed including patients with and without pneumonia at a case-control ratio of 1:2 and 615 patients were included. The included patients were asked to provide information on the geographical area where they had spent most time in the previous 5 years. When this information was missing, the address of the MS center was used as a proxy and evaluated in sensitivity analysis. Air quality was assessed as annual average particulate matter (PM2.5 and PM10) and Nitrogen Dioxide (NO2) ground-level concentrations derived from air quality model results as provided by the 'Copernicus Atmospheric Monitoring Service', and evaluated as categorical exposures (terciles). The association between pollutants and COVID-19 pneumonia was studied using logistic regression models, also adjusting for confounders (age, sex, BMI, comorbidities, EDSS, MS type, duration and treatments). Result(s): Detailed exposure was obtained for 491 patients, of whom 34% had pneumonia. Higher concentrations of air pollutants were associated with increased odds of developing COVID-19 pneumonia in both unadjusted and adjusted models (Adjusted models estimates: PM2.5: 2nd vs 1st tercile OR(95% CI)=2.09 (1.20;3.65), 3rd vs 1st tercile OR(95% CI)=2.26(1.29;3.96);PM10: 2nd vs 1st tercile OR(95% CI)=1.83(1.05;3.20), 3rd vs 1st tercile OR(95% CI)=2.12(1.22;3.68);NO2: 3rd vs 1st tercile OR(95% CI)=2.12(1.21;3.69)). Results remained consistent in the sensitivity analysis. Conclusion(s): Higher long-term concentrations of PM2.5, PM10 and NO2 were associated with COVID-19 pneumonia among MS patients. Urgent measures to reduce air pollution should be adopted especially to protect the most vulnerable population.
ABSTRACT
Introduction: Studies have pointed out that air pollution longterm exposure may play a role in the severity and prognosis of SARS-CoV-2 infections. Additionally, air pollution has been associated to MS prevalence and course. However, the role of air pollution in COVID-19 severity has never been explored specifically among MS patients. Aims: To explore the association between air pollution assessed by PM2.5 levels and COVID-19 severity among MS patients. Methods: Demographic and clinical characteristics as well as data about Covid-19 severity were extracted from an Italian webbased platform (Musc-19 project) containing clinician-reported data from 118 Italian MS centers. PM2.5 ground-level concentrations were derived from air quality model results, as provided by the 'Copernicus Atmospheric Monitoring Service' (CAMS). Ordered logistic regression models were used to assess the association between PM2.5 (continuous and in tertiles) and Covid-19 prognosis (defined on three levels as mild course, hospitalization, and intensive care unit (ICU) admission or death) while controlling for possible confounders. Results: PM2.5 concentrations were available for 1517 MS patients, of whom 1321(87%) were classified as mild Covid-19 cases, 172(11%) were hospitalized and 24(2%) were admitted to ICU or died. Higher concentrations of PM2.5 were associated with increased odds of developing a worst Covid-19 prognosis (10-unit increase in PM2.5: OR(95% CI)=1.76(1.16-2.67) p-value=0.008;3rd vs 1st tertile: OR(95% CI)=1.74(1.17-2.59) p-value=0.006). Results remained consistent when we included only the Covid-19 cases confirmed by a nasopharyngeal swab (N=1087). Conclusions: Higher concentrations of PM2.5 are associated with Covid-19 severity among MS patients. Further studies are needed to evaluate the impact of other air pollutants, but urgent measures to reduce air pollution must be surely adopted.
ABSTRACT
In this paper we critically review the work "Assessing nitrogen dioxide (NO2) levels as a contributing factor to coronavirus (COVID-19) fatality" (Ogen, 2020), stressing the fact that we think there are flaws in the published methodology. We do this as we think it is important, given the current deluge of 'COVID-19 related' publications, to clearly define what can be stated and what on the contrary, cannot be stated, due to limitations in terms of data quality and/or methodology.