Asthma is not a risk factor for severity of SARS-CoV-2 infection in the Mexican population

This study aims to assess the association between asthma and severity of COVID-19 in the Mexican population.

The data from a national database of confirmed patients diagnosed with COVID-19, who attended from February to June 2020, were analyzed in a retrospective cohort study. Patients with and without asthma were compared concerning hospitalization, pneumonia, endotracheal intubation, and death related to COVID-19. Other covariates (age, sex, indigenous group, and comorbidity) were included in various logistic regression models.

Asthma was associated with a lower risk of hospitalization (OR = 0.71, 95% CI 0.66 to 0.76), lower risk of pneumonia (OR = 0.75, 95% CI 0.69 to 0.81), and lower risk of endotracheal intubation (OR = 0.79, 95% CI 0.63 to 0.98). In addition, asthma decreased the risk of death from COVID-19 (OR = 0.73, 95% CI 0.65 to 0.82). In a subgroup analysis, the same association was observed in patients who required hospitalization (OR = 0.79, 95% CI 0.69 to 0.90), while in non-hospitalized patients, associations were inconsistent according to the covariates introduced in the models. There was no association between asthma and death in patients admitted to the intensive care unit (ICU), however, asthma significantly reduced the risk of death in the hospitalized patients who did not require ICU.

Our results suggest that patients with asthma are less likely to require hospitalization, develop pneumonia, need tracheal intubation or die from COVID-19 as compared to patients without asthma.