## 3 Results  
Our registry initially included 1069 adult patients with symptomatic SARS-CoV-2 infection. However, 134 individuals were excluded due to a missing molecular swab report after ED admission (38) or incomplete data (96). Overall, 83 patients with asthma were identified (prevalence 8.9%). A total of 83 COVID-19 patients without asthma--matched to cases for age, sex, race, and enrollment period--served as the controls (Figure 1). Table 1 shows the demographic data, clinical characteristics, home treatment with inhaled or systemic steroids, values of the most common markers of acute inflammation (C-reactive protein, CRP, mg/L), and oxygenation (PaO\({}_{2}\)/FiO\({}_{2}\)) in the asthma cases and the controls. Although not specifically matched, the number of individuals who received the first vaccination in the last two weeks before hospitalization was the same (6%). The low vaccinated rate observed in the present study was consistent with the enrollment period (until January 2021). A significantly higher prevalence of arterial hypertension and multimorbidity was observed in the control group (33.7% vs. 55.4% and 36.1% vs. 57.8%, respectively; \(p\) = 0.005 for both analyzes). As expected, home treatment with inhaled corticosteroids (ICS) was significantly more common in the asthma group (50.6% vs. 3.6%;  
\(p\) < 0.001). No significant differences were observed between cases and controls regarding the other variables, including oxygenation parameters (PaO\({}_{2}\)/TiO\({}_{2}\)), inflammatory markers (CRP), and absolute number of circulating eosinophils. Slightly more patients with asthma were admitted to the hospital than the controls (70/83, 84.3% vs. 66/83, 79.5%), with no statistical differences (\(p\) = 0.52; OR 1.37; 95% CI 0.52-3.56; Table 2). The characteristics of the hospitalized cases and the controls were \begin{table}
\begin{tabular}{l c c c} \hline \hline \multicolumn{1}{c}{**Variables**} & \multicolumn{1}{c}{**Asthma**} & \multicolumn{1}{c}{**Controls**} & \\ \multicolumn{1}{c}{} & **(N = 83)** & **(N = 83)** & \multicolumn{1}{c}{\(p\)**Value**} \\ \hline Age (mean \(\pm\) SD, years) & 54.6 \(\pm\) 14.6 & 54.6 \(\pm\) 14.5 & ns \\ Sex, males (\%) & 42 (50.6\%) & 42 (50.6\%) & ns \\ Race: & & & \\ Caucasian (\%) & 74 (50.6\%) & 74 (50.6\%) & ns \\ Others (\%) & 9 (10.8\%) & 9 (10.8\%) & ns \\ Pandemic wave: & & & \\ First (\%) & 24 (28.9\%) & 24 (28.9\%) & ns \\ Second (\%) & 59 (71.1\%) & 59 (71.1\%) & ns \\ Vaccinated (first dose) (\%) & 5 (6\%) & 5 (6\%) & ns \\ BMI \(>\) 24.9 (\%) & 33 (39.8\%) & 38 (45.8\%) & ns \\ Current smokers (\%) & 13 (15.7\%) & 20 (24.1\%) & ns \\ Diabetes (\%) & 12 (14.5\%) & 16 (19.3\%) & ns \\ Hypertension (\%) & 28 (33.7\%) & 46 (55.4\%) & 0.005 \\ Cardiopathy (\%) & 6 (7.2\%) & 9 (10.8\%) & ns \\ COPD (\%) & 7 (8.4\%) & 4 (4.8\%) & ns \\ Multimorbidity (\%) & 30 (36.1\%) & 48 (57.8\%) & 0.005 \\ ICS (\%) & 42 (50.6\%) & 3 (3.6\%) & \textless{}0.001 \\ OCS (\%) & 6 (7.2\%) & 2 (2.4\%) & ns \\ PaO\({}_{2}\)/FiO\({}_{2}\) (mean \(\pm\) SD, mmHg) & 298.5 \(\pm\) 109.1 & 298.2 \(\pm\) 103.3 & ns \\ CRP (mean \(\pm\) SD, mg/L) & 64.2 \(\pm\) 73.7 & 68.6 \(\pm\) 74.9 & ns \\ AEC (mean \(\pm\) SD, cells/\(\mu\)L) & 42.0 \(\pm\) 78.4 & 41.2 \(\pm\) 51.3 & ns \\ AEC \(\geq\) 150 cells/\(\mu\)L (\%) & 4 (4.8\%) & 6 (7.2\%) & ns \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Characteristics of cases and controls admitted to our ED for symptomatic COVID-19. Abbreviations: SD, standard deviation; BMI, body mass index; COPD, chronic obstructive pulmonary disease; ICS, inhaled corticosteroids; OCS, oral corticosteroids; AEC, absolute eosinophil count. Figure 1: Flowchart of the study population. ED: emergency department. similar to those reported in Table 1, with significant differences in arterial hypertension, multimorbidity, and home ICS treatment with ICS. There were also no significant differences in the rate of critical COVID-19 (cases 21/70, 27.7% vs. controls 23/66, 34.8%; \(p\) = 0.50; OR 0.74; 95% CI 0.31-1.78).