The asthmatic patients with Covid-19 They do not have a greater risk of being hospitalized compared to non-asthmatics and their risk of being intubated is not greater than the group of patients admitted to hospital for coronavirus, according to a study in the Annals of the American Thoracic Society (ANNALATS). Even so, asthmatics should continue to take extreme preventive measures against Covid-19 consisting of 3 M (meters away, hand washing and use of a mask) and 3 C (avoid closed, crowded places and close contact).
People with respiratory diseases are not exempt from the use of a mask, according to the recommendations of the Spanish Society of Pulmonology and Thoracic Surgery (SEPAR).
«The results of this study are of interest to our asthmatics, because they indicate that are not at greater risk than the general population of being hospitalized and intubated and, therefore, they can help reduce the anxiety of these patients in the face of Covid-19. But they should not take them to lower their guard, because they can end up in the hospital like other patients with Covid-19 and, therefore, pulmonologists must emphasize that they are not exempt from using masks, like other patients with other respiratory diseases, “says the Dr. Marina Blanco Aparicio, pulmonologist and coordinator of the Asthma Area of SEPAR.
There are risk factors for severe Covid-19, such as obesity, hypertension or diabetes. Until now, the CDC (Center for Disease Control) in the United States, assumed that people with asthma had a higher risk of being hospitalized or suffering from severe forms of Covid-19, but the low number of asthmatics among those hospitalized in many International studies have questioned this and led to the study of whether this risk is overestimated.
Therefore, the ANNALSATS has compared the prevalence of asthma among patients hospitalized for Covid-19, reported in 15 studies from different countries around the world, with the prevalence of the disease in the general population and the average prevalence of asthma in hospitalized patients flu in the last 4 years. During the 2019-2020 flu season, 24.1% of people hospitalized with the flu had asthma, slightly higher than the average of the previous 4 years, from 2016-2020, when it was 21%. This prevalence is much higher than the combined prevalence estimate of asthma in hospitalized for Covid-19 in the 15 studies analyzed, which was 6.8%.
«It seems that the proportion of asthmatics among hospitalized patients with Covid-19 is similar to the prevalence of asthma in the population in each place where studies have been carried out, despite initial concerns about comorbidity and mortality in patients with asthma and Covid-19. Instead, asthmatics are more likely to be admitted for the fluas more than 20% of those hospitalized for the flu in the US have asthma. It is crucial that they continue to maximize their preventive care, especially in this context of a pandemic, that they wear a mask, take their usual medication and get a flu shot», Adds Dr. Blanco.
The new study at ANNALATS has also done a cross-sectional analysis of 436 Covid-19 patients admitted to the University of Colorado Hospital on the probability of intubating asthmatics versus non-asthmatics. Of these 436 patients, 239 were men and 195 women, with a mean age of 54.7 years and an age range of 19 to 100 years. 12% had asthma, which is consistent with the prevalence in the general population.
Of all the patients, 67.2% did not need intubation due to Covid-19 compared to 32.8% who did. It should be noted that with respect to this average of the sample in general, asthmatic patients required less intubation: it was only necessary in 27.9% of asthmatics, compared to 72.1% who did not need it. On the other hand, there were more non-asthmatics who needed intubation, 33.6%, compared to 66.4% of non-asthmatics who did not need it.
Admissions to ICU
On the other hand, 39.6% of the patients had to be admitted to an intensive care unit (ICU), while 60.4% did not. Proportionally, there were fewer admissions of asthmatics to the ICU, 34.1%, while 65.9% did not enter. In contrast, more non-asthmatic patients were admitted to the ICU, 40.4%, while 59.6% of non-asthmatics did not require this care resource.
The authors point out that a possible explanation for why Covid-19 is not associated with higher rates of hospitalization is because these may depend on the distribution of the receptor ACE2 in the epithelium of the airways. In diabetes and hypertension they can increase the expression of ACE2, while inhaled corticosteroids (ICS), which are used to treat asthma, may decrease ACE2 expression, which would make viral entry difficult. Patients with asthma, in general, and in particular asthmatics with a predominantly allergic phenotype, may have a significantly lower expression of ACE2.
Unlike asthma, having chronic obstructive pulmonary disease (COPD) does increase the risk of more serious forms of Covid-19 severe among hospitalized patients, and this comorbidity is associated with increased ACE2 expression in lung tissue and small airways. However, the authors say that the contribution of the ACE2 receptor to expression levels, general susceptibility to COVID-19, and the severity of this disease is unclear and more research in asthma and in general still needs to be done. They also admit that their findings come from an insufficient sample and that more research on asthma and the risk of intubation due to Covid-19 is needed to confirm their findings.