The results of the first studies and what has been observed in recent months in Spanish hospitals indicate that patients suffering from chronic obstructive pulmonary disease (COPD) run a risk of being infected by the SARS-CoV-2 coronavirus similar to that of the general population . However, those who are admitted to hospitals because of COVID-19, the disease that causes this microorganism, have a worse prognosis than average. Research confirms that in the most severe cases, the coronavirus triggers what is called a cytokine storm in the body. These proteins, also called cytokines, help fight infection, but when too many are activated, the immune system ends up attacking the body and generating an uncontrolled inflammatory process that can be fatal.
More details of this phenomenon in patients with COVID-19 remain to be known and understood, but clinical observations suggest that when the immune response does not control the virus – for example, in the case of older people with a weakened immune system – , it spreads more efficiently and damages the lungs. It causes hyperinflammation of such organs that would be associated with acute respiratory distress syndrome or adult respiratory distress syndrome (ARDS), described as the main cause of death from COVID-19.
Previous respiratory diseases: a risk factor?
Paradoxically, people with chronic respiratory diseases are not being particularly affected by the new virus that has turned the world upside down. The data available to date show that the most frequent comorbidities (the presence of coexisting or additional diseases in relation to the initial diagnosis) in those hospitalized with COVID-19 are high blood pressure, cardiovascular diseases, diabetes and smoking . Because individuals with chronic respiratory ailments – especially asthma and COPD – are more susceptible to viral infections, they were considered a potentially more vulnerable group to SARS-CoV-2 infection. But experts say that “to date there is no data that has confirmed this suspicion.”
In a recent online seminar organized by the Spanish Society of Primary Care Physicians (SEMERGEN), José Tomás Gómez Sáenz, coordinator of the Working Group of this, affirmed that patients with respiratory diseases “do not do particularly badly with this new ailment ”. Why? “Maybe they have been more protected from the beginning because of the fear of catching it, or maybe their treatments work. A clear explanation has not yet been found ”. The data collected in Spain indicate that the percentage of people with COPD admitted for COVID-19 is not higher in relative terms than that of the general population. In the largest series published to date, of 1590 cases analyzed, only 24 – 1.5% – had COPD, and none had asthma.
What has been proven is that, as expected, having chronic obstructive pulmonary disease is a bad thing when the coronavirus enters the equation: “In general, those affected have a worse prognosis, and their mortality rate is higher,” he says. Marina Blanco, coordinator of the Asthma Area of the Spanish Society of Pulmonology and Thoracic Surgery (SEPAR). For his part, Leovigildo Ginel, secretary of the SEMERGEN Respiratory Working Group, clarifies that “patients with chronic respiratory ailments do not have a greater risk of being infected by the SARS-CoV-2 virus, and the way in which the COVID-19 in them does not differ from that of the rest of the population. The important thing is that such chronic diseases are well controlled; in this sense, the main recommendation is that patients correctly comply with their usual treatments ”.
In addition, Dr. Ginel recommends that both asthmatics and COPD sufferers “use pressurized cartridge inhalers with an inhalation chamber, instead of nebulizers, since the latter produce aerosols in the environment that increase the chances of contagion by SARS-CoV-2 ”. If they experience an acute worsening of their symptoms, they should use rescue medication (short-acting bronchodilators) together with specific measures for each disease.
Dr. Blanco has observed in an in vitro study that the corticosteroids that COPD patients usually inhale decrease the viral replication of SARS-CoV-2. “The results will have to be confirmed, but this could explain why there is a lower percentage of COVID-19 cases among these people than in the rest of the population. “There is another theory that explains this phenomenon,” he adds, “but it affects a minority of patients and cannot be extrapolated. Some people with COPD take azithromycin three days a week. ” It is an antibiotic that is being used to stop COVID-19, so there could be a link.
What does seem very clear is that the disease caused by the new coronavirus that emerged in China at the end of 2019 is more likely to be serious in the case of COPD patients and smokers. Both have a greater number of receptors for angiotensin-converting enzyme 2 (ACE-2) in the bronchial epithelial cells of the lower respiratory tract, the door that SARS-CoV-2 opens to penetrate cells where it replicates. According to Dr. Blanco, “this may explain the fact that the disease is more dangerous in COPD patients. What we do not know is whether the treatments based on bronchodilators or the inhalation of corticosteroids can modulate the expression of these receptors ”.
The respiratory comorbidities of COVID-19
When two or more diseases coincide in a person, we speak of comorbidity. Sometimes these ailments interact and worsen the evolution of one and the other. Julio Ancochea, head of the Pneumology Service of the Hospital Universitario de La Princesa (Madrid), tells VERY that in his center and in the case of COVID-19 they emphasize these comorbidities: cardiovascular ailments, hypertension and diabetes ; and not so much in asthma and COPD, “which are in the minority.”
As he says, “we have reviewed a study published in the journal The Lancet Respiratory Medicine that analyzed whether these respiratory ailments and their treatments were risk factors in patients from China, Taiwan, Hong Kong, Canada … The conclusion is that, within comorbidities, COPD and asthma are very rare ”. Why? Ancochea explains it to us based on these three factors:
Underdiagnosis : “In Spain these diseases are rarely diagnosed. And in China even less. If the ailment is not previously registered in a person, it is not recorded ”.
Immune response : “Some specialists have the theory that patients suffering from asthma and COPD have a particular immune response against SARS-CoV-2. However, it is a fact that has not yet been proven.
The treatments : “Many people with strong asthma and COPD symptoms inhale corticosteroids, often associated with bronchodilators. To what extent do these inhaled corticosteroids exert an anti-inflammatory effect that can inhibit virus replication and the inflammatory phase with cytokine production? It is not at all clear, but it is a hypothesis that a few researchers maintain ”.
By Sandra Pulido
