How Is Rhinitis And Asthma Related?
The relationship between rhinitis and asthma has long been known empirically in medical science. It is not uncommon for an asthmatic patient to present in the spring with allergic signs in his upper respiratory tract. The same thing happens in reverse.
Now, where does this intrinsic link reside? For some researchers it is a common origin that is in the immune system; for others, it is the similar shape of the respiratory mucosa that is shared between the bronchi and the nose. Let’s see more about it.
What is rhinitis?
A rhinitis is an inflammation of the lining of the nose. It can respond to various etiological agents, but the end result is always an increase in size due to the accumulation of fluids and inflammatory cells based on an external agent or an internal stimulus.
There are infectious and non-infectious rhinitis. In the first case, a microorganism invades the nose and infects it, either a virus or a bacteria. The body reacts to colonization and sets in motion mechanisms for the expulsion of the intruding agent. That determines the inflammation.
In the case of non-infectious rhinitis, the most common is the allergic form, which is the one that appears to a greater extent in asthmatic patients. Without being a virus or a bacterium, the external agent is a particle that is recognized as foreign and is attacked. In times of plant sprouts, pollen is usually one of the causes.
What is asthma?
Bronchial asthma is an inflammation of the lining of the bronchial tubes with hyperresponsiveness. In other words, beyond the inflammatory process, the airways close abruptly and impede the normal flow of air.
It is classified within the obstructive and chronic respiratory diseases. Its course evolves in the form of acute episodes within a long term. Certain triggers of crises, such as cold or infections, are more common in winter, so this time is the one that affects these people the most.
The diagnosis of the pathology is usually made at an early age. These are children who start with bronchospasm when they do physical activity or when the weather drops their temperature. They are first treated with bronchodilators to evaluate their evolution; if attacks recur, asthma is diagnosed.
Gravity is not always the same, nor is evolution linear. There are people with mild forms of the condition, who perhaps only have one attack a year, while others go through an almost persistent state of shortness of breath.
Why is there a relationship between rhinitis and asthma?
The explanations for why patients with asthma often suffer from rhinitis are varied. It is estimated that up to 75% of asthmatics experience inflammation of the nasal mucosa. Conversely, those diagnosed with rhinitis have bronchospasm in 40% of cases. Let’s look at some theories about this link.
Air conditioning not
One of the explanations why people with rhinitis also have asthma is the lack of sufficient flow through the nose. As there is inflammation of the mucosa, these patients prefer to breathe through the mouth, which avoids humidification and heating of the air.
In this way, when cold and dry air reaches the bronchi, the airway tends to contract because this flow is identified as harmful. Various scientific studies have shown that bronchoconstriction increases in cold weather, for example, among snow and winter athletes.
Communication between mucosa
Investigations in both directions reveal the relationship between all parts of the respiratory mucosa. If a person is stimulated with allergens in the nose, it is very likely that the cells of the bronchi react in some way. Conversely, when the lower airway contracts, the nasal mucosa changes.
Part of the pathophysiological mechanism would be in the nervous communication and in the reactivity of the blood vessels. That’s what appears to be behind exercise-induced asthma, mediated by the rush of adrenaline and norepinephrine that is triggered by sports stimuli.
These neurotransmitters link rhinitis and asthma by causing the closure of the caliber of the blood vessels. Throughout the respiratory mucosa, this narrowing reduces circulation and the ability to respond to external agents.
The immune system and the relationship between rhinitis and asthma
A special type of white blood cell is eosinophils. They have a special role in mediating whole-body allergic reactions. On the one hand, researchers learned about its role in rhinitis, while on the other hand its role in asthma is also known.
It is assumed that, since it is a similar mechanism, it makes sense to assume that allergic reactions share the common pathway of these cells and that their increase in situations of combat with external agents is key.
In addition, the substances of inflammation are not static, but take advantage of the blood circulation to move, so they can pass from the nose to the bronchi.
Rhinitis and asthma: similar, but different
The relationship between rhinitis and asthma can be explained by various hypotheses, but that does not mean that it is the same condition. Some drugs used are similar, although the approach does not have the same protocols for one and the other.
It is essential that treating physicians distinguish one condition from the other, so that the therapy is correct. In any case, asthmatic patients must learn to manage a rhinitis crisis, as they have a high probability of suffering from the disorder.
