Asthma Subgroups: Rhinitis Induced Asthma
Many people with breathing disorders — like asthma — also suffer from medical conditions that may make it hard to breathe through their noses, which might even make their asthma worse. The most common nasal conditions among the asthma population is allergic rhinitis, which may lead to a diagnosis of Rhinitis Induced Asthma. Here's all you need to know.
What causes a stuffy nose?
Exposure to asthma triggers causes a series of chemical reactions that cause airway inflammation and asthma symptoms. These same chemicals may also cause inflammation of the blood vessels in your nose and sinuses. This inflammation may cause symptoms -- such as a stuffy nose -- resulting in a diagnosis of rhinitis. To make matters worse, rhinitis sometimes leads to a diagnosis of sinusitis (often called rhinosinusitis).
So, what is rhinitis?
Rhinitis It's inflammation of the blood vessels in your nasal passages causing sneezing, along with a stuffy, runny, and itchy nose. It' can be...
Non-allergic Rhinitis A good example is when it's caused by a common cold. Anyone can develop this. In asthma, it's more common in adult-onset asthma than childhood-onset. Episodes are usually short-term. 1, 3-4
Allergic Rhinitis It affects 20% of the U.S. population and therefore is the most common form of the allergic disorder. However, it affects up to 80% of asthmatics. Children are exposed to allergens early in life, and so it is more likely to be diagnosed in childhood than adulthood and is commonly associated with childhood-onset asthma. In either case, it's caused by exposure to common allergens like pollen and mold spores. Episodes may be persistent (year long, long-term, chronic) or they may be seasonal (hence, it's often referred to as hay fever). It's often associated with itchy eyes, watery eyes, itchy throat, itchy ears, mouth breathing, poor sleep, and also asthma symptoms in those who have asthma. 1-4
What is sinusitis?
SinusitisIt's inflammation of the blood vessels in your sinuses resulting in sinus infections. Symptoms include post nasal drip, trouble breathing through your nose, pain, and loss of the ability to taste or smell things. It can occur in people without asthma. It can be present without rhinitis, and this usually occurs with adult-onset asthma. However, it's usually secondary to a diagnosis or rhinitis, hence the term rhinosinusitis.5-6It affects 5-10% of people. 8
Acute Sinusitis It may be short-term, such as during a cold. It's usually caused by a virus and sometimes a bacteria. 6
Chronic Sinusitis (Rhinosinusitis) Or it may be long-term, such as when you're constantly exposed to allergens and have rhinitis. It may also be a common feature of Eosinophilic and Aspirin-Sensitive Asthma. 6 It may also be caused by other nasal abnormalities, such as a eviated septum or nasal polyps. 7 One study showed that up to 93% of asthmatics also had a diagnosis of chronic sinusitis, and another showed that 40% of those with chronic sinusitis also had asthma. A 12-year study showed that people diagnosed with chronic sinusitis have an elevated risk for developing asthma. 8
What are links between rhinitis, sinusitis, and asthma?
Studies show Allergic Rhinitis is very common in those diagnosed with Allergic Asthma, and uncontrolled rhinitis can lead to more severe asthma.This happens when inflammatory chemicals (like histamine and leukotrienes) get into the bloodstream and travel to the lungs (either by postnasal drip or via the bloodstream), thereby making inflammation there worse. This makes airways increasingly hypersensitive to asthma triggers. Many of these same chemicals can recruit other chemicals and cells (eosinophils) that may enhance the inflammatory response, resulting in persistent rhinitis and asthma symptoms. Another accepted theory is the one that involves reflexes.1-2, 4-5, 9
What are the pharyngobronchial and nasobronchial reflexes?
Of course this is just a theory, but it's suspected that anything that causes inflammation of the upper airways may also cause inflammation of the lower airways. In the case of rhinitis and sinusitis, the reflex may be instigated by post nasal drip. 1, 4, 8, 10
What are deviated septum and nasal polyps?
Deviated SeptumYour nasal septum is deviated to one side or the other, with the airflow blocked or obstructed on the one side, and this may be further obstructed by inflammation.
Nasal PolypsChronic inflammation in your nose or sinuses caused by rhinitis or sinusitis may contribute to polyps. Another thing that can contribute to polyps is eosinophilic asthma, where the polyps are eosinophilic in origin. In either case, polyps may block nasal passages making them feel stuffy.
How is Rhinitis Induced Asthma treated?
Treatment Studies show that treating rhinitis results in improved asthma control. 10Rhinitis can be treated by avoiding allergens or by taking medicines such as antihistamines (like Benadryl or Claritin), leukotriene antagonists (like Singulair), decongestants (like Sudafed), nasal washes, nasal corticosteroids, and other nasal sprays. It may also be treated with desensitization treatment (allergy shots). 4,Kim Sinusitis is treated similarly, although may also be treated with antibiotics if caused by a bacteria, and pain relievers (such as Tylenol) if pain or fever develop. Nasal abnormalities are treated with medicine and sometimes with surgery. 6, Hwang
What can we conclude here
The links between asthma and rhinitis have been apparent for many years, although it's only in recent years that the links have been confirmed by science. Most asthma experts recognize that treating one means diagnosing and treating the other. Some asthma experts now recognize this as it's own asthma subgroup: Rhinitis Induced Asthma.
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