Aspirin-induced asthma

• What is Aspirin-Induced Asthma
• Statistics on Aspirin-Induced Asthma
• Risk Factors for Aspirin-Induced Asthma
• Progression of Aspirin-Induced Asthma
• Symptoms of Aspirin-Induced Asthma
• Clinical Examination of Aspirin-Induced Asthma
• How is Aspirin-Induced Asthma Diagnosed?
• Prognosis of Aspirin-Induced Asthma
• How is Aspirin-Induced Asthma Treated?
• Aspirin-Induced Asthma References

What is Aspirin-Induced Asthma

Aspirin-induced asthma is characterised by aggressive and continuous inflammation of the airways, leading to worsening of asthma, after ingestion of aspirin or other non-steroidal anti-inflammatory drugs (NSAIDs). There are many other terms for this condition, including:

• ASA-induced asthma;
• Aspirin triad;
• ASA sensitivity;
• ASA-intolerant asthma;
• ASA-exacerbated respiratory disease.

Aspirin-induced asthma has the most widespread use and acceptance in clinical medicine. As in asthma, this is a disease that occurs in the lungs.

Statistics on Aspirin-Induced Asthma

Aspirin-induced asthma is common among people with asthma as a disease. A Finland study concluded that the cases of aspirin-induced shortness of breath or asthma attacks was 1.2%. A study from Poland concluded that the cases was 4.3% in patients with a diagnosis of asthma. In Perth, Western Australia, the prevalence of chest symptoms triggered by aspirin was 10-11% amongst patients with asthma.

Risk Factors for Aspirin-Induced Asthma

The predisposing factors for this disease remain vague. Age is important, as the disease usually begins at 30-50 years old. However, all ages can be affected. Studies have indicated the possibility of genetic risk factors for this disease.

Progression of Aspirin-Induced Asthma

Aspirin-induced asthma develops following a characteristic sequence of events. At an average age of 30 years, persistent rhinitis (hayfever) will appear, followed by asthma, aspirin sensitivity and nasal polyps. The triad of asthma, aspirin sensitivity and nasal polyps are termed Samter’s triad.
The exact mechanism of this disease remains unknown, though continuing research has shed some light. It is thought that certain biochemical compounds in the body are either overproduced or underproduced, leading to imbalance of these compounds. This disease is thought to have an allergic component to the mechanism.

Symptoms of Aspirin-Induced Asthma

Possible signs include:

• Gradual or sudden onset of difficulty breathing;
• Cough, especially at night, and sometimes with phlegm;
• Rapid heart rate;
• Increased breathing rate;
• Increased blood pressure;
• Blue lips/tongue;
• Wheezing;
• Crackles (sounds heard in the chest through a stethoscope);
• Aspirin-induced hives;
• Nasal polyps.

How is Aspirin-Induced Asthma Diagnosed?

If a person with an asthma attack needs to be admitted to the hospital and the disease is severe enough, routine tests will be done. These include looking at the blood function, liver function, kidney function, lung function, and blood electrolytes. Usually an arterial blood gas test will be done to assess the concentration of oxygen and carbon dioxide in the blood.

Prognosis of Aspirin-Induced Asthma

Aspirin-induced asthma does not have a high death rate on its own and is not life-threatening. However, it can lead to significant inconvenience if left untreated. Symptoms of asthma attacks can be debilitating.

How is Aspirin-Induced Asthma Treated?

NSAID avoidance
As in other allergic diseases, it is important to avoid the medications known to cause the asthma attack. Aside from aspirin, other NSAIDs should bee avoided as well. NSAIDs are a group of drugs usually used as pain killers, including ibuprofen and diclofenac.
Although paracetamol (acetaminophen) is a generally safe substitute for pain relief, it does have weak cyclooxygenase inhibitory properties. As many as 7% of the patients who are sensitive to aspirin may react towards paracetamol if taken at high doses. Hence it is wise to avoid paracetamol as well.
Using COX-2 inhibitors
COX-2 inhibitors are drugs commonly used as pain relief, but work slightly differently to NSAIDs. Current studies suggest that COX-2 inhibitors such as celecoxib do not induce asthma attack in people with aspirin-induced asthma.
Aspirin desensitization
Desensitization involves using a protocol that requires 1-3 days of in-patient treatment with daily aspirin ingestion. This treatment is especially useful for people who require aspirin or other NSAIDs regularly for pain relief, such as people with concurrent joint conditions.
Sinus disease
People with inflammation or infection of the sinus are treated accordingly with antibiotics. If nasal polyps are found, they should also be treated accordingly. Current research is underway regarding new treatment for this, including leukotriene modifiers such as mentelukast and zileuton.
 

More information

For everything you need to know about Asthma, including the symptoms, risk factors, treatments and other useful resources, visit Asthma.

References

1. Eneli I, Sadri K, Camargo C Jr, Barr RG. Acetaminophen and the risk of asthma: The epidemiologic and pathophysiologic evidence. Chest. 2005;127(2):604-12. [Abstract | Full text]
2. Hedman J, Kaprio J, Poussa T, Nieminen MM. Prevalence of asthma, aspirin intolerance, nasal polyposis and chronic obstructive pulmonary disease in a population-based study. Int J Epidemiol. 1999;28(4):717-22. [Abstract | Full text]
3. Kasper L, Sladek K, Duplaga M, et al. Prevalence of asthma with aspirin hypersensitivity in the adult population of Poland. Allergy. 2003;58(10):1064-6. [Abstract | Full text]
4. Szczeklik A, Stevenson DD. Aspirin-induced asthma: Advances in pathogenesis, diagnosis, and management. J Allergy Clin Immunol. 2003;111(5):913-21. [Abstract | Full text]
5. Israel E, Simon RA. Aspirin exacerbated respiratory disease [online]. Waltham, MA: UpToDate; 2005 [cited 17 October 2005]. Available from: URL link
6. Vally H, Taylor ML, Thompson PJ. The prevalence of aspirin intolerant asthma (AIA) in Australian asthmatic patients. Thorax. 2002;57(7):569-74. [Abstract | Full text]