Exercise-induced asthma (EIA) and bronchospasm are triggered by exercise in patients with or without chronic asthma. EIA is diagnosed when exercise causes a 15% decrease in lung function and symptoms start after exercise and resolve within 60 minutes. It is common, affecting 10-20% of the general population and up to 90% of asthmatics. Treatment includes warm-up/cool-down periods, medication before exercise like bronchodilators, and ensuring proper asthma management.

1. Fawzia abo ali
Prof.of allergy &clinical immunology
Faculty of medicine
Ain shams university

3. Exercise-induced
asthma & bronchospasm
• Definition: Airway obstruction, and hyper
responsiveness, triggered by exercise
- EIA: exercise induces symptoms of asthma in
patients who have asthma (90% of patients)
- EIB: exercise induces bronchospasm in patients
without chronic asthma, for example, an elite athlete.

4.  physical activity is the second leading cause of airway
constriction after upper respiratory tract infections.
 EIA: symptoms start after exercise, peak 8 to 15 minutes
after exercise and spontaneously resolve in 60 minutes.
 EIA is diagnosed by a 15% decrease in FEV1.
 EIA is most frequently seen in children and young adults
because of their high levels of physical activity.

5. Epidemiology
EIA affects:
90% of asthmatics
40-50% of patients with allergic rhinitis
3-13% of the general population
10-20% of athletes

6. Asthmogenic exercise:
 The type of exercise performed directly affects
the intensity and duration of an EIA episode.
 Asthmogenic sports are characterized by
sustained hyperpnea (deep, rapid breathing
during intense, prolonged aerobic activity)
- basketball
- cycling
- running
- hockey

7. Less asthmogenic sports:
sport that produces intermittent bursts of
hyperpnea, such as baseball, weight lifting
or tennis.
 In addition, activities such as bike-riding
and swimming are less likely to induce EIA
than running.
Swimming appears to be the least
asthmogenic sport, which may in part be
related to the inhalation of humidified air.

8. The sequence of events in EIA is characteristic:
1. Airways dilate during exercise (FEV1 increases by
5% in normal people).
2. When the exercise is over, airway obstruction
begins and progresses until it reaches a peak in 5-10
minutes
3. Spontaneous resolution occurs in 30 minutes.
The tendency toward spontaneous remission is a
hallmark of EIA: one needs only to reverse the acute
event and the patient will then remain free of
symptoms.

10. Pathogenesis
There are 2 theories for EIA pathogenesis:
thermal osmotic
Thermal hypothesis, there is no role for
biochemical mediators.
Osmotic theory has been gaining a wider
acceptance in recent years.

11. histamine, leukotrienes,
prostaglandins

12.  Several studies have noted an increase in the
concentration of cysteinyl leukotrienes (CysLTs) in the
airways of patients with EIB.
 a recent study found that the fraction of exhaled nitric
oxide (FENO) is elevated in asthmatic patients with EIB,
 Angiopoetin 2, a mediator that enhances microvascular
permeability, is increased in the airways in EIB
 Mast cell infiltration of the airways has also been
implicated in EIB.

13. Duration of EIA Symptoms
• Symptoms begin during
or after exercise and
usually worsen 5-20
minutes after stopping
activity
• Some people experience
a “late-phase reaction” 4-
12 hours after exercising.
Symptoms usually less
severe.

14. Diagnosis
 Exercise-induced asthma can be diagnosed by history
only and formal testing is usually required only in
competitive athletes.
 Points in the patient history:
- Onset during or after exercise
- EIB not affect first 5 minutes of exercise
- Symptoms duration longer than 5 minutes

16. Testing for EIA
- FRAST: free running asthma screening test
- Treadmill exercise test
- Cycling
FRAST
A simple screening test in children:
1. Establish a baseline PEF.
2. Have the child run continuously for 7 minutes (same
duration as treadmill exercise test), OR have the child run
until he/she has symptoms.
3. Check PEF, more than 15% decrease in PEF is
diagnostic of EIA.

17. Exercise Challenge Test
Diagnosis:
10 - 15% reduction of PEFR
or FEV1 after 6 minutes
treadmill exercise at 85-
90% maximal heart rate

18. Bronchial provocation tests used to diagnose asthma
in athletes
• Methacholine challenge
• Exercise challenge
• Mannitol inhalation
• Eucapnic voluntary hyperpnea
• Hypertonic saline challenge

19. Management
Non-pharmacological treatment:
- Ensure patient has taken asthma
medicine
• Warm-up and Cool down periods
• Hydrate before, during and after
exercise
• Check pollen and air quality
• Cold Weather
• - breath through the nose

20. Pharmacological treatment
Mnemonic for drugs used for treatment of EIB -
CLIMB:
Cromolyn
Leukotriene receptor antagonist (LTRA),
montelukast
Inhaled steroids (ICS)
Mast cell stabilizers other than cromolyn
Beta-2 agonists, albuterol

23. In conclusion
• EIA is common affecting10-20% of the general
population, and up to 90% of unselected asthmatics
• It is easily managed with warm-up and cool-
down, nasal breathing and pre-medication.
• Cough post exercise best predictor for positive
exercise challenge test
• 90% can be successfully treated with pre exercise
MDI
• Return to play usually safe
• Control of Exercise-induced asthma affords a healthy
lifestyle in which exercise is performed without
restrictions.

24. Resources
• American College of Allergy, Asthma, and Immunology
– http://www.acaai.org
• American College of Chest Physicians
– http://www.chestnet.org
• American Thoracic Society
– http://www.thoracic.org
• The Centers for Disease Control and Prevention
– http://www.cdc.gov/asthma
• National Asthma Education and Prevention Program
– http://www.nhlbi.nih.gov/about/naepp/
• Asthma and Allergy Foundation of America
– http://www.aafa.org
• American Lung Association
– http://www.lungusa.org
• American Academy of Allergy, Asthma, and Immunology
– http://www.aaaai.org
• Allergy and Asthma Network/Mothers of Asthmatics, Inc.
– http://www.aanma.org