Asthma is a long-term disease that affects the lungs. It causes the lungs' airways to become inflamed and narrowed, making it hard to breathe. According to the National Heart, Lung and Blood Institute, there are more than 22 million people in the United States with asthma, with almost 6 million being children. Asthma is a chronic condition that cannot be cured, and people with asthma usually experience recurring relapses.
Risk Factors
According to MayoClinic.com, there is no clear cause to the increased rate of asthma diagnoses in children. Risk factors include people with a family history of asthma, those exposed to secondhand smoke, people who live in areas of high pollution, infants born with low birth weight, children with a history of lung infections and children who are overweight.
Mechanisms
There are triggers in the environment that can cause asthma, including dust, chemicals from cigarette smoke, air pollution and flowers. Exercise can also trigger asthma, as well as respiratory infections such as colds and sinus infections. When these allergens (particles) are inhaled, the body's immune system identifies them and saves them to memory. The next time that same allergen is inhaled, the body's immune system remembers it, and a reaction takes place that causes the airway to constrict and tighten.
Symptoms
The main symptom of asthma occurs when the airway constricts and breathing becomes difficult. The whistling sound made as the person breathes is known as wheezing. This airway constriction can cause chest pain and tightness. There is increased mucous production in the lungs, which causes congestion and coughing, especially at night, which makes it uncomfortable to sleep. There can be shortness of breath since oxygen is not able to freely enter into the lungs.
Diagnosis
A spirometry test is conducted to check on the status of the patient's airway. The patient is asked to inhale and exhale into a measuring tube known as a spirometer. This is done to check for obstruction in the airway. The ratio of the amount of air exhaled in the first second compared to the total exhaled is recorded. If this ratio is significantly low, this shows evidence of obstruction. In some cases, a chemical substance known as methacholine is given to the patient to inhale. Methacholine causes increased sensitivity in people with asthma, and a positive test rules in asthma.
Treatment
While asthma cannot be cured, the symptoms can be alleviated, and the goal is to help prevent any asthma attacks. Short-term medications such as albuterol and salmeterol, which cause the airway to become relaxed, can be prescribed. These are taken before any form of rigorous activity, as they provide immediate quick relief. Long-term medications are taken to prevent symptoms before they start. Inhaled corticosteriods such as prednisone and beclomethasone work by relieving airway inflammation and swelling. Antileukotriene agents such as zileuton and zafirlukast inhibit the chemical reactions that allow for airway inflammation.
