Asthma, << AZ muh, >> is a lung disease characterized by breathlessness, wheezing, and coughing. People with asthma suffer from inflammation of the bronchi (airways to the lungs). The inflamed airways react to irritation by swelling, constricting, and filling with mucus. These changes obstruct airflow (the ability to force air in and out of the lungs). An asthmatic person may feel short of breath or have difficulty breathing. Severe attacks may involve spasms (sudden constriction) of the airways. Sufferers gasp for air and feel that they are suffocating. These attacks require immediate medical attention and can cause death.
A variety of environmental conditions, called triggers, may irritate the sensitive airways of asthma sufferers and cause an attack. Triggers include pollen, mold spores, chemical irritants, tobacco smoke, animal dandruff, and dust mites. Other triggers include respiratory infections, exercise, or breathing cold air. An attack usually begins within minutes after exposure to a trigger. The symptoms can last a few minutes, several hours, or even days.
Physicians diagnose asthma by studying the patient’s history of symptoms. They also perform a physical examination and tests of lung function. Recurring episodes of breathlessness caused by one or more triggers usually indicate asthma. Physicians use a device called a spirometer to determine the amount of air patients can breathe out of their lungs. Another device called a peak flow meter measures airflow. People with asthma often have reduced airflow when exposed to triggering substances, or after vigorous exercise.
Asthma affects both children and adults. Some children with asthma have fewer symptoms as they get older. Others develop more symptoms. Despite advances in the treatment of asthma, the incidence of the disease is increasing, especially among children in cities.
Causes.
Scientists are not certain what causes asthma or why it is becoming more common. Research shows that infants exposed to indoor air pollution, especially tobacco smoke, have a much higher risk of developing asthma than infants who are not exposed.
Asthma tends to run in families. It is often accompanied by allergies. People with asthma, or members of their family, often have respiratory allergies, such as hay fever. In addition, they may be allergic to certain foods. Asthmatic persons and their family members also have a higher incidence of an allergy called atopic eczema. This condition causes itchy red swellings on the skin. Researchers are working to discover genetic markers that can identify people at risk of developing asthma.
Treatment.
There is currently no cure for asthma. However, the disease can be controlled. Sudden attacks can be prevented by avoiding the substances that trigger them. But it is not possible to avoid all asthma triggers all the time, so asthma sufferers usually require medication.
Medications are divided between those used for quick relief from sudden attacks, and others used for long-term control of asthma symptoms. Quick-relief medicines are usually bronchodilators. These drugs decrease the constriction in the airways by relaxing small muscles in and around the lungs. These medicines are inhaled from small aerosol canisters at the onset of a sudden asthma attack. Long-term control medications include corticosteroids. Corticosteroids are anti-inflammatories (substances that reduce inflammation) that can be inhaled or taken by mouth.
Most people with asthma can lead normal, even active, lives. With proper treatment, people with asthma can participate in sports. They can even play sports that require intensive breathing, such as football, track and field, or swimming.
