Asthma is a disease that is characterized by chronic inflammation (swelling) and remodeling (restructuring) of the airways (breathing tubes) and can lead to symptoms of shortness of breath, wheezing (a whistling sound in the chest), chest tightness or coughing.

A common disease affecting 25 million people in the United States (8 percent of the population) and 300 million people worldwide, asthma affects individuals of all ages and races. Asthma is five times more likely to be diagnosed before age 20, although adults of almost any age can develop asthma. Anyone experiencing repeated episodes of cough, wheezing, chest tightness, or breathlessness should be evaluated for asthma.

Causes of Asthma

The exact cause of asthma is unknown, but both genetic and environmental factors are involved. Asthma tends to run in families. Exposure to allergens (i.e., dust mites, mold spores and cockroaches), air pollution, viral infections and tobacco smoke are environmental factors linked to development of asthma. Frequent antibiotic use, obesity, and growing up in an urban environment are lifestyle factors that may also play a role in development of asthma. The critical window for developing asthma seems to extend from before birth to the early years of life, a time when the immune system is developing and airways are growing.

Symptoms of Asthma

The most common asthma symptoms include wheeze, cough with or without phlegm, shortness of breath, and chest tightness. Symptoms range from intermittent/mild to chronic and severe; severity can vary within the same individual at different places and times.

There are also several conditions that that can complicate asthma, including allergic rhinitis, sinusitis, sleep apnea, gastroesophageal reflux, diabetes, and high blood pressure.

Triggers of Asthma Symptoms

The most common triggers of asthma include:

• Weather extremes (hot, cold, humid or abrupt change in weather conditions)
• Exercise (particularly in cold, dry air)
• Strong fumes (car exhaust, tobacco smoke, perfumes, paints, cleaning sprays)
• Allergens (furry pets, dust, mold, grasses, trees, cockroach)
• Strong emotions (laughter, crying)
• Infection (upper respiratory, sinusitis)
• Foods and beverages (nuts, red wine, salad bars with sulfite as a preservative)
• Medications (aspirin, ibuprofen and beta blocker medicines used to treat high blood pressure, migraine headaches and glaucoma)
• Specific jobs that may involve exposures to agents that trigger or worsen asthma such laboratory animals (researchers, lab technicians), flour (bakers), latex (health care workers) and others