Asthma FAQs (cont.)

Asthma Slideshow Pictures

Take the Asthma Quiz!

10 Worst Cities for Asthma Slideshow Pictures

Medical Author:

George Schiffman, MD, FCCP

Dr. Schiffman received his B.S. degree with High Honors in biology from Hobart College in 1976. He then moved to Chicago where he studied biochemistry at the University of Illinois, Chicago Circle. He attended Rush Medical College where he received his M.D. degree in 1982 and was elected to the Alpha Omega Alpha Medical Honor Society. He completed his Internal Medicine internship and residency at the University of California, Irvine.

View Full Profile

Medical Editor:

William C. Shiel Jr., MD, FACP, FACR

Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.

View Full Profile

Who Gets Asthma?

Asthma affects 17.3 million people in the United States (more than 6% of the United States population) and 130 million people worldwide. The number of people affected is eight to 10 times higher in industrialized countries than in developing ones.

Children age 10 and younger account for 50% of asthma cases. In most children, asthma develops before they are 5 years of age, and in more than half, asthma develops before they are 3 years of age.

More than twice as many boys than girls have asthma, although boys are more likely to experience a decrease in symptoms as they reach adolescence. In adult-onset asthma, the number is reversed. Twice as many women than men visit the emergency department and are admitted to the hospital with asthma.

Asthma affects all races worldwide but is more common in blacks and Hispanics, but this may be due to socioeconomic conditions rather than genetics.

Occupational asthma (asthma triggered at work by exposure to irritants present at the workplace) is most common in those who work with animals or animal-derived products and in industries such as plastics, rubber, chemical, textile, electronics, painting, printing, metalworking, baking, and gardening.

Risk factors for asthma include the following:

Smoking or living with a smoker is a major risk factor. About 25% of children who have asthma have at least one parent who smokes.

A family history of asthma: If one parent has asthma, a person has a 25% chance of developing it. If both parents have it, a person has a 50% chance of manifesting asthma.

Having allergies, including hay fever and eczema: It is not known why some people have allergies and some don't, but allergies can be inherited (although people don't necessarily develop the same allergies as their parents have).