Some people develop asthma as adults. This type of asthma tends to be more severe than childhood-onset asthma.1 People with adult-onset asthma are more likely to have frequent asthma attacks.2 Their lung function declines more quickly than people with other types of asthma.1 People with this asthma subtype usually have high levels of eosinophils, a type of white blood cell that increases when there is inflammation.
Unlike most people with childhood-onset asthma, people with adult-onset asthma do not usually have other allergic diseases.3 Women are more likely than men to have adult-onset asthma.1 The risk is also greater for people who are very overweight.
Interestingly, for many people, adult-onset asthma may actually have its roots in childhood. A study from Arizona showed that nearly two-thirds of people who were “newly diagnosed” with asthma at age 22 years wheezed before age 3 years.4
What causes adult-onset asthma?
Adult-onset asthma does not run in families the way childhood asthma does. Instead, many factors have been linked to asthma in adulthood.
Certain types of work
Asthma that starts or worsens on the job is one type of adult-onset asthma.5 Usually, a chemical or allergen used at the job site is responsible for triggering symptoms. The symptoms often get better during weekends, holidays, or time away from work.
Smoking increases the risk of asthma. Smokers with hay fever are at particularly high risk. Compared with people who do not smoke, their risk of developing asthma is:6
- 2 times higher for people with 1-10 pack-years
- 3.7 times higher for people with 11-20 pack-years
- 5 times higher for people with 21+ pack-years
Pack-years are calculated as the packs smoked per day times the number of years as a smoker.
Respiratory infections and nasal congestion
Researchers are not sure how infections cause asthma, but the link has been clear for decades. The infections may injure the airways, which leads to ongoing inflammation. They may also make the airways sensitive to outside triggers.1 People with non-allergic nasal congestion (rhinitis) are more likely to have adult-onset asthma, although the reasons for this are also unclear.
Women are more likely than men to develop asthma in adulthood.1 Some research suggests that there is a link between female hormones and asthma, but nothing has been proven.
Stressful life events
Adults who experience high levels of stress are at a higher risk of developing asthma.1 Illness in the family, marital problems, divorce or separation, and work-related stress are strongly linked with asthma. One theory is that stress affects the immune system in ways that lead to asthma.
How is it diagnosed?
Asthma is diagnosed based on symptoms, physical examination, and lung function tests.7
A test called spirometry may be performed to see how much and how quickly you can exhale air. For many people with adult-onset asthma, air has a very hard time getting in and out of the lungs.1 Medications called bronchodilators can sometimes be used to open up the airways. For people with adult-onset asthma, these medications do not work as well as expected.8
How is adult-onset asthma treated?
The first step to treating asthma is to avoid known triggers, if you can. If you are exposed to a chemical or allergen at work, see if it is possible to protect yourself.1 If you smoke, try to quit.
Treatment for adults with asthma follows the steps for long-term asthma management. Adult-onset asthma is often severe, and people with it may need higher doses of inhaled corticosteroids. For some adults with asthma, inhaled corticosteroids are not very effective.3 In this case, oral corticosteroids may be necessary.2 Your health care provider may suggest additional tests to figure out what type of asthma you have. The results can help with treatment selection.
Wheezing and breathlessness may be symptoms of obesity as well as asthma. If you are very overweight and your provider suspects you have asthma, lung function tests may be done to determine which condition is causing symptoms. If the symptoms are caused by asthma, they may improve with weight loss.3 Symptoms improve with as little as 5% to 10% weight loss. Dramatic improvements have been seen after bariatric surgery.1,3
Will adult-onset asthma go away?
Most of the time, adult-onset asthma does not go away. One study showed that 95% of people diagnosed with adult-onset asthma still had asthma five years later.10
Do you have adult-onset asthma?