7 Things You Should Know About Adult-Onset Asthma

Updated: Jun. 30, 2021

While more common in children, asthma can appear at any time in life—and adult-onset asthma can be dangerous if left untreated.

What is adult-onset asthma?

Asthma is a chronic respiratory disease that causes inflammation in the airways in the lungs. This swelling can make it difficult for people to breathe, especially when exposed to something that triggers their asthma, like an allergen, exercise, or cold weather.

It’s one of the most common diseases among children, according to the American Lung Association (ALA.) But asthma symptoms can occur at any time in life—and it affects about one in 12 adults in the United States.

There are three likely explanations for having asthma as an adult:

  • A case of well-controlled childhood asthma re-emerges later in life.
  • You had asthma as a kid but never received a diagnosis.
  • You’re experiencing asthma symptoms for the first time during adulthood.

This adult-onset (or late-onset) asthma is not well-understood.

But research from European Respiratory Review shows that it’s often more severe and can lead to a faster decline in lung function.

That’s why doctors say it’s important to recognize the signs of asthma in adulthood so there’s no delay in treatment. Here’s what they want you to know about this potentially dangerous respiratory disease.

It’s different from childhood asthma

Doctors don’t know exactly why some people develop asthma as an adult, says Sumita Khatri, MD, an adult pulmonary and ICU physician and member of the Asthma and Allergy Foundation of America’s Medical Scientific Council.

She says that while childhood asthma is much more likely to be allergy related, adult-onset asthma often develops from separate processes.

“Sometimes there is a family history of asthma and it lays quiet until adulthood,” Dr. Khatri explains. Environmental factors can then trigger its onset. They could include:

  • Exposure to workplace irritants
  • Air pollution and smoking (or exposure to secondhand smoke)
  • Hormonal changes as we age
  • Progression from other conditions, like a virus or sinus disease

She says even if adults have a mild genetic predisposition to asthma, they might be more likely to develop the disease in a higher-risk environment, such as living near a high-traffic area or having occupational exposure to certain chemicals.

Still, the European Respiratory Review says a genetic link is less evident in adult-onset asthma than among childhood cases. Medical professionals’ current understanding suggests there may be additional risk factors at play.

Some people may be more at risk

Obesity has been linked to both increased incidence of adult-onset asthma and increased severity of asthma [symptoms],” says Kirsten Kloepfer, MD, an assistant professor at Indiana University specializing in asthma and allergies.

It’s also the most common asthma comorbidity, according to a review published in Asthma Research and Practice. Of American adults with asthma, approximately 38 percent are also obese. But obesity isn’t just a risk factor for developing asthma—it also can reduce the effectiveness of asthma treatment.

Dr. Kloepfer says hormone fluctuations during pregnancy and menopause can trigger asthma in adults as well—so, being a woman increases your risk. While this link is not well-understood, the study in European Respiratory Review notes that in adults over age 35, asthma is 20 percent more frequent in women than in men.

High stress levels are also increasingly recognized as an adult asthma risk factor. A study from the Journal of Asthma suggests people with very or extremely stressful jobs are twice as likely to develop adult-onset asthma.

This is because stress heightens the immune system response to asthma triggers, explains Jennifer Monroy, MD, a Washington University allergist and immunologist with Barnes-Jewish Hospital in Saint Louis, Missouri.

This reaction reduces a person’s threshold—or sensitivity—for having asthma symptoms triggered.

The symptoms may mimic other diseases

Adults with asthma typically have similar symptoms to children with the disease, like coughing, wheezing, chest tightness, and shortness of breath.

But adults are more likely to experience other symptoms, including:

  • Difficulty breathing during exercise
  • Insomnia
  • Chronic fatigue and brain fog

These asthma symptoms in adults can easily be mistaken for other health issues, Dr. Khatri says.

For example, some patients report having bronchitis symptoms every spring and fall, she says, when their condition may actually be asthma flare-ups.

Along with infections like bronchitis, adult asthma symptoms can mirror those associated with chronic obstructive pulmonary disease (COPD,) gastroesophageal reflux disease (GERD,) diabetes, and heart disease.

Man in medical consultation discusses with his doctor using a puffer inhaler for asthmaFly View Productions/Getty Images

It’s underdiagnosed

Because adult asthma can mimic other conditions and infections, its diagnosis and treatment often get delayed, Dr. Khatri explains.

But there’s also the issue of perception. Unless people are experiencing a drastic change in lung function, they may not even notice asthma symptoms as an adult.

“Some people are able to compensate and soldier through episodes and symptoms, or not even perceive how severe they are,” Dr. Khatri says.

There’s also a misconception that asthma exclusively starts in childhood, she says, so people often think if they didn’t have symptoms as a child, their adult symptoms must be something else.

It’s a dangerous health condition

“The mortality rate is higher in adults than children due to adults ignoring their symptoms and not seeking appropriate treatment,” Dr. Kloepfer says.

According to the Centers for Disease Control and Prevention (CDC), adults are nearly five times more likely to die from asthma than children.

Frequent symptoms can significantly interfere with someone’s quality of life, Dr. Khatri says.

Repeated episodes also perpetuate airway inflammation. This leads to increasingly severe symptoms that become harder to control and treat—and can result in permanent loss of lung function, an effect called airway remodeling.

It can be more difficult to treat

According to Dr. Khatri, there are multiple paths through which adult-onset asthma appears to develop, and each person can have a very different type of asthma. This variation makes adult-onset asthma more challenging to treat.

Yet there are physiological barriers to effective asthma treatment in adults as well.

“As we age, our muscles become stiffer,” Dr. Kloepfer says. “The muscles that we use to take deep breaths are weaker in adults, making it more difficult to breathe deeply, especially in an older person with asthma.”

Research from Clinical Interventions in Aging shows our airway receptors also undergo structural changes over time that make them less likely to respond to medications.

Effective treatment can be even more complicated for adults with underlying health issues. For example, Dr. Kloepfer says obesity is linked to other conditions—like GERD and obstructive sleep apnea—that have been shown to worsen asthma.

“If an adult is taking a beta-blocker for a heart problem or hypertension, their asthma can be more difficult to control,” she adds.

Asthma treatment can also cause more side effects in adults than in children. Adults with severe or difficult-to-treat asthma may need to rely on strong oral corticosteroids to manage their symptoms.

While generally effective, long-term use of these medications can contribute to health issues like osteoporosis, glaucoma, and cataracts, Dr. Kloepfer says.

Adult-onset asthma is manageable

Dr. Khatri says researchers continue to work toward developing more effective adult-onset asthma therapies. Still, outcomes significantly improve when there’s less delay in medical treatment.

That’s because early detection allows for swift intervention with a personalized asthma action plan. This is a custom strategy someone develops with a doctor to manage asthma, reducing its impact on quality of life.

An asthma action plan dictates how and when to take medications and what to do when symptoms worsen, for example. But it also helps advise people with asthma on lifestyle changes that contribute to better asthma control, such as diet, exercise, smoking cessation, lung-capacity monitoring, and trigger avoidance.