Asthma is a chronic lung disorder that causes swelling and inflammation in the lungs. According to the Centers for Disease Control and Prevention (CDC), asthma affects more than 25 million people in the United States, or about 8 percent of the population.

Asthma and its symptoms can appear at any point in time. You can develop it later in life even if you have no history of asthma in your childhood.

Adult-onset asthma may suddenly occur because of a combination of factors.

One common reason for adult asthma is constant exposure to an allergen. Allergens are substances that can cause an immune reaction in people who are sensitive to them. Examples include mold and dust mites. Allergies are the trigger for many cases of adult-onset asthma.

Depending on your occupation, you may be exposed to asthma triggers at work. According to the CDC, about 17 percent of adult asthma cases are work-related. Work-related asthma is more likely to be severe, with periods of worsening or more frequent symptoms — also called asthma attacks.

The exact causes of asthma can be difficult to pinpoint.

Allergies and triggers in the environment can cause asthma symptoms or an asthma flare-up. Genetics can also play a role.

According to the Asthma and Allergy Foundation of America (AAFA), people who are pregnant may develop asthma symptoms during their pregnancy or after giving birth. Sometimes, people who have never had symptoms before experience asthma during menopause.

Ultimately, the exact reasons why people develop asthma remain unclear.

Different people have different triggers. Here are some common triggers that may cause an asthma attack:

  • smoke
  • mold and mildew
  • air pollution
  • feather bedding
  • dust mites
  • cockroaches
  • animal dander or saliva
  • respiratory infections or colds
  • cold temperatures
  • dry air
  • emotional stress or excitement
  • exercise

Asthma causes inflammation and narrowing in the airways. Narrowed airways cause chest tightness and difficulty breathing. Symptoms of adult-onset asthma include:

Untreated asthma may affect your daily activities. Shortness of breath, for example, can sometimes make physical activity uncomfortable or difficult.

If you suspect your symptoms are due to asthma, consider making an appointment with a doctor to discuss treatment options.

There are quick-relief and long-term control medications for adults with asthma. Most adults with asthma use a combination of these medications to treat their asthma.

Quick-relief medications are designed to ease symptoms caused by an asthma attack or flare-up.

Long-term control medications are designed to reduce inflammation and swelling over longer periods of time. This is intended to prevent asthma attacks and long-term airway damage caused when asthma is not well managed. Long-term control medications are typically taken daily for months, or even years.

Create an asthma action plan

The American Lung Association recommends creating an asthma action plan to outline what type of medication you should take and when. It should also provide details about what to do if your asthma is dangerously out of control. These instructions will help you, friends, and relatives know when it’s time to change treatments or seek emergency care.

To make this plan:

  • Discuss treatment options with your doctor.
  • Plan what you should do in the event of an asthma flare-up.
  • List what triggers can be avoided and the best ways to avoid them.
  • Define at what point you need to increase treatment measures to prevent or reduce the severity of an attack.

Share this plan with friends, relatives, and any caregivers you may have. Together, you should be able to successfully treat your asthma and avoid future complications.

Children with allergies may not experience asthma from exposure to allergens when they’re younger. Yet over time, their bodies can change and react differently. This can lead to adult-onset asthma.

Childhood asthma and adult-onset asthma have the same symptoms, and both have similar treatments. However, each comes with different challenges.

Children

Children diagnosed with asthma are more likely to have intermittent symptoms — symptoms that come and go — though some children do have daily symptoms. Allergens can set off an asthma attack. Children are typically more sensitive to allergens and more prone to asthma attacks. This is because their bodies are still developing.

Children diagnosed with asthma may find that their symptoms ease or almost completely disappear during puberty, but they may return later in life.

The American Lung Association also describes secondhand smoke as particularly dangerous for children. An estimated 400,000 to 1 million children with asthma have their condition worsened by secondhand smoke.

The CDC states that 1 in 6 children with asthma visit the ER each year, and 1 in 20 cases are hospitalized because of asthma.

Adults

With adults, symptoms are typically persistent. Daily treatment is often required to keep asthma symptoms and flare-ups well managed.

According to the AAFA, allergies trigger at least 30 percent of adult asthma cases. This 2018 study suggests that obesity increases the risk of developing adult-onset asthma.

Death resulting from an asthma attack is rare and mainly occurs in adults over age 65, according to the CDC. However, it is important to take symptoms and treatment for those symptoms seriously, no matter your age.

Asthma is a common disorder among adults. Although it can lead to difficulty breathing, with proper planning and preparation it’s possible to manage the symptoms and prevent frequent asthma attacks.

There are many medications available for both short- and long-term care. It’s useful to create a plan detailing how to prevent an attack and when to seek emergency care. Share your plan with friends, relatives, and any caregivers you may have.

Many people, including athletes, live with asthma and lead very healthy lives. They’re able to do this, in part, because they know how to manage their asthma. Be sure to work with your doctor so you have a treatment plan that is right for you.