Asthma is a chronic lung disease that causes inflammation and narrowing of the airways. Asthma symptoms include wheezing, coughing, chest tightness, and shortness of breath. Asthma can develop at any age, but it most commonly starts in childhood.
When does asthma develop in children?
The majority of asthma cases begin early in life. According to the Centers for Disease Control and Prevention (CDC), asthma affects around 6 million children in the United States. Asthma is one of the most common chronic conditions in childhood.
Asthma can develop at any age, but it most often starts before age 5. According to the Asthma and Allergy Foundation of America:
- Over 80% of children who develop asthma do so before age 5.
- The average age of asthma onset is around 3 years old.
- Boys are more likely to develop asthma before age 5 than girls.
- Asthma rates peak between ages 1 and 3.
While asthma can arise at any time during childhood, the first signs and symptoms generally appear during the first 5 years of life. Let’s take a closer look at when asthma emerges at different ages.
Asthma in infants
Asthma can occasionally develop in infants under 1 year old. According to one study, around 2-3% of infants develop asthma symptoms before their first birthday. Some of the early signs of asthma in infants include:
- Wheezing or whistling sound when breathing
- Coughing, especially at night
- Rapid breathing
- Difficulty feeding due to breathing difficulties
- Tightness in the chest
Wheezing is a common symptom of asthma in infants. Parents may notice wheezing or a high-pitched whistling sound when their baby breathes out. The wheezing is caused by narrowed airways in the lungs. However, not all wheezing or coughing indicates asthma in young infants. Other respiratory infections can cause similar symptoms. If an infant shows signs of asthma, it’s important to see a doctor to confirm the diagnosis.
Asthma in 1-5 year olds
The majority of asthma cases first develop between ages 1 and 5. According to the AAAAI, asthma begins more frequently in pre-school aged children than any other age group. About half of all children who get asthma develop symptoms before turning 3 years old.
Some early symptoms of asthma in 1-5 year olds include:
- Frequent cough, especially at night
- Wheezing after exercise or play
- Breathing problems such as fast breathing or shortness of breath
- Complaints of chest tightness or chest pain
- Getting tired easily during physical activity
In preschoolers, asthma symptoms often worsen at night or with exercise, play, laughing, or crying. The symptoms may come and go over weeks. Asthma episodes can be triggered by viral infections, tobacco smoke, pet dander, cold air, or other irritants. Mild asthma symptoms are more common in children ages 1 to 5. Moderate or severe asthma is less likely to develop for the first time in this age group.
Asthma in older children
Asthma can arise after age 5, although this is less common. According to the AAAAI, about 20-30% of children develop asthma between the ages of 6 and 14. The symptoms of asthma generally look similar in older children as in younger kids. However, asthma that starts later in childhood is more likely to be moderate or severe. Some signs of asthma developing after age 5 include:
- Chronic cough, especially at night
- Wheezing or whistling sound when exhaling
- Shortness of breath and chest tightness
- Coughing, wheezing, or difficulty breathing with exercise
- Fatigue or reduced ability to exercise
In school-aged children over 5 years old, asthma symptoms may be worse with physical activity or exercise. Older kids are also better able to describe how they feel when experiencing asthma symptoms. They may complain of chest tightness, breathing difficulties, or fatigue during sports. Asthma can still develop in the teen years, although this is relatively uncommon. Teenagers who develop new asthma symptoms should see a doctor.
Asthma rates by age
Asthma prevalence increases rapidly in early childhood, peaks around ages 5-10, and then declines in the teenage years. Here is an overview of asthma rates by age group among U.S. children:
- Ages 0-4: 8.2% of children have asthma
- Ages 5-10: 10.1% of children have asthma
- Ages 11-17: 8.0% of children have asthma
Asthma rates are highest between ages 5 and 10, lower in young adults, and increase again in maturity. Although asthma often persists from childhood into adulthood, some children do appear to “outgrow” their asthma. By the teen years, asthma seems to resolve in around 20% of cases.
Asthma incidence by age
Asthma incidence refers to the rate of new cases in a population over time. Incidence shows how many people are newly diagnosed with asthma each year. The numbers below reflect how many out of 10,000 children are newly diagnosed with asthma per year in different age groups:
- Ages 0-4: 67 cases per 10,000 children per year
- Ages 5-10: 35 cases per 10,000 children per year
- Ages 11-17: 18 cases per 10,000 children per year
Asthma incidence peaks between ages 1 and 3, with over 100 cases per 10,000 children per year. After preschool ages, the rate of new asthma diagnosis drops but remains substantial until the late teen years.
Risk factors for childhood asthma
Certain factors can increase a child’s risk of developing asthma. Some of the main risk factors include:
- Family history. Children with one or more asthmatic parents are more likely to develop asthma.
- Allergies. Children with other allergic conditions like eczema, hay fever, or food allergies are at higher risk.
- Premature birth. Babies born prematurely have an increased risk of asthma.
- Smoking. Exposure to tobacco smoke can trigger asthma in young children.
- Respiratory infections. Severe respiratory viral infections early in life may increase susceptibility.
Knowing these risk factors can help parents and doctors identify children who may be more likely to develop asthma symptoms. Taking preventive measures to control asthma triggers may help reduce asthma onset in at-risk children.
Diagnosing asthma in children
Since asthma symptoms can overlap with other respiratory conditions in kids, it’s important to see a doctor for an official diagnosis. A pediatrician will take a full medical history and do a physical exam when asthma is suspected.
Diagnostic tests used to confirm asthma in children may include:
- Lung function tests to measure airflow and lung volume
- Allergy testing to identify potential allergy triggers
- Chest x-ray to rule out other lung conditions
- Spirometry to assess lung function
Lung function tests and spirometry are the main methods used to diagnose asthma in most children over age 5. These non-invasive breathing tests check for obstruction in the airways, a key sign of asthma. Allergy tests also help distinguish asthma from allergies.
Asthma symptoms in children
The signs and symptoms of asthma in children include:
- Wheezing – high-pitched whistling sound when breathing out
- Coughing, especially at night
- Shortness of breath
- Chest tightness or chest pain
- Reduced ability to exercise or play
- Fatigue or low energy
In infants and babies, it can be harder to identify asthma symptoms. Early signs in infants may include wheezing, coughing, troubled feeding, and breathing problems. Asthma symptoms in young children tend to come and go and are often worse at night or during/after physical activity. Symptoms may flare up in response to asthma triggers like colds, allergens, weather changes, and air irritants.
Mild vs. severe asthma in children
The severity of asthma symptoms can vary widely from child to child. Asthma is classified as mild, moderate or severe based on symptom frequency and intensity:
- Mild intermittent asthma – Brief episodes of symptoms up to twice per week with no symptoms between flare-ups.
- Mild persistent asthma – Symptoms more than twice weekly but less than once daily. Nighttime symptoms up to twice per month.
- Moderate persistent asthma – Daily symptoms with nighttime flare-ups more than twice per month.
- Severe persistent asthma – Frequent symptoms both day and night. Severe attacks affect activities and sleep.
Younger children under 5 years old more often experience mild intermittent or persistent asthma. Severe asthma symptoms are more likely to arise later in childhood or in the teen years. Prompt treatment can help control symptoms and prevent asthma from worsening over time.
Childhood asthma treatment
While there is no cure for asthma, symptoms can be well-controlled with proper treatment. The main medical treatments for asthma in children include:
- Inhaled corticosteroids – These anti-inflammatory drugs are the most effective long-term control medication for persistent asthma.
- Leukotriene modifiers – These oral medications help prevent airway inflammation.
- Bronchodilators – Quick-relief inhalers like albuterol relax airway muscles to ease breathing.
- Biologic therapies – Monoclonal antibodies can target specific proteins involved in asthma.
Doctors also recommend avoiding asthma triggers whenever possible. Kids with asthma may benefit from allergy testing and immunotherapy. Asthma action plans outline medications and guidance for keeping symptoms under control day-to-day and during exacerbations. With appropriate management, most kids with asthma can live a full, active life.
Does asthma go away with age?
Asthma starting in childhood often continues into adulthood. About half of children with asthma still have symptoms as an adult. However, some children appear to “outgrow” their asthma. Studies suggest around 20-60% of kids with asthma go into long-term remission by early adulthood.
Children are more likely to outgrow asthma if:
- Asthma symptoms are mild
- They have minimal to no allergies
- They have no other allergic conditions
- Asthma developed after age 3
- Their asthma improved by the teen years
Even if symptoms resolve, asthma can recur later in life after a period of remission. Doctors are still uncertain why some children seem to outgrow their asthma. For most kids, asthma is a lifelong condition requiring long-term monitoring and treatment.
Preventing asthma in children
While asthma can’t always be prevented, certain protective measures may lower kids’ risk. Some tips for reducing asthma onset include:
- Breastfeeding babies for at least 4-6 months
- Avoiding tobacco smoke exposure
- Prompt treatment of respiratory infections
- Identifying and avoiding allergy triggers
- Controlling indoor humidity levels
- Giving supplements like vitamin D
For children at high risk due to family history, doctors may recommend preventive asthma medications. Early intervention before symptoms appear may help stop asthma from fully developing in some cases.
The takeaway
Asthma most often arises in early childhood, especially before age 5. The peak ages for developing asthma are between 1 and 5 years old. While asthma can start at any age, about 80% of cases develop in children under age 5. Asthma incidence declines after the preschool years but remains significant through adolescence. The typical signs of asthma like coughing, wheezing, and breathing difficulty generally emerge in the first years of life. Prompt diagnosis and treatment are key to reducing asthma exacerbations and severity. With proper management, most children with asthma can live normal, active lives.
