New tool for identifying asthma risk in young children

The CHILDhood Asthma Risk Tool (CHART) can determine high asthma risk in pediatric patients aged as young as 3 years, according to a recent study.

In asthma, airflow is limited, leading to wheeze symptoms. Nearly 330 million individuals are afflicted with asthma worldwide, and 1 to 2% of health care budgets in some countries are devoted to asthma. 

Asthma can often lead to hospitalization, being the largest source of hospitalization in young children in Canada, with children aged under 5 years most often affected. While wheezing is a key symptom of asthma and is reported in 30% to 50% of children at least once, it is often not considered evidence of asthma due to many cases experiencing remission by school age.

In recent years, the claim that wheezing is benign has been refuted, as it has been linked to lower lung function and chronic lung disease even after remission. Screening is a reliable method of identifying risk of symptom persistence, leading to treatment, with some tools having been implemented to predict asthma in school-age children.

Current tools have limited application in primary care, requiring invasive testing such as blood or allergy skin prick tests. Other tests are not validated in general populations or have been developed in children predisposed to asthma.

Investigators gathered data from the CHILD study to determine the effectiveness of a symptom-based screening tool in children aged 3 years with high risk of asthma. There were 3224 women and their children participating in the study, until the children turned 5 years of age.

Child questionnaires were given to parents to answer for up to 5 years, multiple times a year. Complete questionnaire and clinic data for children aged 3 and 5 years was also evaluated. CHART was used to categorize asthma and persistent symptoms risk, with risk being categorized in to high, moderate, and low levels, determined by symptoms reported prior to age 3. 

Predictors included use of oral corticosteroids, use of inhaled corticosteroids, use of inhaled bronchodilators, timing and number of wheeze or cough episodes, and emergency department (ED) visits and hospitalizations for asthma or wheeze. 

Children were considered high risk if they had experienced 2 or more episodes of wheezing concurrent with asthma medication, hospitalizations, ED visits, or frequent dry cough. If children had only cough episodes or cough episodes and 1 episode of wheezing, they were considered low risk.

CHART, mAPI, in-study physician diagnosis, and parent-reported external physician diagnosis each independently determined risk of wheeze, asthma, and health care burden in children aged 5 years. Persistent wheeze was determined by 2 or more episodes of wheeze when aged 3 and 5 years. 

Asthma was determined by diagnosis from a pediatric asthma specialist. Use of inhaled or oral corticosteroids, use of bronchodilators, ED visit, or hospitalization for asthma or wheeze determined health care burden.

Wheeze was reported at age 3 in 16.5% of children participating, over half of which had experienced 2 or more episodes. Of the 220 children with 2 or more episodes, 77.7% had used asthma medication. An asthma diagnosis had been assigned to 10% of the entire study population by age 3.

At age 3, high risk of asthma was defined in 7.1% of participants, moderate risk in 23.8%, and low risk in 69.1%. Asthma was deemed definite in 5.6% of children, possible in 6.7%, and diagnosed from an external physician in 4.5%.

Bronchodilators were used by 9.8% of children and corticosteroids by 11% Children required an ED visit or hospitalization in 3.5% of cases.

At age 5, 35.9% of children who had 2 or more wheeze episodes at age 3 still had wheeze symptoms. Diagnosis of wheeze and asthma were successfully determined by CHART more often than by physicians. The results validated CHART for diagnosing risk of wheeze and asthma development in young children.

Reference

Reyna ME, Dai R, Tran MM, Breton V, Medeleanu M, Lou WYW, et al. Development of a symptom-based tool for screening of children at high risk of preschool asthma. JAMA Netw Open. 2022;5(10):e2234714. doi:10.1001/jamanetworkopen.2022.34714