Noninvasive tool identifies children aged as young as 3 years at high risk for asthma
Click Here to Manage Email Alerts
A noninvasive and validated symptom-based screening tool identified children who were at high risk for asthma as early as age 3 years, according to a study published in JAMA Network Open.
Primary care settings may incorporate the tool to trigger timely treatment initiatives and promote active disease monitoring, the researchers said.
“Health care practitioners do not have any easy way to identify children at risk of chronic symptoms in the preschool period, even though most adults with asthma report that their symptoms began at that age,” Myrtha E. Reyna-Vargas, MSc, biostatistician, and Padmaja Subbarao, MD, MSc, clinician-scientist, both with the department of pediatrics at the Hospital for Sick Children in Toronto, told Healio in a statement.
“We wanted to simplify the identification of kids at risk at primary care so that physicians can evaluate these children and start treatments earlier,” they said.
The CHILDhood Asthma Risk Tool (CHART) uses the timing and number of wheeze or cough episodes, use of asthma medications, and ED visits or hospitalizations at age 3 years to identify children at high, moderate or low risk for asthma or persistent symptoms at age 5 years.
The study involved 2,511 children (mean age, 3.08 years; standard deviation, 0.17; 52.7% boys; 64.9% white) who participated in a 3-year clinic visit between Jan. 1, 2008, and Dec. 31, 2012, including 2,354 (93.7%) who had available outcome data at age 5 years.
At age 3 years, 16.5% of the children had reported wheeze, of whom 53.1% experienced two or more episodes and 77.7% were using an asthma medication, and 10% overall were diagnosed with asthma.
Study results
At age 3 years, CHART classified 178 (7.1%) children as high risk for asthma, 597 (23.8%) at moderate risk and 1,736 (69.1%) at low risk, including 57 children deemed high risk that physicians had not identified.
Seventy-nine (35.9%) of the 220 children who had experienced two or more episodes of wheeze at age 3 years continued to experience wheeze at age 5 years. Of them, CHART classified 72 (91.1%) as high risk (area under the receiving operator curve [AUROC], 0.94; 95% CI, 0.9-0.97), compared with 49 (62%) classified as high risk by in-study physicians (AUROC, 0.79; 95% CI, 0.74-0.85), which included four that CHART had missed, and 33 (48.5%) by the modified version of the Asthma Predictive Index (mAPI; AUROC, 0.74; 95% CI, 0.68-0.8), including one that CHART had missed.
Sensitivity for detecting true-positive asthma at age 5 years based on symptoms from age 3 years ranged from 50% for CHART (AUROC, 0.73; 95% CI, 0.69-0.77), to 43.5% for in-study physicians (AUROC, 0.77; 95% CI, 0.73-0.81), 41.7% for parental reports of external physician-diagnosed asthma, and 24.4% for mAPI (AUROC, = 0.62; 95% CI, 0.568-0.65).
Of the 367 children reporting current asthma medication use or ED visits or hospitalizations at age 3 years, CHART classified 178 (48.5%) as high risk, with recommendations for a follow-up assessment 6 to 12 months later for the rest. CHART had the highest sensitivity for predicting health care use at age 5 years (45.5%; AUROC, 0.7; 95% CI, 0.61-0.78), followed by standardized mAPI (25%), in-study physicians (36.4%) and external physician diagnosis (34.4%).
Researchers noted that CHART continued to have higher sensitivity and AUROC compared with skin prick test data, and blood eosinophilic levels recorded at age 1 year did not improve CHART’s performance in diagnosing asthma or persistent wheeze.
Analyses using external cohorts showed CHART also produced similar results for predicting persistent wheeze among 2,185 children aged 5 years drawn from a general population included the Raine Study (AUROC, 0.82; 95% CI, 0.79-0.86), and among 349 high-risk children aged 7 years in the Canadian Asthma Primary Prevention Study (AUROC, 0.87; 95% CI, 0.8-0.94).
CHART performance
“We were surprised that this simple tool outperformed other common diagnosis tools for identifying children who were at high risk for ongoing symptoms of asthma,” Reyna-Vargas and Subbarao said.
Noting that CHART relies on information that health care providers can gather easily through interviews and parent-reported questionnaires in primary care and low-resource settings, the researchers said their tool performed as well as or better in identifying children at high risk for asthma than other testing, including methods requiring more invasive measures.
“Doctors need simple, standardized approaches for flagging children at high risk for asthma. Tools like CHART are ideal because parents can directly record symptoms every 6 months, helping busy clinicians so they can focus on in-depth follow-up on this smaller group of patients,” Reyna-Vargas and Subbarao said.
With improved identification and routine use of the tool, the researchers continued, providers could promote timely treatment control, improve quality of life and reduce the clinical and economic burden of asthma.
Meanwhile, the researchers intend to continue their work.
“We need to test the use of this tool in a real-world practice setting and evaluate its performance to see if it matches the cohort observational studies,” Rayna-Vargas and Subbarao said.
For more information:
Myrtha E. Reyna-Vargas, MSc, and Padmaja Subbarao, MD, MSc, can be reached at Department of Pediatrics, The Hospital for Sick Children, 555 University Ave., Toronto, Ontario, Canada M5G1X8.