Swern AS, Tozzi CA, Knorr A, Bisgaard H. Ann Allergy Asthma Immunol. 2008;101(6):626–630
PURPOSE OF THE STUDY. To identify symptoms and other factors that may be predictive of an asthma exacerbation in children 2 to 5 years of age.
STUDY POPULATION. Children 2 to 5 years of age who participated in a previous, double-blind, randomized, multicenter, parallel-group, placebo-controlled, 12-week study of 4 mg of monteleukast for the treatment of persistent asthma.
METHODS. A posthoc analysis was performed with data collected on 689 patients. Caregivers provided twice-daily answers in a validated, asthma-specific, diary record of daytime symptoms (cough, wheeze, difficulty breathing, and activity limitation), nighttime cough symptoms, β2-adrenergic receptor agonist use, and medical visits for worsening asthma. Scoring for daytime symptoms used a 6-point scale from 0 (no symptoms or limitations) through 5 (very severe symptoms or limitation) and scoring for nighttime cough used a 5-point scale from 0 (no nighttime cough) through 4 (coughed all night and disturbed the caregiver's sleep). To identify predictors of an exacerbation (worsening symptoms that led to oral corticosteroid use, an unscheduled visit to a physician or emergency department, or hospitalization), information was analyzed by using general estimating equations with an exchangeable, within-subject, logarithmic odds ratio regression structure.
RESULTS. A total of 196 (28%) of the 689 patients enrolled had ≥1 asthma exacerbation during the study period, and 235 exacerbations occurred overall. Each of the diary symptoms and β2-adrenergic receptor agonist use increased significantly, but at different rates, before an exacerbation. Only the combination of wheeze, daytime cough, and β2-adrenergic receptor agonist use were predictive of an exacerbation. Overall, 149 (66.8%) of 223 exacerbations were predicted correctly 1 day before the exacerbation. The false-positive rate was 14.2%.
CONCLUSIONS. An imminent asthma exacerbation was predicted by a combination of increased cough, wheeze, and β2-adrenergic receptor agonist use at night, although individual symptoms were not predictive.
REVIEWER COMMENTS. If earlier prediction of asthma exacerbations were possible, then earlier treatment and decreased severity and utilization of health care resources might result. This study provides some evidence that early prediction is possible. However, the study is limited by the lack of a standard definition for an asthma exacerbation in young children and the lack of access to some outcome measures, such as unscheduled visits and hospitalization exacerbation. The ability to predict exacerbations remains to be proved. Parental education is imperative in predicting exacerbations in young children.
- Copyright © 2009 by the American Academy of Pediatrics