This study observed children with chronic nonspecific isolated cough (NIC) to investigate clinical differences between children whose symptoms resolved spontaneously and those who eventually developed asthma and then explored the differences among the children who eventually developed asthma in terms of their time of response to a trial of inhaled corticosteroid (ICS).
Children with chronic NIC were managed either with a wait-and-review approach or with a 2-week trial with 400 μg/d inhaled budesonide according to the preference of their parents. Responses were monitored with a validated cough score. Treatment was prolonged to 8 weeks in the case of partial responders. All children were followed up at 3-month intervals.
A total of 109 children (median [interquartile range] age, 5 [3.5-9] years; cough duration, [8-16] weeks]) were followed for a mean (± SD) time of 21(± 5) months. Cough did not recur in 71% (spontaneous resolution) but relapsed in 28% of the children who later responded to ICS treatment again (asthma). Aeroallergen sensitization (relative risk, 2.86; 95% CI, 1.17-6.99) and previous history of chronic cough (relative risk, 2.68; 95% CI, 1.10-6.49) increased the risk of asthma. Cough duration, the cough score, the family history of asthma, and serum eosinophilia were not found discriminative for the final diagnosis. There were no differences among children who eventually developed asthma and responded to either the 2-week or 8-week trial in terms of the study parameters.
Chronic NIC does not recur in the majority of children. Initial response to the ICS trial may be misleading but the trial may be preferred for children who have atopic sensitization, a previous history of chronic cough, or both .