Document Type : Original Article


1 Department of Pediatric Pulmonology, Child Growth and Development Research Center, Research Institute for Primordial Prevention of Non-Communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran

2 NonCommunicable Diseases Research Center, Alborz University of Medical Sciences, Karaj, Iran,

3 Department of Pediatrics, Ziaeian Hospital, Tehran University of Medical Sciences, Teharan, Iran,

4 Research Center for Immunodeficiencies, Pediatrics Center of Excellence, Children’s Medical Center, Tehran University of Medical Science, Tehran, Iran


BACKGROUND: Some evidence suggests that childhood croup could be associated with increased
incidence of adulthood bronchial reactivity, but its significance is uncertain. The aim of the present
study was to evaluate the long‑term outcome of early life croup.
PATIENTS AND METHODS: This case–control study was conducted in 2010–2012 in Isfahan,
Iran. The case group consisted of 164 adolescents with a history of severe croup in early life and an
equal number of healthy controls without any history of croup or other chronic or recurrent respiratory
diseases. The two groups were compared according to pulmonary function tests and bronchial
reactivity (exercise challenge test). Statistical analyses were performed using the SPSS software
package, version 20 (SPSS Inc., Chicago, IL, USA). P < 0.05 was considered significant.
RESULTS: Baseline spirometric values (forced expiratory volume in 1st s (FEV1), forced volume
capacity (FVC), FEV1/FVC, and forced expiratory flow at 25%–75% (FEF25–75) were similar in case
and control groups. A reduction in FEV1 and FEF25–75 after exercise challenge test was seen in
9% and 12.8% of patients, respectively, whereas this was reduced in only 4.2% and 6.1% of the
controls (P = 0.034 and P = 0.021, respectively).
CONCLUSION: Our findings suggest that childhood croup might be a predisposing factor for bronchial
hyperreactivity in adulthood. Longitudinal studies are necessary to confirm the clinical significance
of these findings.


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