A One-Year Prognosis of Preschool Children Hospitalized with Acute Wheezing in Thailand

Background: Wheezing in preschool children is a common symptom. Genetic with environmental factors might be responsible for their prognosis.

Objective: The study aimed to determine an incidence of recurrent wheezing among preschool children who hospitalized with acute wheezing after a follow-up period of 12 months. Factors associated with recurrent wheezing were explored.

Method: A longitudinal study was conducted among 240 children, aged between 6 months and 5 years, who hospitalized with acute wheezing in 4 hospitals located in Bangkok and adjacent provinces, Thailand. Demographic, house environments and clinical characteristic data were collected at entry. Serum specific IgE levels against common food and inhalant allergens and serum 25-hydroxyvitamin D concentrations were measured. All children were followed every 4 months for 12 months to record emergency or unscheduled visits due to recurrent wheezing. Exploratory analysis by multiple logistic regressions was used to determine significant factors associated with recurrent wheezing.

Results: At entry, the mean age was 24.4 months (SD=15.7 months) with 148 boys (62.7%). Ninety-four cases (40.9%) were hospitalized with the first wheezing episode of their life. By laboratory results, 197 (82.8%) and 56 (24.9%) children were atopic and had vitamin D insufficiency respectively. The one-year incidence risk of emergency visits due to recurrent wheezing among those with the first wheezing episode and those with history of previous wheezing at entry were 42.3% (95% confidence interval: 31.2%-54.0%) and 55.6% (95% confidence interval: 46.1%-64.9%) respectively. By multivariate analysis, being the second child or more, vitamin D insufficiency, previous wheezing, and allergic rhinitis were significantly associated with recurrent wheezing with the adjusted odds ratios of 2.5 (95% confidence interval: 1.3-5.3), 2.3 (95% confidence interval: 1.1-4.5), 1.9 (95% confidence interval: 1.1-3.5), and 1.6 (95% confidence interval: 1.3-2.9) respectively.

Conclusion: Recurrent wheezing in preschool children was common. Being the second child or more in the family, vitamin D insufficiency, previous wheezing, and allergic rhinitis were significant risks of recurrent wheezing.