Recent 5-year trends of asthma severity and allergen sensitization among children in southern Thailand

Abstract

BACKGROUND: Asthma is a major public health issue that affects morbidity. The greater severity of asthma requires more health care resource utilization. OBJECTIVE: To investigate the possible changes in disease severity and allergen sensitization of children with asthma in an interim period of 5 years. METHODS: We retrospectively reviewed the charts of 200 patients with established asthma in the pediatric allergy clinic. The data were collected in different time periods with 100 consecutive cases in each group starting in January of 2004 and in January of 2009. All patients underwent a skin prick test (SPT) to common allergens, with positive and negative controls. SPTs with a mean wheal diameter 3 mm greater than a negative control were considered test-positive. RESULTS: The mean ages of patients in the 2004 and 2009 groups were 7.54 and 7.73 years. Compared with patients in the 2004 group, the 2009 group had more severe asthma (p = 0.006). The distribution of asthma severity was mild (intermittent and mild persistent) 98.0% in 2004 and 87.9% in 2009, and moderate to severe persistent 2.0% in 2004 and 12.1% in 2009. The prevalence of patients sensitized to both house dust (HD) and house dust mites (HDM) increased from 21.2% in 2004 to 34.3% in 2009 (p =0.007). Sensitization to allergens of HD, HDM and cockroach increased to 14.1% in 2009 from 9.1% in 2004 (p =0.021). CONCLUSIONS: During the years between 2004 and 2009, asthma severity increased with increasing sensitization to HD, HDM and cockroach. Awareness of these changes and further studies are required.