Time trends and seasonal variations in hospital admissions for childhood asthma in Taiwan from 1990 to 1998.

The aim of the study was to determine the trends and seasonal variations in hospital admissions for childhood asthma in a tertiary medical center since 1990. Data were collected according to the age and sex of patients and obtained from hospital registries between 1990 and 1998. Children between 2 and 14 years of age admitted with the diagnosis of asthma, or asthmatic bronchitis (ICD-9 code 493) were included. Age-specific and sex-specific hospital admission rates for asthma were calculated for each calendar year. The asthma admission rates were defined as the number of asthma admissions divided by the total number of all pediatric admissions in a year. Seasonal admission rates were calculated in a similar fashion. In addition, the number of readmissions was also calculated during the study period with comparisons of sex and age differences. The asthma admission rates showed a significant upward trend throughout the period studied, particularly among the 2-4 years of age group (relative risk = 2.08; p = 0.0001). Seasonal admission rates revealed a statistically significant increase during the October-December period, peaking in November or December of each calendar year (relative risk = 1.84; p = 0.0001). There was a male predominance in both age categories during the 9-year period. Comparisons of readmissions for asthma (at least three admissions) disclosed that girls were far more likely to be readmitted than boys among the 5-14 years of age group (p = 0.01). Our results indicate 1) an increased prevalence and severity of childhood asthma in Taiwan; 2) boys and younger children aged 2-4 years with asthma had increased risks of admission for asthma (relative risks were 1.22 and 1.96, respectively) and 3) girls among the older children with asthma tend to present with greater severity than boys owing to higher relative risks of readmission for asthma.

Serum eosinophil cationic protein determination in asthmatic children-effect of different collecting tubes used for blood sampling.

We compared the effect of using 2 different serum collecting tubes, serum separation tubes (SST, with clot activator and gel barrier) and conventional glass tubes (with no additives), on circulating levels of eosinophil cationic protein (ECP) in asthmatic children and controls. The serum ECP values obtained from both SST and glass tubes were significantly higher in asthmatic children than in corresponding controls. ECP values were higher in serum samples using SST than in those using glass tubes (P<0.01), while no difference was found between the two in controls. ECP levels correlated with peripheral eosinophil counts, for SST samples and glass tube samples alike. The difference in ECP levels between these two tubes also correlated with circulating eosinophil counts (r = 0.62, P = 0.004) After 18-hour storage at room temperature, the ECP values increased significantly in samples obtained from asthmatic children. No difference in ECP values between SST samples and glass tube samples was found for 18 hour samples. Thus, ECP levels obtained from SST samples and glass tube samples, though reliable, should not be directly compared, especially in asthmatic children with eosinophilia.