Prevalence and severity of Asthma symptoms in children of Tehran international study of asthma and allergies in childhood [ISAAC]

ABSTRACT

This descreptive study was conducted to determine the prevalence of asthma and related symptoms among 6-7 and 13-14 year old school children in Tehran as a part of International study of Asthma and Allergies in childhood [ISAAC] phase Ill. The ISAAC written questionnaire was given to a total of 6127 students of 72 schools in urban area of Tehran. Simple random sampling was performed with a uniform distribution throughout 12 clusters of 2 divisions of the municipality. All 6-7 and 13-14 year old students were enrolled in this study. Results showed that 15% of the 6-7 year olds and 17% of the 13-14 year olds had positive history of wheezing among which 8.6% and 10.6% respectively had had recent attacks. Physician confirmed asthma was reported in 2.1% of the 6-7 year olds and 2.6% of the 13-14 age group. Severity of asthma assessed by frequency of speech limitation due to wheeze was positive in 1.5% of 6-7 aged group and 3% of 13-14 year olds. Exercise induced wheeze was detected in 2.3% of the 6- 7year old group compared to 15.3% of the 13-14 year olds. Nocturnal cough was more prevalent among 13-14 year olds [18.4%] compared to only 7.2% in the 6-7 year olds. Overall, no significant change in prevalence of asthma symptoms has occurred since 1997 [the last phase of ISAAC] among children of Tehran. The results of our study suggest higher rates of confirmed asthma among 6-7 years old girls compared to boys. However, more extensive and precisely designed studies are needed to further confirm these findings: