Regional Variation in the Prevalence of Asthma Symptoms among Omani School Children Comparisons from Two Nationwide Cross-sectional Surveys Six Years Apart

The International Study of Asthm a and Allergies in Children (ISAAC) highlighted the presence of wide variations in asthma prevalence between and within countries . The aim of this study was to determine the changes in the prevalence of asthma and its symptoms across the different regions of Oman. Methods: Two cross-sectional surveys were conducted as part of ISAAC phases I (1995) and III (2001) in two age groups (6-7 and 13 -14 years) from nation -wide samples of Omani school children, with 7 ,0 67 participants in 1995 (3, 893 young and 3,174 older group) and 7,879 participants in 2001 (4,126 young and 3,753 older group). Results: Over the period of six years, the Sharqiya (Eastern ) region continued to have the highest prevalence of self-reported asthma diagnosis and all asthma symptoms in both age groups, with a significant increase in the prevalence of wheeze in the past 12 months (from 8 .7% to 13.8 %; P=0.00 2) and asthma diagnosis (from 13.8% to 17.8 %; P=0.046) in the young group, and a significant increase in night cough (from 21.6% to 27.8%;p=0.039) in the older group. All other regions had lower prevalence rates in 1995 in both age groups, and showed either no significant change or a decline in one or two of the self-reported asthma symptoms. The prevalence of asthma diagnosis among wheezy children remained unchanged across all regions. In addition , asthma under-diagnosis remains a problem with only 60% of children with severe wheeze reporting asthma diagnosis in both surveys. Conclusion :The geographic variation in the prevalence of self-reported of asthma symptoms among Omani school children persists with further increase in the Sharqiya region. The findings also suggest under -diagnosis and/or poor recognition of asthma which had not improved over time.