The pattern of skin test reactivity to aeroallergens in asthmatic children in Riyadh

Increased prevalence of asthma in Saudi Arabia

BACKGROUND

Bronchial asthma is among the most common chronic illnesses of childhood. A number of reports in the recent past suggest that the prevalence of asthma is increasing globally.

OBJECTIVE

To investigate the changing prevalence of asthma in the Kingdom of Saudi Arabia.

SUBJECTS AND METHODS

Two populations of schoolchildren between the ages of 8 and 16 years were studied using an internationally designed protocol in 1986 and 1995. The questionnaire used in these studies was very similar to the one used in the International Study of Allergy and Asthma in Childhood. A total of 2,123 school-children in 1986 (Jeddah and Riyadh) and 1,008 schoolchildren in 1995 (Hail and Gizan) were enrolled in the surveys. These cross-sectional studies of randomly selected schoolchildren were statistically analyzed using ANOVA and a Z test.

RESULTS

The comparison of data between Riyadh versus Hail (inland desert dry environment) and Jeddah versus Gizan (coastal humid environment) revealed that the prevalence of asthma in the similar populations increased significantly from 8% in 1986 to 23% in 1995 (P < .0001). Likewise, the prevalence of allergic rhinitis also increased from 20% to 25% (P < .003) since 1986. However, no significant change in the prevalence of eczema (from 12% to 13%) was noted between 1986 and 1995.

CONCLUSIONS

The study indicates that there was a significant increase in the prevalence of bronchial asthma and, to a lesser extent, in the prevalence of allergic rhinitis in the Kingdom of Saudi Arabia during this 9-year period. The study also revealed increased exposure to environmental factors such as tobacco smoke and indoor animals in Saudi houses. It seems that the continuing changes in contemporary life may well have contributed to the increased prevalence of asthma in the country.

Pattern of immediate type hypersensitivity reactions in the Eastern Province, Saudi Arabia

BACKGROUND

In the period between July, 1992, and July, 1994, 1,159 patients in our Allergy Clinic tested positive to one or more inhalants. The nationalities of the population tested included 806 Saudi Arabs and 241 Western expatriates (mainly North Americans). The others were of various different nationalities.

OBJECTIVES

Our objective was to determine the pattern of immediate type hypersensitivity reactions among the atopic population in the Eastern Province of the Kingdom of Saudi Arabia.

METHODS

A standard prick skin test was applied and the reaction was considered positive if there was a 3-mm wheal associated with 10 mm of erythema, greater than the negative control.

RESULTS

The ten most common reactions in the Saudi Arab patients were as follows: Chenopodium album 53%, Kochia 51%, mesquite 46%, cottonwood 38%, alfalfa 36%, dust mite-farinae 36%, cockroach 35%, house dust 31%, Bermuda grass 29%, and acacia 29%. For North American expatriates living in the area, the ten most common reactions were: dust mite-farinae 43%, house dust 41%, Alternaria 36%, grass mix 34%, Bermuda grass 33%, mesquite 32%, cat 31%, Kochia 28%, alfalfa 24%, and Chenopodium album 24%.

CONCLUSIONS

Hypersensitivity to pollens, house dust, dust mite and cockroach was common. Mold and cat allergies were only common among Western expatriates.