HIGH-RATE OF ASTHMA AMONG IMMIGRANTS

Articles dealing with the epidemiological aspects of asthma were caref ul ly reviewed in order to support or reject our clinical impression o f increased rate of asthma among immigrants. Particular emphasis was p ut on data on very high or very low rates of asthma. The proposed theo ries to explain these differences were critically examined. The preval ence of asthma in China and in Africa is 1-2% and 0.5-5%, respectively . The prevalence of the disease in other indigenous populations ranges between 0.5% and 12%. On the other hand, asthma is much more frequent ly seen in Australia and in New Zealand (approximately 20-25%), where peoples' ancestors immigrated from distant areas. Statistical meta-ana lysis found a significant difference between the rates of asthma in th e two groups of populations (P< 0.001). Immunoglobulin E levels of imm igrants in Sweden are higher than those of native Swedes. Similarly, c ord blood immunoglobulin E concentrations are more elevated in neonate s whose mothers emigrated to Germany from Eastern countries than in th ose of native German mothers. There is an increased rate of IgE-mediat ed asthma among immigrant populations.