Atopy and Asthma in Migrants

Abstract

Atopy and asthma result from the effects of environmental factors on genetically susceptible persons, and different prevalence rates have been documented worldwide. In developed and industrialized countries a higher prevalence of atopy and asthma is observed as compared with undeveloped and less affluent countries. Migration involves exposure to a new set of pollutants and allergens. In addition, it involves several socioeconomic and cultural issues such as housing conditions, diet and accessibility to medical services, all of which are likely to affect migrants’ health. Migration studies provide information on the role of environmental factors in the development of atopy and asthma. Immigration to allergy-prevalent countries causes more allergies and asthma in immigrants as compared to the prevalence of atopy in their countries of origin. The increase in allergy and asthma is usually not related to ethnicity, but in certain populations may play an important role. Studies on migrants support the notion that lifestyle and environmental factors in western industrialized countries facilitate atopy and asthma. The effect is time-dependent. Acquiring allergy is influenced by the age at the time of immigration. Migrants, in general, are more prone to the development of allergies than the local population. Low hygiene prior to immigration does not seem to protect against the development of atopy or asthma. Vaccinations do not affect the development of atopy or asthma in the general population and in migrants. Migrants should be aware of the potential of developing allergies and/or asthma. Strategies for primary prevention in high-risk atopic individuals and secondary prevention guidelines should be developed both for populations in developing countries as well as for immigrants from such countries to atopy-prevalent developed countries.

Climate change and respiratory diseases

“…Migration studies provide useful information on the role of environmental factors, including climate changes, and on the development of atopy and asthma [48][49][50][51]. Migration involves exposure to a new set of air pollutants and allergens, as well as changes in housing conditions, diet and accessibility to medical services, all of which are likely to affect migrants' health.…”

The impact of ethnicity on asthma care

“…pollutants and allergens) and conditions (e.g. housing and diet), 10 or changes in lifestyle (e.g. Westernised diet) and behaviour (e.g.…”

Atopic Dermatitis and Type 1 Diabetes Mellitus in Iranian Children

“…The study carried out by Rosenbauer and collagues in Germany 2003 indicates that atopic eczema in early childhood could be protective against T1D [5] , however another study carried out in Netherlands by Meerwaldt and collagues [4] shows the lower prevalence of asthma, hay fever and eczema symptoms in DM patients compared with age-matched controls, although not statistically significant, is consistent with the Th1/Th2 concept [6] . The aim of our study is to determine the association between these two diseases, in our city, because such studies were not conducted in this region and if we can found an association, further studies are needed to determine the pathogenesis.…”

“…(200 mg dL −1 ) during an oral glucose tolerance test [5] It seems that T1D has a Th1 (T-helper 1) immune reactivity pattern. There is often a reciprocal relationship between Th1 immune responses, which suggests that AD (Th2 phenotype) and T1D (Th1 Phenotype) are unlikely to coexist in the same individual [2] .…”