''United Airways Disease'' and Phenotypic Peculiarities of Respiratory Allergy in Immigrants

Abstract

Allergy is the result of a complex interaction between genetic background and environmental factors, including exposure to allergens and lifestyle. Migration is a process that involves many radical changes in the environment, including diet, pollutants, allergens, different housing conditions, and patterns of infections. Thus, studies in immigrants may provide important information about the role of environmental factors in the development of allergic respiratory diseases. Several studies addressed this aspect and consistently found that migrants develop allergies at different rates from the local population, and very often the symptoms appear with a delay of 3 to 5 years after migration. More recent data showed that the severity of allergic diseases is greater in migrants, and that usually the onset is with associated asthma and rhinitis. The immigration model strongly suggests that environmental factors overcome the genetic background, and that the clinical phenotype of respiratory allergy in migrants has some peculiarities.

Environmental and Genetic Factors Modulating Immune Responses: A Preliminary Survey of Allergic Rhinitis and CoMorbid Conditions in Immigrants to North America

“…Perhaps, a longitudinal study may reveal further information on the pathogenic role of local environmental conditions in sensitized individuals. Further studies consistently found that immigrants tended to develop allergies at different rates with symptoms often appearing 3 to 5 years after settlement into new environment [13]. This was observed in our study as more migrants in our study reported developing allergy after migration.…”

“…Numerous studies have concluded that any mutations or changes to genetic background would take many years and would affect the next generation whereas environmental conditions such as pollution, variability in microbiota and quite possibly genetically modified foods would account for the increasing development of allergic reactions [13,14]. In our study, alcohol consumption was the most reported factor among immigrant and nonimmigrant population, while food allergies, decrease sleep and lactose intolerance were also reported.…”

“…There is now evidence that these environmental exposures can modify early immune gene expression through potentially heritable epigenetic changes [11,15]. Vitamin D also known as the "sunshine hormone" plays an important role in both adaptive and innate immune functions involved in the development and progression of allergic diseases [13,16]. Various studies, both clinical and experimental, over the years have been done to investigate whether vitamin D insufficiency has a role in allergic prevalence [measured as serum 25 hydroxy vitamin D-25(OH)D] [16].…”

“…Various studies, both clinical and experimental, over the years have been done to investigate whether vitamin D insufficiency has a role in allergic prevalence [measured as serum 25 hydroxy vitamin D-25(OH)D] [16]. Vitamin D is known to mimic various immune cells, monocytes, dendritic cells, T and B cells, and various functions of epithelial cells thus forming a barrier against allergens and controlling and promoting regulatory immune response and defense [12,13,16]. Early exposure to vitamin D may prove to be beneficial and may promote mucosal defense and allergen tolerance and in turn help maintain healthy microbial immune system [13,16].…”

“…Vitamin D is known to mimic various immune cells, monocytes, dendritic cells, T and B cells, and various functions of epithelial cells thus forming a barrier against allergens and controlling and promoting regulatory immune response and defense [12,13,16]. Early exposure to vitamin D may prove to be beneficial and may promote mucosal defense and allergen tolerance and in turn help maintain healthy microbial immune system [13,16]. Although more patients in our study reported taking supplement among the factors affecting allergies, majority of our sampled patients reported that they do not take supplement.…”