Background: Some individuals are more susceptible than others to the effects of environmental factors, although the physiological reasons for this are unknown. This study investigates the fundamental association between some serum proteins and respiratory symptoms in Japanese children.
Methods: The serum alpha 1-antitrypsin (alpha 1AT), alpha 2-macroglobulin (alpha 2MG), and albumin concentrations were determined in 480 schoolchildren living in an area with low air pollution levels. Their respiratory symptoms were assessed from responses to questionnaires.
Results: Serum alpha 1AT levels were significantly lower in children with histories of allergic diseases, while their alpha 2MG levels were increased. Serum albumin levels were significantly decreased in children with asthma compared with those without, and the levels did not differ significantly for those children with wheezing symptoms or histories of allergic diseases. Serum alpha 1AT levels were only significantly lower in girls with asthma. Fourteen children (2.9%) were found to have decreased alpha 1AT levels of < 160 mg/dl. All of these children had histories of allergic diseases, and the prevalence of asthma was remarkably higher in these children. Children with only wheezing symptoms showed no significant changes in serum alpha 1AT, alpha 2MG, or albumin levels.
Conclusions: These findings suggest that serum alpha 1AT, alpha 2MG, and albumin levels are associated with respiratory and allergic diseases in children. A decreased alpha 1AT level should be considered as a biological risk marker for these diseases.