Humoral immune factors and asthma among American Indian children: a case-control study.
BACKGROUND
Asthma is recognized as intimately related to immunologic factors and inflammation, although there are likely multiple phenotypes and pathophysiologic pathways. Biomarkers of inflammation may shed light on causal factors and have potential clinical utility. Individual and population genetic factors are correlated with risk for asthma and improved understanding of these contributions could improve treatment and prevention of this serious condition.


METHODS
A population-based sample of 108 children with clinically defined asthma and 216 control children were recruited from a small community in the northern plains of the United States. A complete blood count, high sensitivity C-reactive protein, total IgE and specific antibodies to 5 common airborne antigens (CAA), in addition to basic demographic and anthropomorphic data were obtained. Logistic regression was primarily used to determine the association between these humoral factors and risk of asthma.


RESULTS
The body mass index (BMI) of those with asthma and their total leukocyte counts, percentage of eosinophils, and levels of total IgE were all greater than corresponding control values in univariate analysis. The presence of detectable, specific IgE antibodies to five common airborne antigens was more likely among cases compared with controls. In multivariate analysis, total IgE was independently associated with asthma; but not after inclusion of a cumulative measure of specific IgE sensitization.


CONCLUSIONS
Many previously reported associations between anthropomorphic and immune factors and increased risk of asthma appear to be also present in this American Indian population. In this community, asthma is strongly associated with sensitization to CAA.
Missouri Breaks Industries Research Inc, Eagle Butte, SD, USA. lbest@restel.com.|Turtle Mountain Community College, Belcourt, ND, USA. lbest@restel.com.|, 1935 118th Ave NW, Watford City, ND, 58854, USA. lbest@restel.com.
Lyle G
LG
Best
Missouri Breaks Industries Research Inc, Eagle Butte, SD, USA.
Rae A
RA
O'Leary
Missouri Breaks Industries Research Inc, Eagle Butte, SD, USA.
Marcia A
MA
O'Leary
Missouri Breaks Industries Research Inc, Eagle Butte, SD, USA.
Joseph M
JM
Yracheta
D000293:Adolescent; D000485:Allergens / Q000276:immunology*; D001249:Asthma / Q000208:ethnology*; D002097:C-Reactive Protein / Q000032:analysis*; D016022:Case-Control Studies; D002648:Child; D005260:Female; D006801:Humans; D056724:Immunity, Humoral; D007073:Immunoglobulin E / Q000097:blood*; D007198:Indians, North American; D007958:Leukocyte Count; D016015:Logistic Models; D008297:Male; D015999:Multivariate Analysis; D014481:United States / Q000208:ethnology
D000485:Allergens; D007073:Immunoglobulin E; D002097:C-Reactive Protein
Airborne allergens; Allergen specific IgE; American Indian; Asthma; C-reactive protein; Children; Eosinophils; IgE; Immunoglobulin