Efficacy and feasibility of the BREATHE asthma intervention with American Indian children: a randomized controlled trial.

American Indian (AI) children experience significant disparities in asthma prevalence, severity, and burden of disease, yet few asthma education interventions are tested in this population. This study aimed to evaluate the efficacy and feasibility of the BREATHE intervention with parents and AI children, during a 3-year follow-up period (n = 108), using a randomized controlled design. Children with asthma identified by electronic medical records (EMR) were screened and matched with 2 controls. The intervention included an initial educational and 24 months of follow-up. The control group continued their usual care. The primary outcome was the frequency of EMR documented, emergency department (ED) visits or hospitalization for respiratory complaints. There was no statistical difference in mean primary outcomes (1.34 (1.98) vs 1.22 (1.95), - 0.88 to 0.63, 95% CI of the difference, p = 0.75), nor percent with any ED visit or hospitalization (29/53, 55% vs 30/55, 54%, p = 0.99) between the intervention or control groups respectively. After 365 days, there was a borderline significant difference in time to primary outcome. Although limited in power, the present study did not demonstrate a persistent effect of this intervention. We recommend that AI pediatric asthma interventions are culturally-designed, use feasible procedures, and repeat education at least every 12 months.

Genetic variants and risk of asthma in an American Indian population.

BACKGROUND: Asthma is recognized as a complex, multifactorial disease with a genetic component that is well recognized. Certain genetic variants are associated with asthma in a number of populations. OBJECTIVE: To determine whether the same variants increase the risk of asthma among American Indian children. METHODS: The electronic medical records of an Indian Health Service facility identified all children between 6 and 17 years of age with case-defining criteria for asthma (n = 108). Control children (n = 216), matched for age, were also identified. Real-time polymerase chain reaction assays were used to genotype 10 single-nucleotide polymorphisms (SNPs) at 6 genetic loci. Genotypic distributions among cases and controls were evaluated by χ2 and logistic regression methods. RESULTS: A variant at 5q22.1 revealed a statistically significant imbalance in the distribution of genotypes between case-control pairs (rs10056340, P < .001). In logistic regression analyses, the same variant at 5q22.1 and a variant at 17q21 were associated with asthma at P < .05 (rs10056340 and rs9303277). Inclusions of age, body mass index, and atopy in multivariate models revealed significant associations between rs10056340 (odds ratio, 2.020; 95% confidence interval, 1.283-3.180; P = .002) and all 5 17q21 SNPs and asthma in this population. In analyses restricted to atopic individuals, the association of rs10056340 was essentially unchanged, whereas among nonatopic individuals the trend was in the same direction but nonsignificant. The reverse was true for the 17q21 SNPs. CONCLUSION: These findings demonstrate that many variants commonly associated with asthma in other populations also accompany this condition among American Indian children. American Indian children also appear to have an increased risk of asthma associated with obesity.

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. CONCLUSION: 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.