Allostatic Load Biomarkers and Asthma in Adolescents

Rationale: Allostatic load (AL), a novel measure of the physiologically dysregulated response of the body to stress, represents a biomarker of chronic stress exposure. Objectives: To determine whether preadolescent children with high AL are more susceptible to asthma as adolescents. Methods: This was a prospective evaluation of children recruited at 7 to 10 years of age in the nested case-control arm of the Study of Asthma, Genes and Environment and followed until 11 to 14 years of age. AL was measured using eight biomarkers: fasting glucose, total cholesterol, high-density lipoprotein cholesterol, dehydroepiandrosterone sulfate, cortisol, systolic and diastolic blood pressure, and waist-to-hip ratio. AL, created from the sum of biomarkers in a high-risk quartile, was related to prevalence and incidence of asthma using logistic regression. Measurements and Main Results: Among 352 participants followed until 11 to 14 years of age, prevalent asthma was four times more likely in boys with high (>3) versus low (<= 2) AL after adjusting for current asthma/atopy, age, ethnicity, parental history of asthma, and overweight status. Similar results were observed in the analysis of new-onset asthma in boys (adjusted odds ratio, 4.35; 95% confidence interval, 1.19-15.9). In girls, there were no associations between AL and asthma. In the analysis of a subset of biomarkers, combinations of total cholesterol, glucose, and cortisol were associated with similar or greater risk of asthma prevalence or onset in boys. Conclusions: AL and its biomarkers are associated with an increased likelihood of asthma in adolescent boys. The observed association between AL and asthma may be attributable to a combined subset of AL biomarkers.