THE ASSOCIATION BETWEEN PERINATAL AND EARLY LIFE EXPOSURES AND LUNG FUNCTION IN AUSTRALIAN ABORIGINAL YOUNG ADULTS: THE AUSTRALIAN ABORIGINAL BIRTH COHORT STUDY

Background Lung function in early adulthood has been shown to influence future morbidity and mortality. Its impact may vary across ethnic groups due to potential gene-environment interactions. There are limited data on risk factors for lung function deficits amongst the Australian Aboriginal population, particularly on early life exposures. The aim of our study was to investigate the association of perinatal and early life exposures on lung function in this population. Methods We used data from the Australian Aboriginal Birth Cohort (ABC), a birth cohort of 686 singleton babies born to a mother who self-identified as either Aboriginal and/or Torres Strait Islanders. Linear regression was used to evaluate the association between perinatal and early life exposures with FEV1, FVC, FEV1%predicted, FVC%predicted and FEV1/FVC ratio as individual outcomes in turn. Age, sex, height and smoking status were identified as a priori confounders for FEV1, FVC and FEV1/FVC. Smoking status was an a priori confounder for FEV1 and FVC% predicted. We used Directed Acyclic Graphs to identify minimally sufficient adjustment set of confounders. Results 459 (70.7%) participants were followed-up, of which spirometry undertaken on 312 but only 148 spirometry traces were deemed acceptable and included in subsequent analyses. The cohort mean age was 25.8 years (SD=1.1) and 74 (50%) were male. 62.8% were current smokers, 68.9% lived in remote communities and 58.8% depended on benefits as their main source of income. We found that 59 people (39.9%, 95%CI 31.9–48.2) had abnormal spirometry patterns (38 restrictive, 21 obstructive). Lung function parameters were strongly associated with maternal age, respiratory hospitalizations in early childhood and place of residence at birth (table 1). Conclusion Spirometry deficits are common in our cohort. Pre-school hospitalisations for respiratory infections and living remotely are risk factors for lower lung function in young Australian Aboriginal adults whilst increased maternal age is associated with better lung function. Studies evaluating perinatal and early life interventions that optimise attainment of normal lung function are required to minimise future morbidity and mortality in Aboriginal adults.