Early School Years follow up of the Asking Questions in Alcohol Longitudinal Study in Melbourne, Australia (AQUA at 6): Cohort profile

Abstract

Purpose The Asking Questions about Alcohol in Pregnancy (AQUA) study, established in 2011, is a pre-birth cohort of 1570 mother and child pairs designed to assess the effects of low to moderate prenatal alcohol exposure and sporadic binge drinking on long-term child development. The current follow-up of the children, now aged 6 to 8 years, aims to strengthen our understanding of the relationship between these levels of prenatal alcohol exposure and neuropsychological functioning, facial dysmorphology, and brain structure & function. Findings to date Over half (59%) of mothers consumed some alcohol during pregnancy, with one in five reporting at least one binge drinking episode prior to pregnancy recognition. Children’s craniofacial shape was examined at 12 months of age, and low to moderate prenatal alcohol exposure was associated with subtle midface changes. At two years of age, formal developmental assessments showed no evidence that cognitive, language or motor outcome was associated with any of the prenatal alcohol exposures investigated. Participants Between June 2018 and April 2021, 802 of the 1342 eligible AQUA study families completed a parent-report questionnaire (60%). Restrictions associated with COVID-19 pandemic disrupted recruitment, but early school-age neuropsychological assessments were undertaken with 696 children (52%), and 482 (36%) craniofacial images were collected. A pre-planned, exposure-representative subset of 146 random children completed a brain MRI. The existing AQUA study biobank was extended through collection of 427 (32%) child buccal swabs. Future plans We will investigate the relationship between prenatal alcohol exposure and specific aspects of neurodevelopment at 6-8 years, including brain structure & function. We will also determine whether craniofacial changes identified at 12 months of age are predictive of later developmental impairments. The contribution of genetics and epigenetics to individual variations in outcomes will be examined in conjunction with established and future national and international collaborations. STRENGTHS AND LIMITATIONS The Asking Questions about Alcohol in Pregnancy (AQUA) cohort study was specifically designed to prospectively collect high-quality data on low to moderate prenatal alcohol exposure and relevant confounders to investigate the risk to offspring neurodevelopment. The children are being followed up for the third time at 6-8 years, using sensitive measures of neuropsychological function, 3D craniofacial photography, and brain MRI. A biobank of birth samples and maternal and child buccal DNA enables investigation of the contribution of genetic and epigenetic factors to neurodevelopmental outcomes. Despite carefully designed questions, reporting bias will need to be considered in the interpretation of findings, especially around alcohol use. The generalisability of some findings will be limited to a general antenatal population of Caucasian women, from middle-income backgrounds and with a low-risk pregnancy.