Understanding neuropsychiatric outcomes of traumatic brain injury

Severe brain injury has well-evidenced impacts on cognition, behaviour and adaptive functioning and is a known risk factor for the later development of psychiatric disorder.1 However, the spectrum of acquired brain injury includes mild and moderate traumatic brain injury which may not result in a clinical referral. There is early evidence that these may also raise the longer-term risk for psychiatric disorder - in a time span of years rather than weeks or months,2 although this has not been well-studied. One difficulty in this area is that the vast majority of studies are clinical follow-up studies, which are biased towards inclusion of more severe cases.3
This PhD project will take a systematic approach to characterising the neuropsychiatric impact of brain injury by conducting careful epidemiological analysis of existing longitudinal cohort studies. This will allow the neuropsychiatric outcomes of brain injury to be studied at different stages of the lifespan, as well as over longer-term follow-up periods. By using population studies, rather than data from clinical follow-ups, this will allow for a broader understanding of how mild and moderate brain injuries impact on neuropsychiatric outcomes.
Study 1 will use data from the ongoing Adolescent Brain Cognitive Development (ABCD) study being conducted in the United States.4 It has recruited 11,000+ children from 9-10 years of age who are measured annually or biannually across a number of variables, including physical health, mental health, cognition, neuroimaging and social and family environment.
Study 2 will use the Avon Longitudinal Study of Parents and Children (ALSPAC) dataset that has followed children recruited in the 1990s to adulthood in the present day.5 Participants are assessed for physical health, mental health, cognition, and social and family environment. Previous studies have examined the impact of child brain injury on cognitive outcomes but not neuropsychiatric outcomes.
Study 3 will use the UK BioBank dataset that has followed 500,000 volunteers in the UK enrolled at ages from 40 to 69 in 2006.6 It records a wide range of physical and mental outcomes, as well as data on social environments, cognition and neuroimaging. One study has used the UK BioBank to examine cognitive outcomes of traumatic brain injury but none to date have examined neuropsychiatric outcomes.
This PhD will make an important contribution to our understanding of outcomes of traumatic brain injury using longitudinal population studies that can be controlled for a range of potential confounders and can examine the influence of pre- and post-injury factors.

References
1. Bhalerao SU, Geurtjens C, Thomas GR, Kitamura CR, Zhou C, Marlborough M. Understanding the neuropsychiatric consequences associated with significant traumatic brain injury. Brain Injury. 2013 Jul 1;27(7-8):767-74.
2. Sariaslan A, Sharp DJ, D'Onofrio BM, Larsson H, Fazel S. Long-Term Outcomes Associated with Traumatic Brain Injury in Childhood and Adolescence: A Nationwide Swedish Cohort Study of a Wide Range of Medical and Social Outcomes. PLOS Medicine. 2016 Aug 23;13(8):e1002103.
3. Tagliaferri F, Compagnone C, Korsic M, Servadei F, Kraus J. A systematic review of brain injury epidemiology in Europe. Acta Neurochir (Wien). 2006 Mar 1;148(3):255-68.
4. Casey BJ, Cannonier T, Conley MI, Cohen AO, Barch DM, Heitzeg MM, et al. The Adolescent Brain Cognitive Development (ABCD) study: Imaging acquisition across 21 sites. Developmental Cognitive Neuroscience. 2018 Aug 1;32:43-54.
5. Golding, Pembrey, Jones, Team TAS. ALSPAC-The Avon Longitudinal Study of Parents and Children. Paediatric and Perinatal Epidemiology. 2001;15(1):74-87.
6. Sudlow C, Gallacher J, Allen N, Beral V, Burton P, Danesh J, et al. UK Biobank: An Open Access Resource for Identify the Causes of a Wide Range of Complex Diseases of Middle and Old Age. PLOS Medicine. 2015 Mar 31;12(3):e1001779.