Systematic review: long‐term cognitive and behavioural outcomes of neonatal hypoxic–ischaemic encephalopathy in children without cerebral palsy

AIM: To evaluate long-term cognitive and behavioural outcomes of children with neonatal hypoxic-ischaemic encephalopathy (HIE) in the absence of cerebral palsy (CP). METHODS: A systematic search was performed on five databases (EMBASE, Medline, PubMed, Web of Science, PsycInfo). Randomised controlled trials, non-randomised controlled trials, or observational studies, published between 1990 and 2017, that reported long-term (age greater than or equal to four years) cognitive and/or behavioural outcomes of neonatal HIE without CP were included. RESULTS: Seven articles met the inclusion criteria (n = 352 total participants, n = 53 treated with therapeutic hypothermia). Studies reporting cognitive outcome demonstrate impairment of general cognitive abilities in 25-63% of participants with HIE without CP. Specific cognitive difficulties were reported in two studies for attention, executive functioning, memory function and language. Results regarding behavioural outcome possibly indicate a higher risk of difficulties. CONCLUSION: A substantial proportion of children with neonatal HIE who survive without CP are at increased risk of general and/or specific cognitive impairments. Behavioural problems may be more common, but evidence is limited. Results highlight the importance of comprehensive long-term follow-up to identity difficulties and enable intervention to optimise educational achievement and behavioural adjustment.