Motor testing at 1 year improves the prediction of motor and mental outcome at 2 years after perinatal hypoxic–ischaemic encephalopathy

Abstract

To investigate the predictive value of motor testing at 1 year for motor and mental outcome at 2 years after perinatal hypoxic-ischaemic encephalopathy (HIE) in term neonates. Motor and mental outcome at 2 years was assessed with the Bayley Scales of Infant Development, 2nd edition (BSID-II) in 32 surviving children (20 males, 12 females; mean gestational age 40.2 wk, SD 1.4; mean birthweight 3217g, SD 435) participating in a prospective cohort study of HIE. The predictive value of three motor tests (Alberta Infant Motor Scale [AIMS], BSID-II, and the Neurological Optimality Score [NOS]) at 1 year was analysed, in addition to predictions based on neonatal Sarnat staging and magnetic resonance imaging (MRI). Poor motor test results were defined as an AIMS z-score of <-2, a psychomotor developmental index of the BSID-II of <70, or a NOS of <26. Poor motor and poor mental outcome at 2 years was defined as a psychomotor developmental index or mental developmental index of the BSID-II of <70. Twelve children, all with Sarnat grade II, had a poor motor outcome and 12 children, of whom one had Sarnat grade I, had a poor mental outcome at 2 years. Nine children had cerebral palsy, of whom five had quadriplegia, three had dyskinesia, and one had hemiplegia. Poor motor tests at 1 year increased the probability of a poor motor outcome from 71% (range 92 to 100%), and a poor mental outcome from 59% (range 77 to 100%) in children with Sarnat grade II and abnormal MRI, assessed with the AIMS and BSID-II or NOS respectively. Additional motor testing at 1 year improves the prediction of motor and mental outcome at 2 years in children with Sarnat grade II and abnormal MRI.