Hammersmith Infant Neurological Examination for infants born preterm: predicting outcomes other than cerebral palsy

Abstract

We explored the ability of the Hammersmith Infant Neurological Examination (HINE) to identify typical and delayed cognitive performance in a large population of infants born preterm, both with and without cerebral palsy (CP). We conducted a retrospective study of infants born preterm who had repeated HINEs between 3 and 12 months corrected age. At 2 years, cognition was assessed using the Mental Development Index (MDI; from the Bayley Scales of Infant Development, Second Edition) and the presence and severity of CP was determined. All children were classified as cognitively typical/mildly delayed or significantly delayed (MDI <70) and CP. The predictive validity of HINE scores for significantly delayed cognitive performance, in children with and without CP, was calculated using specific cut-off scores according to age at assessment. Of 1229 eligible infants (gestational age 25-36wks, mean [SD] 34.9 [2.3]; 646 males, 583 females), 1108 did not develop CP, 891 had an MDI that was typical/mildly delayed, and 217 had an MDI less than 70. Of the 121 infants who developed CP, the MDI was typical in 28, mildly delayed in 27, and less than 70 in 66. HINE scores showed a good sensitivity and specificity, especially after 3 months, for detecting significantly delayed cognitive performance in infants without CP. In those who developed CP, the score was associated with their cognitive level. The HINE provides information about the risk of delayed cognitive performance in infants born preterm with and without CP. What this paper adds The Hammersmith Infant Neurological Examination (HINE) can be used in the first year to identify infants born preterm at risk for delayed cognitive performance. Age-dependent HINE cut-off scores are proposed for detecting increased risk of delayed cognitive performance.