Endocrine Abstracts

Previous research concerning the cognitive profile of children with CHI has identified a high incidence of significant learning difficulty (Rother et al. 2001, Jack et al. 2003). Both studies report an incidence of 30 to 50% cognitive skills within the learning disability range in both study populations. Furthermore, Rother et al. (2001) suggested that all children investigated demonstrated some form of cognitive difficulty, ranging from learning disability to subtle attentional problems. More recent research has suggested that satisfactory neurocognitive outcomes are possible in conservatively treated children with CHI (Mazer-Aronovitch et al. 2007). However, in this population some 29% were also noted to have learning difficulties. The current study performed a detailed analysis of the cognitive profile of children with CHI, to identify whether a British sample corresponded with findings from other population studies.

Methods: All CHI patients over 6 years of age known to the Northern Congenital Hyperinsulinism Service (NorCHI) were invited to attend a neuropsychological assessment. Fifteen children were identified, of which 9 have completed the assessment to date. All children completed the Wechsler Intelligence Scale for Children – 4th edition (WISC-IV), the Test of Everyday Attention – child version (TEA-Ch) and some subtests from the Wechsler Individual Achievement Test – 2nd edition (WIAT-II).

Results: Of the nine children assessed six children showed index and achievement scores in the average to above average ranges (mean Verbal Comprehension Index (VCI) −106, mean Word Reading Standard Score −114). However 4/6 showed deficits in sustained attention achieving scores at 1st centile; 1/6 showed a relative weakness in sustained attention (12th centile) and 1/6 showed difficulties with switching and selective attention (3rd centile). Three children showed wider cognitive impairment (mean VCI −60, Mean Word Reading Standard Score −77); All achieved sustained attention scores at 1st centile.

Conclusions: Children with apparently ‘normal’ educational achievements and presentation can show subtle cognitive difficulty in the selective and sustained attentional domains. Furthermore, there is a growing body of evidence that children with apparently stable CHI can show cognitive difficulty at levels higher than expected in the general population. This has implications for clinical practice, with clinicians being reminded to investigate academic achievement more carefully, with particular focus on attentional abilities.