Endocrine Abstracts

Background: Congenital Hyperinsulinism (CHI) is a disease of severe hypoglycaemia due to insulin hypersecretion, that can be recognised either early or late in childhood. CHI is associated with adverse neurodevelopmental outcomes. The Vineland Adaptive Behaviour Scales Second Edition (VABS-II) is a parent-report measure of intellectual and developmental functioning, which could be used to screen children with CHI for impairments.

Aims: To investigate reliability of Vineland to screen developmental problems in CHI.

Methods: Vineland questionnaires were completed by parents in 64 CHI children of age >1.5 years for communication, daily living skills, social and motor skills domains. Total and domain scores were converted to standard deviation scores. The Vineland also includes assessment of problematic behaviours, including externalising, internalising and total maladaptive behaviour scores. Vineland was validated in cohort of 9 children with idiopathic ketotic hypoglycaemia (IKH) without neurological problems; repeat variability was assessed in 7 children with CHI.

Results: Most children in this cohort presented in the neonatal period (Early-CHI) but 16 (25%) children presented beyond one month of age (Late-CHI). As expected, Vineland scores were in the normal range in IKH (median (range) −0.33(−1.73,1.13). However in CHI, total Vineland scores were low [−0.46(−3.60,4.00] across all domains. All Vineland scores were similar on repetition (paired t-test P=0.18–0.95). Vineland scores were inversely correlated with age at presentation (P=0.024) and male gender (P=0.036) independently. Late-CHI male scores were lower than females [−1.40(−3.60,0.87) v 0.20(−1.07,1.27), P=0.014], with additional 6.5% gender effect on age at presentation (P=0.04). Vineland scores showed inverse correlation with the severity markers such as mutations in CHI genes (P=0.039) and response to diazoxide treatment (P=0.019). Total Vineland scores correlated with independently assessed developmental delay in at least one domain [Odds ratio (OR) (95% confidence intervals, CI) 0.52(0.38,0.73), P<0.001]. Total behaviour scores also correlated with developmental delay, mainly for internalising behaviours [OR (95%CI) 1.30(1.09,1.55), P=0.005].

Conclusions: The Vineland Adaptive Behaviour Scale is a reliable screening tool for maladaptive development and behaviour correlating with developmental delay in children with CHI. Male gender, later age at presentation and severity of disease are independent risk factors for lower Vineland scores correlating with a guarded prognosis.