Insulin-like growth factor-1 is associated with cognitive outcome in infantile spasms

The molecular mechanisms that lead to long-term consequences of infantile spasms (IS) are poorly understood. Insulin-like growth factor-1 (IGF-1) is regulated by insults that might be stressful to the brain, and is crucial for early brain development. The aim of the present study was to correlate cerebrospinal fluid (CSF) levels of IGF-1 with antecedent insults and cognitive outcome.

We studied CSF IGF-1 and the adrenocorticotropic hormone (ACTH) concentrations in infants with idiopathic IS (IIS), symptomatic IS (SIS), and controls.

Infants with IIS had CSF IGF-1 concentrations similar to those of the control children, but children with SIS had markedly low CSF IGF-1 concentrations. In addition, CSF ACTH concentrations were significantly lower in the children with SIS than in those with IIS. High CSF IGF-1 concentrations were associated with an idiopathic etiology, absence of early (pre- or perinatal) insults or stress, normal brain imaging studies, good response to ACTH therapy, and favorable cognitive outcome. Low CSF IGF-1 concentrations were associated with low CSF ACTH concentrations, a history of early insults or stress, cerebral atrophy, poor response to therapy, and poor cognitive outcome.

In children with IS, insults or stress in early life may affect the synthesis of IGF-1, which might play a role in the reduction of certain cognitive functions.