Cognitive Profiles and Brain Volume Are Affected in Patients with Silver-Russell Syndrome

Context: There is little information on cognitive function in Silver-Russell syndrome (SRS), and no neuroimaging studies are available so far.

Objective: To assess cognitive function and brain volumes in patients with SRS.

Design/setting: Wechsler Intelligence Scale and brain magnetic resonance on a 3-Tesla scanner with Voxel-based morphometry analysis were performed between 2016 and 2018 in a single tertiary university center.

Partecipants: 38 white subjects with clinical diagnosis of SRS confirmed by molecular analysis: 30 of these patients (mean age 12.6 ± 10 years) were enrolled for cognitive assessment; 23 of the 30 performed neuroimaging sequences. A control group of 33 school-aged children performed cognitive assessment while 65 age and sex-matched volunteers were included for the neuroradiological assessment.

Main outcomes: Intelligence quotient, Verbal Comprehension Index (VCI), Perceptual Reasoning Index (PRI), Working Memory Index (WMI), Processing Speed Index, and brain volume.

Results: The mean overall IQ score was 87.2 ± 17, and it was significantly lower in the maternal uniparental disomy of chromosome 7 (mUPD7) group at the age of 6 to 16 years compared to loss of methylation on chromosome 11p15 (11p15 LOM) group and to controls. VCI, PRI, and WMI were significantly higher in 11p15 LOM group and in control group than in mUPD7 group at the age of 6 to 16 years. There were no significant differences in cognitive scores between 11p15 LOM school-aged patients and the control group. SRS patients showed lower brain volume compared to controls at the frontal/temporal poles and globi pallidi.

Conclusions: Patients with mUPD7 had an impaired cognitive profile. The brain volume at the frontal/temporal lobes and at the globi pallidi was reduced in patients with SRS.