BASELINE COGNITIVE PERFORMANCE IN ASYMPTOMATIC BOYS WITH X-ALD WHO LATER DEVELOP CEREBRAL DISEASE

Objectives: Childhood Cerebral Phenotype of X- Linked Adrenoleukodystrophy is rapidly progressive and fatal without treatment. Neither genotype nor the biochemical abnormality can predict which patients will develop cerebral disease. Neurological symptoms usually follow MRI abnormality. However it is not clear if cognitive function abnormality precedes MRI abnormality. We did retrospective analyses of the cognitive performance in CERALD patients before they had first evidence of MRI abnormality and compared them with asymptomatic boys with X-ALD who did not develop CERALD.

Methods: Retrospective analyses of cognitive function were done in 57 boys with X-ALD when they are asymptomatic (10 had developed CERALD later, this group was called as “progressed”). Mean±SD age in years was 6.7±3.5 Neuropsychological tests included IQ evaluation [full scale (FSIQ), verbal (VIQ) and performance (PIQ)] and evaluation of 5 cognitive domains (language, visuospatial, perception, visuomotor/graphomotor, memory and attention/executive function). Standardized Z scores, relative to published age appropriate normative means was generated. Student's t test was used to compare cognitive performance between those who later progressed versus those who remained normal (non-progressed).

Results: 1) was 7±2.4 years. Mean age of developing MRI abnormality, (MRI LOES Score The progressed group demonstrated significantly lower baseline FSIQ, VIQ than the non-progressed group, (Z Score for FSIQ was –0.2±0.8 versus 0.4±0.9, p=0.05, and for VIQ was –0.49±0.97versus 0.18±0.9, p=0.04). There was no significant difference in performance on the remaining domains between progressed and non-progressed groups.

Conclusion: IQ measurements may be the first indicators of impending MRI abnormality. Ongoing follow-up in a larger cohort of patients will help establish the exact role of such specific cognitive markers in predicting conversion to CERALD phenotype enabling earlier detection for timely intervention.