Auditory attention at the onset of West syndrome: correlation with EEG patterns and visual function

Developmental profile at initial presentation in children with infantile spasms

AIM

To describe the baseline developmental profile and influence of clinical and demographic factors on the developmental skills of infants diagnosed with infantile spasms.

METHOD

Ninety-five infants (55 males, 40 females) newly diagnosed with infantile spasms were recruited for a cross-sectional, longitudinal study. All infants underwent Bayley Scales of Infant and Toddler Development assessments in the cognitive, receptive communication, expressive communication, and fine and gross motor developmental domains; they also underwent visual, auditory, and social behaviour assessments. Infants were categorized as 'early' (<6mo) or 'late' (≥6mo) presenters; if presented within 28 days, this was considered as 'early presentation', whereas a delay greater than 28 days was considered as a 'delay in presentation'. Antenatal, perinatal, and postnatal risk factors were identified.

RESULTS

Over 90% of infants showed impairment in all domains, with the majority having severe delay; 99% showed cognitive impairment. Delayed presentation was significantly associated with receptive communication delay (odds ratio [OR]=5.35; 95% confidence interval [CI]=1.05-27.32). Onset at 6 months or less influenced auditory (OR=2.8; 95% CI=1.16-6.8) and visual (OR=3.03; 95% CI=1.22-7.57) behaviours. Neonatal infections impacted both receptive (OR=1.12; 95% CI=1.04-1.2) and expressive communication (OR=1.08; 95% CI=1.02-1.14) delay. Neonatal seizures significantly influenced visual, auditory, and social impairments. Expressive communication and gross motor development shared common perinatal risk factors.

INTERPRETATION

Adverse developmental status at presentation, associated with delayed presentation and neonatal risk factors should alert clinicians to the surveillance of at-risk infants and seek out timely interventions.

WHAT THIS PAPER ADDS

Ninety per cent of infants showed impaired cognitive, communication, and motor skills at presentation. Visual, auditory, and social behaviour impairments were significantly associated with perinatal risks. Visual, auditory, and social behaviour impairments were significantly associated with neonatal seizures.

Neurodevelopmental evolution of West syndrome: a 2-year prospective study

OBJECTIVE

The aim of this study was to evaluate the epileptic and developmental evolution in infants with West syndrome.

METHODS

A prospective study of 21 infants was performed, with a follow-up at 2 years. Serial assessment included long-term EEG monitoring, visual and auditory evaluation and assessment of neurodevelopment.

RESULTS

Neurosensory and developmental impairments at the spasm onset were transitory in seven cases, including four cryptogenic forms. In all other cases, there was a progressive worsening in neurosensory and developmental impairments. The epileptic evolution was generally better: in 11 of the 16 infants without seizures at outcome, spasms had already disappeared by 2 months after disease onset. Statistic analysis of results showed a correlation between neurosensory impairment and development throughout the whole follow-up. In addition, visual function at T1 resulted significant predictor of developmental outcome. Among the epileptic features, disorganization of slow sleep was an unfavorable prognostic factor.

CONCLUSION

Some forms of West syndrome are confirmed to have a benign evolution: among them there are not only cryptogenic cases but also symptomatic ones without significant neurodevelopmental impairment. Abnormalities of sleep organization, expression of the pervasive epileptic disorder, seem to play a role in determining a developmental deterioration. Neurosensory impairment since the onset of the disease could be a relevant cause of the developmental disorder.