Developmental Language Disorder: Wake and Sleep Epileptiform Discharges and Co-morbid Neurodevelopmental Disorders

Area of Science:

• Neuroscience
• Developmental Pediatrics
• Clinical Neurology

Background:

• Developmental language disorder (DLD) often co-occurs with other developmental conditions, potentially causing long-term challenges.
• Understanding DLD subgroups, their causes, and associated conditions is crucial for effective intervention.

Purpose of the Study:

• To characterize subgroups of children with DLD.
• To investigate etiological factors and clinical comorbidities in DLD.
• To examine the role of epileptiform discharges during wakefulness and sleep in DLD.

Main Methods:

• Retrospective study of 55 children (mean age 6.2 years) with DLD.
• Phoniatric, psychologic, neurologic, and electroencephalography (EEG)/polysomnography (PSG) assessments.
• Analysis of receptive vs. expressive DLD, perinatal factors, comorbidities, and EEG/PSG findings.

Main Results:

• Receptive DLD (63%) showed significantly poorer phonemic hearing than expressive DLD (37%).
• High rates of perinatal risk factors (50.9%) and comorbidities like motor coordination disorder (61.1%) and ADHD (70.9%) were observed.
• Epileptiform discharges were present in 36.4% on wake EEG and increased to 55.6% during nocturnal PSG (p=0.01), predominantly in NREM sleep.

Conclusions:

• DLD is closely associated with perinatal risk factors and neurodevelopmental disorders.
• Epileptiform discharges are more prevalent during sleep in children with DLD, with altered spatial distribution compared to wakefulness.