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Assessment and Evaluation of the High Risk Neonate: The NICU Network Neurobehavioral Scale
Published on: August 25, 2014
Sequential neuromotor examination in children with intrauterine cocaine/polydrug exposure
H M Belcher1, B K Shapiro, M Leppert
1The Kennedy Krieger Institute, Baltimore, MD 21205, USA.
Insights
Infants exposed to drugs in utero often show temporary neuromotor issues, but persistent leg-extensor tone and delayed motor skills like walking are common, especially with combined cocaine and opiate exposure.
Area of Science:
- Neurodevelopmental Pediatrics
- Neonatal Toxicology
- Developmental Psychology
Background:
- Intrauterine drug exposure impacts infant neurodevelopment.
- Longitudinal data on neurodevelopmental outcomes in drug-exposed infants are crucial.
- Understanding the evolution of tone abnormalities is key for early intervention.
Purpose of the Study:
- To track the neurodevelopmental status of drug-exposed infants longitudinally.
- To characterize the progression of early tone abnormalities.
- To correlate neuromotor outcomes with specific drug exposure patterns.
Main Methods:
- A randomized trial followed 157 drug-exposed newborns.
- Infants were assessed at 3, 6, and 12 months using a sequential neuromotor examination.
- Infants were categorized by maternal drug use and neonatal drug screen results.
Main Results:
- Most neonatal neuromotor abnormalities resolved by 12 months.
- Axial hypotonia was common neonatally but rare at 12 months.
- Combined cocaine and opiate exposure was linked to abnormal neuromotor exams and peripheral hypertonia, with persistent leg-extensor tone in 67% of abnormal 12-month exams. Rolling and walking were delayed.
Conclusions:
- While many neonatal neuromotor issues resolve, persistent tone abnormalities and developmental delays are significant concerns in drug-exposed infants.
- Specific drug exposure patterns, particularly combined cocaine and opiate use, are associated with poorer neuromotor outcomes.
- Early identification and intervention are vital for improving long-term neurodevelopmental trajectories.
Abstract:
Data are presented on 157 newborn infants followed sequentially in a randomized home-based nursing-intervention trial for drug-exposed infants with follow up at 3 (N=118), 6 (N=124), and 12 months (N=77). The objectives of this study were to describe the longitudinal neurodevelopmental status of a cohort of children with intrauterine exposure to illicit drugs during their gestation, characterize the evolution of early tone abnormalities in a polydrug-exposed cohort, and determine whether neuromotor outcome is associated with drug-exposure patterns. For analysis, infants were grouped based on maternal drug-use pattern and the presence of drug metabolites in the neonatal drug screen. The sequential neuromotor examination was used at each age to define the neuromotor status of six domains and define categorical classifications as either normal, suspect, or abnormal. Multiple patterns of neuromotor abnormalities were observed during the neonatal period; most resolved over time. Axial hypotonia was a prominent finding in the neonatal period; however, it was infrequent in abnormal examinations at 12 months. Increased lower-extremity tone was a less frequent finding during the neonatal period. Infants whose neonatal urine drug screen was positive for both cocaine and opiates, were more likely than infants with negative urine drug screens, cocaine only, or opiate only drug screen results to have abnormal neuromotor examinations; while positive maternal drug screens for concurrent cocaine and opiate use were associated with peripheral hypertonia. Persistence of increased leg-extensor tone was found in 67% of the abnormal examinations at 12 months. Acquisition of rolling and walking was delayed in the drug-exposed cohort.
