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Assessment and Evaluation of the High Risk Neonate: The NICU Network Neurobehavioral Scale
Published on: August 25, 2014
Motor assessment of cocaine/polydrug exposed infants at age 4 months
1Program in Physical Therapy, Northwestern University, Chicago, IL.
Insights
Cocaine-exposed infants show higher risks for motor dysfunction by 4 months of age, as assessed by the Movement Assessment of Infants (MAI). The MAI identified significant differences in muscle tone, reflexes, and movement in these infants compared to non-exposed infants.
Area of Science:
- Neonatal Development
- Pediatric Neurology
- Developmental Pediatrics
Background:
- Intrauterine drug exposure, particularly to cocaine and polydrugs, is a significant concern for infant neurodevelopment.
- Previous studies have yielded mixed results regarding the impact of prenatal drug exposure on early motor development.
- The Movement Assessment of Infants (MAI) is a validated tool for assessing motor dysfunction risk in infants at 4 months.
Purpose of the Study:
- To evaluate the efficacy of the Movement Assessment of Infants (MAI) in identifying motor dysfunction risks in cocaine/polydrug-exposed infants.
- To compare motor development outcomes between cocaine/polydrug-exposed and non-exposed infants at 4 months of age.
- To determine if the MAI can detect subtle motor deficits associated with prenatal drug exposure.
Main Methods:
- A cohort of 50 non-drug-exposed infants and 74 cocaine/polydrug-exposed infants were assessed using the Movement Assessment of Infants (MAI).
- MAI total and categorical risk scores were analyzed, focusing on muscle tone, primitive reflexes, and volitional movement.
- Infants were categorized into risk ranges: no risk (0-7), questionable risk (8-13), and high risk (>13).
Main Results:
- Cocaine/polydrug-exposed infants exhibited significantly higher total risk scores on the MAI compared to non-exposed infants (p < .0001).
- Significant differences were observed in muscle tone, primitive reflexes, and volitional movement categories, with exposed infants scoring poorer (p < .0001).
- The distribution of infants across risk categories was significantly different between the groups (p < .0001), with more exposed infants falling into higher risk categories.
Conclusions:
- The Movement Assessment of Infants (MAI) effectively differentiates motor dysfunction risk between cocaine/polydrug-exposed and non-exposed infants at 4 months.
- Prenatal cocaine/polydrug exposure is associated with poorer motor development outcomes, including deficits in muscle tone, reflexes, and volitional movement.
- The MAI serves as a valuable tool for early identification of infants at risk for motor dysfunction due to intrauterine drug exposure, facilitating timely intervention.
Abstract:
Fifty nondrug-exposed infants and 74 cocaine/polydrug-exposed infants were evaluated on the Movement Assessment of Infants (MAI). The test provides an assessment of risk for motor dysfunction at age 4 months. There was a significant difference in total risk scores between the two groups of infants with cocaine-exposed infants having higher total risk scores (p less than .0001). Categorical risk scores revealed significant differences between the infants in muscle tone, primitive reflexes, and volitional movement with cocaine-exposed infants scoring more poorly in each category (p less than .0001). The groups scored differently on 11 of the 49 MAI items in those categories. Placement of infants within previously established ranges of risk scores (0-7 = no risk; 8-13 questionable risk; greater than 13 = high risk) revealed a significant difference in distribution between the two groups (p less than .0001). Earlier studies of the effects of intrauterine drug exposure have not revealed significant differences in motor development. The MAI demonstrated differential assessments of risk for motor dysfunction between cocaine-exposed and nondrug-exposed infants.
