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High variability of individual longitudinal motor performance over five years in very preterm infants
Anjo J W M Janssen1, Rob A B Oostendorp2, Reinier P Akkermans2
1Radboud University Medical Center, Amalia Children's Hospital, Department of Rehabilitation, Pediatric Physical Therapy, Nijmegen, The Netherlands.
Insights
Motor skills in very preterm infants improve significantly from 6 months to 5 years. However, individual performance varies greatly, complicating clinical assessments of motor development in these children.
Area of Science:
- Pediatric neurology
- Developmental pediatrics
- Motor development research
Background:
- Very preterm (VPT) infants often exhibit motor delays.
- Understanding longitudinal motor development is crucial for early intervention.
- Previous studies have not fully captured the individual variability in motor trajectories.
Purpose of the Study:
- To assess longitudinal motor performance in very preterm infants from 6 months to 5 years.
- To analyze motor development patterns based on gender and gestational age.
- To examine individual-level motor performance trajectories.
Main Methods:
- Prospective longitudinal study of 201 very preterm infants without severe impairments.
- Motor skills assessed using the Bayley Scales of Infant Development (BSID-II-MS) at 6, 12, and 24 months.
- Movement Assessment Battery for Children (MABC-2-NL) used at 5 years.
Main Results:
- Significant improvement in motor performance z-scores from -1.46 at 6 months to -0.52 at 5 years.
- At 5 years, girls outperformed boys in manual dexterity and balance.
- High individual variability in motor performance was observed throughout the study period.
Conclusions:
- Longitudinal motor performance shows substantial improvement over five years in very preterm infants.
- The high variability in individual motor trajectories presents challenges for clinical evaluation and research.
- Further research is needed to understand and address the factors contributing to this variability.
Aim:
To determine longitudinal motor performance in very preterm (VPT) infants from 6 months to 5 years of age for the entire cohort of infants, according to gender and gestational age and at the individual level.
Method:
Single-center, prospective longitudinal study of 201 VPT infants (106 boys) without severe impairments.
Outcomes:
Motor performance was assessed with the Bayley Scales of Infant Development (BSID-II-MS: 6, 12, 24 months) and the Movement Assessment Battery for Children (MABC-2-NL: 5 years).
Results:
At 6, 12, and 24 months and then at 5 years, 77%, 80%, 48%, and 22% of the infants, respectively, showed delayed motor performance (<-1SD). At 5 years, girls performed significantly better than boys in manual dexterity and balance. MIXED MODEL ANALYSES: that examined interactions between time and gender and time and gestational age, revealed no significant interactions. The variance at child level was 29%. Linear mixed model analysis revealed that mean z-scores of -1.46 at 6 months of age declined significantly to -0.52 at 5 years. Individual longitudinal motor performance showed high variability.
Implications:
Longitudinal motor performance improved almost 1 SD over five years. However, the variability of individual longitudinal motor performance hampers evaluation in clinical care and research.
