Motor outcome at the age of one after perinatal hypoxic-ischemic encephalopathy

The Polish Version of the Alberta Infant Motor Scale: Cultural Adaptation and Validation

The Alberta Infant Motor Scale (AIMS) is a diagnostic tool for the assessment of the motor performance of infants from the time of birth, to the period of independent walking (0-18 months). This study aims to derive a Polish version of the AIMS through its cultural adaptation and validation. The study included 145 infants aged 0-18 months, who were divided into four further age groups: 0-3 months, 4-7 months, 8-11 months, and older than 12 months. The validation was based on an analysis of intrarater and interrater reliability values, as well as concurrent validity, using the gross motor scale of Peabody Developmental Motor Scales-2 (PDMS-2). The total Intraclass Correlation Coefficient (ICC) for intrarater reliability was 0.99 (ICC range in positions was 0.87-0.99, in subgroups was 0.91-0.99), while in particular positions, the ICC ranges were as follows: prone 0.97-0.99, supine 0.94-0.99, sitting 0.95-0.99, and standing: 0.63-0.99. The total ICC for interrater reliability was 0.99 (ICC range in positions was 0.98-0.99, in subgroups was 0.91-0.99), while in particular positions, the ICC ranges were as follows: prone 0.95-0.99, supine 0.93-0.96, sitting 0.93-0.98, standing 0.91-0.98. Only the standing position was analyzed for the subgroup of participants over 12 months old. The Spearman correlation between the Polish version of the AIMS and the gross motor scale of PDMS-2 was significant in the total population (r = 0.97, p < 0.0001) and in subgroups (r = 0.79-0.85, p < 0.0001). The results of our study confirm that the Polish version of the AIMS is reliable for infants aged 0-18 months and can be applied to this population for clinical and scientific purposes.

Trial Registry

ClinicalTrials.gov ID NCT05264064, URL https://clinicaltrials.gov/ ct2/show/NCT05264064.

Volume reduction of caudate nucleus is associated with movement coordination deficits in patients with hippocampal atrophy due to perinatal hypoxia-ischaemia

Acute sentinel hypoxia-ischaemia in neonates can target the hippocampus, mammillary bodies, thalamus, and the basal ganglia. Our previous work with paediatric patients with a history of hypoxia-ischaemia has revealed hippocampal and diencephalic damage that impacts cognitive memory. However, the structural and functional status of other brain regions vulnerable to hypoxia-ischaemia, such as the basal ganglia, has not been investigated in these patients. Furthermore, it is not known whether there are any behavioural sequelae of such damage, especially in patients with no diagnosis of neurological disorder. Based on the established role of the basal ganglia and the thalamus in movement coordination, we studied manual motor function in 20 participants exposed to neonatal hypoxia-ischaemia, and a group of 17 healthy controls of comparable age. The patients' handwriting speed and accuracy was within the normal range (Detailed Assessment of Speed of Handwriting), and their movement adaptation learning (Rotary Pursuit task) was comparable to the control group's performance. However, as a group, patients showed an impairment in the Grooved Pegboard task and a trend for impairment in speed of movement while performing the Rotary Pursuit task, suggesting that some patients have subtle deficits in fine, complex hand movements. Voxel-based morphometry and volumetry showed bilateral reduction in grey matter volume of the thalamus and caudate nucleus. Reduced volumes in the caudate nucleus correlated across patients with performance on the Grooved Pegboard task. In summary, the fine movement coordination deficit affecting the hand and the wrist in patients exposed to early hypoxic-ischaemic brain injury may be related to reduced volumes of the caudate nucleus, and consistent with anecdotal parental reports of clumsiness and coordination difficulties in this cohort.

Clinical characteristics predicting abnormal brain magnetic resonance image findings in hypoxic-ischemic encephalopathy infants

BACKGROUND

The aim of this study was to elucidate the specific clinical characteristics associated with abnormal brain magnetic resonance image (MRI) findings in hypoxic ischemic encephalopathy (HIE) infants in order to discern how to predict poorer outcomes more accurately.

METHODS

A retrospective data analysis of HIE infants admitted to the neonatal intensive care unit of a tertiary hospital was performed. Baseline perinatal information and physical and neurological findings were compared in HIE infants according to the presence of abnormal brain MRI findings.

RESULTS

A total of 69 infants were enrolled in the study. Of these, 48(69.6%) infants received therapeutic hypothermia, and 60(87.0%) infants presented abnormal findings on brain MRI. Decreased muscle tone and lower Apgar scores were more often observed in infants with abnormal MRI results(P<0.05). The presence of hypotonia and 1- and 5-minute Apgar scores equal to or less than the yielded cut-off values (5.5 and 7.5, respectively)were associated with a 7.23-, 9.14-, 9.78-fold increased risk of having abnormal brain MRI results.

CONCLUSIONS

As muscle tone and Apgar scores were associated with abnormal brain MRI findings in HIE infants, these clinical characteristics may serve as early indicators of poor neurodevelopmental outcomes and signal the need for special attention and in-depth follow-up by MRI.

Alberta Infant Motor Scale (AIMS) Performance of Greek Preterm Infants: Comparisons With Full-Term Infants of the Same Nationality and Impact of Prematurity-Related Morbidity Factors

BACKGROUND

Only a few studies have been conducted with the objective of creating norms of the Alberta Infant Motor Scale (AIMS) for the assessment of gross motor development of preterm infants. The AIMS performance of preterm infants has been compared with that of the Canadian norms of full-term infants, but not with that of full-term infants of the same nationality. Moreover, the possible impact of prematurity-related morbidity factors on AIMS performance is unknown.

OBJECTIVES

The aims of this study were: (1) to evaluate AIMS trajectory in a large population of Greek preterm infants and create norms, (2) to compare it with the AIMS trajectory of Greek full-term infants, and (3) to examine the possible influence of neonatal morbidity on AIMS scores in the preterm sample.

DESIGN

This was a cross-sectional study.

METHODS

Mean AIMS scores were compared, per month (1-19), between 403 preterm infants (≤32 weeks of age, corrected for prematurity) and 1,038 full-term infants. In preterm infants, the association of AIMS scores with respiratory distress syndrome (RDS), intraventricular hemorrhage (IVH) of grade ≤III, bronchopulmonary dysplasia (BPD), retinopathy of prematurity (ROP), and sepsis was assessed by hierarchical regression analysis.

RESULTS

Alberta Infant Motor Scale scores were significantly lower in preterm infants than in full-term infants. Mean AIMS scores in preterm infants were significantly associated with RDS (b=-1.93; 95% CI=-2.70, -1.16), IVH (b=-0.97; 95% CI=-1.69, -0.25), and ROP (b=-1.12; 95% CI=-1.99, -0.24) but not with BPD or sepsis in hierarchical regression analysis.

CONCLUSIONS

Alberta Infant Motor Scale norms were created for Greek preterm infants. This study confirms that AIMS trajectories of preterm infants are below those of full-term infants of the same nationality. The influence of morbidity factors, including RDS, IVH, and ROP, should be taken into account when administering the AIMS in preterm infants.

Long-term motor and behavioral outcome after perinatal hypoxic-ischemic encephalopathy

BACKGROUND

A cohort of children born with perinatal hypoxic-ischemic encephalopathy (HIE) was followed prospectively until school age.

AIMS

To describe motor outcome and behavioral functioning of school-age children after perinatal HIE and the relationship with neonatal MRI and outcome at age 2.

METHODS

Twenty-five children (19 males), born at term with perinatal HIE, were assessed at a mean age of 7 y 6 m (range 6 y 4 m-8 y 2 m). Motor ability was assessed with the Movement Assessment Battery for Children (2nd version) and behavioral functioning was assessed with the Child Behavior Checklist. Neonatal MRI was scored according to Barkovich classification.

RESULTS

Of the 25 included children, eight had cerebral palsy (CP). Of the 17 children without CP, nine had impaired motor ability (of which 3 scored definitely abnormal), and four had behavioral problems. There was a significant difference in motor performance (p = 0.008) between children with normal and children with abnormal neonatal MRI. Two (of four) children with normal motor ability and seven (of 14) children with normal neurological examination at age 2 showed impaired motor ability at school age.

CONCLUSIONS

Half of the children without CP had impaired motor ability at school age. A normal outcome after HIE at young age does not necessarily imply a good outcome at school age, even when neonatal MRI does not show any abnormalities. More research is needed on the behavioral and cognitive consequences of HIE at school age and on the consequences for quality of life for children with and without CP.

Gross motor development in full-term Greek infants assessed by the Alberta Infant Motor Scale: reference values and socioeconomic impact

OBJECTIVE

The aims of this study were to investigate gross motor development in Greek infants and establish AIMS percentile curves and to examine possible association of AIMS scores with socioeconomic parameters.

METHODS

Mean AIMS scores of 1068 healthy Greek full-term infants were compared at monthly age level with the respective mean scores of the Canadian normative sample. In a subgroup of 345 study participants, parents provided, via interview, information about family socioeconomic status. Multiple linear regression analysis was performed to evaluate the relationship of infant motor development with socioeconomic parameters.

RESULTS

Mean AIMS scores did not differ significantly between Greek and Canadian infants in any of the 19 monthly levels of age. In multiple linear regression analysis, the educational level of the mother and also whether the infant was being raised by grandparents/babysitter were significantly associated with gross motor development (p=0.02 and p<0.001, respectively), whereas there was no significant correlation of mean AIMS scores with gender, birth order, maternal age, paternal educational level and family monthly income.

CONCLUSIONS

Gross motor development of healthy Greek full-term infants, assessed by AIMS during the first 19months of age, follows a similar course to that of the original Canadian sample. Specific socioeconomic factors are associated with the infants' motor development.

Motor and cognitive assessment of infants and young boys with Duchenne Muscular Dystrophy: results from the Muscular Dystrophy Association DMD Clinical Research Network

Therapeutic trials in Duchenne Muscular Dystrophy (DMD) exclude young boys because traditional outcome measures rely on cooperation. The Bayley III Scales of Infant and Toddler Development (Bayley III) have been validated in developing children and those with developmental disorders but have not been studied in DMD. Expanded Hammersmith Functional Motor Scale (HFMSE) and North Star Ambulatory Assessment (NSAA) may also be useful in this young DMD population. Clinical evaluators from the MDA-DMD Clinical Research Network were trained in these assessment tools. Infants and boys with DMD (n = 24; 1.9 ± 0.7 years) were assessed. The mean Bayley III motor composite score was low (82.8 ± 8; p ≤ .0001) (normal = 100 ± 15). Mean gross motor and fine motor function scaled scores were low (both p ≤ .0001). The mean cognitive comprehensive (p=.0002), receptive language (p ≤ .0001), and expressive language (p = .0001) were also low compared to normal children. Age was negatively associated with Bayley III gross motor (r = -0.44; p = .02) but not with fine motor, cognitive, or language scores. HFMSE (n=23) showed a mean score of 31 ± 13. NSAA (n = 18 boys; 2.2 ± 0.4 years) showed a mean score of 12 ± 5. Outcome assessments of young boys with DMD are feasible and in this multicenter study were best demonstrated using the Bayley III.

Delta-opioid receptor activation prolongs respiratory motor output during oxygen-glucose deprivation in neonatal rat spinal cord in vitro

Delta opioid receptor (DOR) activation protects the adult mammalian brain during oxygen-glucose deprivation (OGD), but it is not known whether neonatal spinal motor circuits are also protected. Also, it is unclear whether the timing of spinal DOR activation relative to spinal OGD is important for neuroprotection. Thus, a split-bath in vitro neonatal rat brainstem/spinal cord preparation was used to record spontaneous respiratory motor output from cervical (C4-C5) and thoracic (T5-T6) ventral spinal roots while exposing only the spinal cord to OGD solution (0 mM glucose, bubbled with 95% N(2)/5% CO(2)) or DOR agonist drugs (DADLE, DPDPE). Spinal OGD solution application caused respiratory motor output frequency and amplitude to decrease until all activity was abolished (i.e. end-point times) after 25.9±1.4 min (cervical) and 25.2±1.4 min (thoracic). Spinal DOR activation via DPDPE (1.0 μM) prior-to and during spinal OGD increased cervical and thoracic end-point times to 35-48 min. Spinal DADLE or DPDPE (1.0 μM) application 15 min following spinal OGD onset increased cervical and thoracic end-point times to 36-45 min. Brief spinal DPDPE (1.0 μM) application for 10 min at 25 min before spinal OGD onset increased cervical and thoracic end-point times to 41-46 min. Overall, the selective DOR agonist, DPDPE, was more effective at increasing end-point times than DADLE. Naltrindole (DOR antagonist; 10 μM) pretreatment blocked DPDPE-dependent increase in end-point times, suggesting that DOR activation was required. Spinal naloxone (1.0 μM) application before and during spinal OGD also increased end-point times to 31-33 min, but end-point times were not altered by Mu opioid receptor (MOR) activation or DOR activation/MOR blockade, indicating that there are complex interactions between OGD and opioid signaling pathways. These data suggest DOR activation before, during, and after spinal OGD protects central motor networks and may provide neuroprotection during unpredictable perinatal ischemic events.

MRI and withdrawal of life support from newborn infants with hypoxic-ischemic encephalopathy

The majority of deaths in infants with hypoxic-ischemic encephalopathy (HIE) follow decisions to withdraw life-sustaining treatment. Clinicians use prognostic tests including MRI to help determine prognosis and decide whether to consider treatment withdrawal. A recently published meta-analysis provided valuable information on the prognostic utility of magnetic resonance (MR) biomarkers in HIE and suggested, in particular, that proton MR spectroscopy is the most accurate predictor of neurodevelopmental outcome. How should this evidence influence treatment-limitation decisions? In this article I outline serious limitations in existing prognostic studies of HIE, including small sample size, selection bias, vague and overly inclusive outcome assessment, and potential self-fulfilling prophecies. Such limitations make it difficult to answer the most important prognostic question. Reanalysis of published data reveals that severe abnormalities on conventional MRI in the first week have a sensitivity of 71% (95% confidence interval: 59%-91%) and specificity of 84% (95% confidence interval: 68%-93%) for very adverse outcome in infants with moderate encephalopathy. On current evidence, MR biomarkers alone are not sufficiently accurate to direct treatment-limitation decisions. Although there may be a role for using MRI or MR spectroscopy in combination with other prognostic markers to identify infants with very adverse outcome, it is not possible from meta-analysis to define this group clearly. There is an urgent need for improved prognostic research into HIE.

Protecting motor networks during perinatal ischemia: the case for delta-opioid receptors

Perinatal ischemia is a common clinical problem with few successful therapies to prevent neuronal damage. Delta opioid receptor (DOR) activation is a versatile, evolutionarily conserved, endogenous neuroprotective mechanism that blocks several steps in the deleterious cascade of neurological events during ischemia. DOR activation prior to ischemia or severe hypoxia is neuroprotective in spinal motor networks, as well as cortical, cerebellar, and hippocampal neural networks. In addition to providing acute and long-lasting neuroprotection against ischemia, DOR activation appears to provide neuroprotection when given before, during, or following the onset of ischemia. Finally, DORs can be upregulated by several physiological and experimental perturbations. Potential adverse side effects affecting motor control, such as respiratory depression and seizures, are not well established in young mammals and may be mitigated by altering drug choice and method of drug administration. The unique features of DOR-dependent neuroprotection make it an attractive potential therapy that may be given to at-risk pregnant mothers shortly before delivery to provide long-lasting neuroprotection against unpredictable perinatal ischemic events.

Standardization of the Alberta infant motor scale in full-term Greek infants: Preliminary results

BACKGROUND

The Alberta Infant Motor Scale (AIMS) is a norm-referenced test that assesses the spontaneous motor performance of infants from birth through independent walking (0-18 months). This scale has been utilized for clinical and research purposes in various countries, however, whether the initial standardization in Canadian infants is also representative of other countries' populations has been questioned.

AIM

To assess whether the AIMS needs new reference values for Greek infants.

METHODS

A cohort of 424 healthy full-term infants (250 boys and 174 girls), aged between 7 days and 18 months, derived from various areas of the Prefecture of Attica and from all socio-economic classes to ensure a true representation, was studied. The AIMS-scores of Greek infants were compared with the norm-referenced values of the original Canadian population reported by Piper and Darrah.

RESULTS

The mean AIMS-scores did not differ significantly between Greek and Canadian infants at any age level from birth to 18 months, except for the 2-<3 month of age when higher scores were observed in Greek infants (p=0.02). There was no significant difference in AIMS-values corresponding to the 5th and 90th percentile between Greek and Canadian infants. Inter-rater reliability was excellent in our study population [ICC: 0.99 (95% CI: 0.99-0.99)].

CONCLUSION

In healthy full-term Greek infants, gross motor maturity assessed by the AIMS during the first 18 months of age, seems to follow a similar course to that of Canadian infants.

Cerebral magnetic resonance biomarkers in neonatal encephalopathy: a meta-analysis

OBJECTIVE

Accurate prediction of neurodevelopmental outcome in neonatal encephalopathy (NE) is important for clinical management and to evaluate neuroprotective therapies. We undertook a meta-analysis of the prognostic accuracy of cerebral magnetic resonance (MR) biomarkers in infants with neonatal encephalopathy.

METHODS

We reviewed all studies that compared an MR biomarker performed during the neonatal period with neurodevelopmental outcome at > or =1 year. We followed standard methods recommended by the Cochrane Diagnostic Accuracy Method group and used a random-effects model for meta-analysis. Summary receiver operating characteristic curves and forest plots of each MR biomarker were calculated. chi(2) tests examined heterogeneity.

RESULTS

Thirty-two studies (860 infants with NE) were included in the meta-analysis. For predicting adverse outcome, conventional MRI during the neonatal period (days 1-30) had a pooled sensitivity of 91% (95% confidence interval [CI]: 87%-94%) and specificity of 51% (95% CI: 45%-58%). Late MRI (days 8-30) had higher sensitivity but lower specificity than early MRI (days 1-7). Proton MR spectroscopy deep gray matter lactate/N-acetyl aspartate (Lac/NAA) peak-area ratio (days 1-30) had 82% overall pooled sensitivity (95% CI: 74%-89%) and 95% specificity (95% CI: 88%-99%). On common study analysis, Lac/NAA had better diagnostic accuracy than conventional MRI performed at any time during neonatal period. The discriminatory powers of the posterior limb of internal capsule sign and brain-water apparent diffusion coefficient were poor.

CONCLUSIONS

Deep gray matter Lac/NAA is the most accurate quantitative MR biomarker within the neonatal period for prediction of neurodevelopmental outcome after NE. Lac/NAA may be useful in early clinical management decisions and counseling parents and as a surrogate end point in clinical trials that evaluate novel neuroprotective therapies.

Motor testing at 1 year improves the prediction of motor and mental outcome at 2 years after perinatal hypoxic-ischaemic encephalopathy

AIM

To investigate the predictive value of motor testing at 1 year for motor and mental outcome at 2 years after perinatal hypoxic-ischaemic encephalopathy (HIE) in term neonates.

METHOD

Motor and mental outcome at 2 years was assessed with the Bayley Scales of Infant Development, 2nd edition (BSID-II) in 32 surviving children (20 males, 12 females; mean gestational age 40.2 wk, SD 1.4; mean birthweight 3217g, SD 435) participating in a prospective cohort study of HIE. The predictive value of three motor tests (Alberta Infant Motor Scale [AIMS], BSID-II, and the Neurological Optimality Score [NOS]) at 1 year was analysed, in addition to predictions based on neonatal Sarnat staging and magnetic resonance imaging (MRI). Poor motor test results were defined as an AIMS z-score of <-2, a psychomotor developmental index of the BSID-II of <70, or a NOS of <26. Poor motor and poor mental outcome at 2 years was defined as a psychomotor developmental index or mental developmental index of the BSID-II of <70.

RESULTS

Twelve children, all with Sarnat grade II, had a poor motor outcome and 12 children, of whom one had Sarnat grade I, had a poor mental outcome at 2 years. Nine children had cerebral palsy, of whom five had quadriplegia, three had dyskinesia, and one had hemiplegia. Poor motor tests at 1 year increased the probability of a poor motor outcome from 71% (range 92 to 100%), and a poor mental outcome from 59% (range 77 to 100%) in children with Sarnat grade II and abnormal MRI, assessed with the AIMS and BSID-II or NOS respectively.

INTERPRETATION

Additional motor testing at 1 year improves the prediction of motor and mental outcome at 2 years in children with Sarnat grade II and abnormal MRI.

A review of developmental outcomes of term infants with post-asphyxia neonatal encephalopathy

BACKGROUND/AIMS

Post-asphyxia neonatal encephalopathy (NE) is one of the main causes of disabilities in term-born infants. This review attempted to investigate the developmental outcomes of term-born infants with post-asphyxia NE.

METHOD

An electronic search on various databases identified 13 empirical studies against the selection criteria modified from the consensus statement from the International Cerebral Palsy Task Force.

RESULTS

The overall quality of methodology of these studies was average. The random effect meta-estimate of the proportion of infants having adverse developmental outcomes such as death, cognitive impairment, sensory-motor impairments was 47% (95% CI 36-57%). Significant heterogeneity (I(2)=87.7%, p<0.00001) between studies indicated variations in number of subjects in studies and their characteristics. For those studies using the Sarnat grading of NE, the proportion of infants with adverse outcomes was nil in stage 1 (mild) NE, 32% in stage 2 (moderate) and almost 100% in stage 3 (severe) NE.

CONCLUSIONS

At present, researchers are using very loose diagnostic criteria of perinatal asphyxia and post-asphyxia NE, making the study samples heterogeneous. Clinicians and researchers are urged to make use of the recent consensus statement regarding diagnostic criteria for intrapartum asphyxia and to identify these high-risk infants for early intervention.

Is there a way to predict outcome in (near) term neonates with hypoxic-ischemic encephalopathy based on MR imaging?

BACKGROUND AND PURPOSE

It has previously been demonstrated that comparison of signal intensity (SI) between selected brain structures on T1-weighted images enables distinction between the absence or presence of hypoxic-ischemic (HI) brain injury in young infants. The aim of the present study was to assess whether this method of brain structure T1-weighted SI comparison also enables prediction of outcome.

MATERIALS AND METHODS

Survivors of a group of 57 children with neonatal HI encephalopathy (HIE) grade 2 or 3 according to Sarnat and Sarnat and controls who underwent neonatal MR imaging were retrospectively assigned to 1 of 3 outcome groups at 5 years of age, depending on developmental outcome: 1) normal, 2) mildly abnormal, and 3) definitely abnormal. Gestational age was not significantly different between the HIE group (range, 35 + 5-42 + 5 weeks; mean, 39 + 4 weeks) and control group (range, 35 + 0-42 + 1 weeks; mean, 39 + 2 weeks). We calculated the predictive values of the neonatal clinical HIE classification according to Sarnat and Sarnat for outcome (neonatal death and developmental outcome in survivors). We assessed which brain structure T1-weighted SI comparison scored best for outcome prediction. Predictive values of that comparison for outcome were calculated for the entire group and for the HIE grade 2 group only, a patient group with highly variable outcome.

RESULTS

Of the 57 children, 6 died. Outcome group 1 consisted of 31; group 2, of 14; and group 3, of 6 children. The positive predictive value of the neonatal clinical classification for adverse outcome (outcome group 3 and death) was 52%; and negative predictive value, 100%. These were respectively 45% and 0% in children with HIE grade 2. Of all brain structure T1-weighted SI comparisons, that of the posterior limb of the internal capsule versus the posterolateral putamen scored best for outcome prediction. The positive predictive value for adverse outcome was 69%; and negative predictive value, 98%. In children with HIE grade 2, the positive predictive value and negative predictive value for adverse outcome were 67% and 88%.

CONCLUSIONS

Brain structure T1-weighted SI comparisons are helpful to predict outcome in (near) term neonates with HIE. This finding adds to the current knowledge and clinical practice. If the SI in the posterolateral putamen is less than the SI in the posterior limb of the internal capsule, favorable outcome is very likely, whereas if the SI in the posterolateral putamen is equal to or greater than the SI in the posterior limb of the internal capsule, adverse outcome is very likely. In neonates with HIE grade 2 according to Sarnat and Sarnat, prediction of outcome is substantially improved by using these brain structure T1-weighted SI comparisons.