Congenital anomalies in children with postneonatally acquired cerebral palsy: an international data linkage study

Cerebral palsy characteristics in term-born children with and without detectable perinatal risk factors: A cross-sectional study

AIM

To compare, in term-born children with cerebral palsy (CP), the characteristics of those who exhibit detectable risk factors for CP at birth with those who do not.

METHOD

This was a cross-sectional study of term-born children using the Canadian Cerebral Palsy Registry comparing those with and without perinatal risk factors and/or neonatal symptoms for pregnancy, birth and neonatal characteristics, magnetic resonance imaging (MRI) findings, CP subtype, and impairment severity. Risk factors were quantified with a CP risk calculator. Multivariable and multinomial regressions were expressed as odds ratios (OR) and relative risk ratios.

RESULTS

Of 1333 term-born children, 781 (58.6%) had complete variables for the CP risk calculator, of whom 195 (25%) had 'undetectable' newborn infant CP risk, and they did not have greater postneonatal brain injury. Focal injury on MRI was more common (OR 2.0, 95% confidence interval [CI] 1.3-3.1) than in the 'detectable' group. The 'undetectable' group had more unilateral CP (OR 1.8, 95% CI 1.3-2.6), less severe motor impairment (OR 0.76, 95% CI 0.67-0.86), and were more verbal (OR 2.3, 95% CI 1.5-3.6).

INTERPRETATION

In the Canadian CP Registry, one-quarter of term-born children lacked neonatal encephalopathy, seizures, or perinatal risk factors. They were more likely to have unilateral CP, focal MRI findings, and communicate with words than children with risk factors or neonatal symptoms.

Cause-Specific Secular Trends and Prevention Measures of Post-Neonatally Acquired Cerebral Palsy in Victoria and Western Australia 1975-2014: A Population-Based Observational Study

AIM

To describe the timing and causes of post-neonatally acquired cerebral palsy (PNN-CP) and map the implementation of relevant preventive strategies against cause-specific temporal trends in prevalence.

METHODS

Data for a 1975-2014 birth cohort of children with PNN-CP (brain injury between 28 days and 2 years of age) were drawn from the Victorian and Western Australian CP Registers. Descriptive statistics were used to report causal events and timing. Poisson regression models were used to investigate the strength of evidence for cause-specific temporal trends in prevalence. Preventive strategies were mapped alongside cause-specific trends.

RESULTS

Amongst 512 children, causes of PNN-CP included infections (31%, n = 157), head injuries (24%, n = 121) and cerebrovascular accidents (CVAs) (23%, n = 119). Infections were the only main causal group of PNN-CP that declined significantly (p = 0.014). Fifty two percent (n = 267) of the PNN-CP cohort acquired their brain injury before 6 months of age, the majority having an infectious cause (57%, n = 90). Improved clinical care and a range of preventive strategies, including childhood vaccination programs, occurred during this period.

CONCLUSION

Infants under 6 months are a priority group for preventive strategies for PNN-CP. Declining temporal trends were observed for PNN-CP caused by infection, and the causal subgroup of CVAs associated with surgery. Interventions aimed at further reducing the risk of head injury, CVAs and infections, are needed to reduce the prevalence of PNN-CP.

Postneonatal Cerebral Palsy in Europe: Prevalence and Clinical Characteristics According to Contributory Events: An SCPE Study

BACKGROUND

Postneonatal cerebral palsy (PNCP) is rare and requires large databases to be studied over time.

OBJECTIVES

To study the time trend of prevalence of PNCP overall and by cause, and to describe the clinical characteristics of children with PNCP according to cause and compared with children with pre/peri/neonatal CP (PPNCP).

METHODS

The Surveillance of Cerebral Palsy in Europe (SCPE) database was used. Primary events (the first known chronological event in the causal chain) were classified according to the SCPE classification (six main and 19 sub-categories). Prevalence trends for children born during 1976-2012 were modelled using multilevel generalised linear models. The clinical characteristics of PNCP and PPNCP cases born after 1998 were reported as proportions.

RESULTS

The prevalence rates of PNCP were 1.76 (95% confidence interval (CI) 1.37, 2.23) and 0.82 per 10,000 live births (95% CI 0.73, 0.92) in children born during 1976-1980 and 2006-2012, respectively. The models showed a 2% annual decline in overall prevalence (prevalence rate multiplied by 0.98 each year) and a 10% decline for infectious causes for every 5-year change. The prevalence rate in children born during 2006-2012 was 0.26 per 10,000 (95% CI 0.21, 0.32) for infectious causes, which remained the most frequent. No trend emerged for other causes. Unilateral spastic CP, associated impairments and severe gross motor dysfunction were more frequent in PNCP than in PPNCP, and PNCP showed predominantly grey matter injury (55.6%). Seventeen percent were born preterm. PNCP differed by cause, with cerebrovascular accidents presenting the least severe and hypoxic causes the most severe forms.

CONCLUSION

Our study confirms the decrease in the prevalence of PNCP in children born up to 2012, particularly for CP, due to infectious causes, which remain the most frequent. Children with PNCP had more severe presentation overall than those with PPNCP, with severity depending on the cause.

Major structural congenital anomalies and causal pathways in people with cerebral palsy

AIM

To determine the proportion of persons with cerebral palsy (CP) with major congenital anomalies, factors associated with the presence of anomalies, body systems involved, potential contribution to CP aetiology, and causal pathway subgroups implicated.

METHOD

This population-based, observational study involved a cohort of 2238 persons born in one Australian state between 1999 and 2017. Major congenital anomalies were classified as affecting cerebral, cardiac, or other body systems, with further categorization as single or multisystem. We determined the potential for anomalies to contribute to the development of CP across causal pathway subgroups that were broadly categorized as developmental or involving destructive brain insults.

RESULTS

Of persons with CP, 23% had major congenital anomalies and 17% of the cohort had anomalies that potentially contributed to the development of CP. Consistent with higher odds of parental consanguinity, maternal grand multiparity, and dysmorphic features in the group with anomalies, 82% of pathogenic anomalies, present in 14% of the cohort, were cerebral and involved developmental causal pathways. Only 3% (predominantly severe cardiac anomalies) were related to destructive brain insults.

INTERPRETATION

The study provides context for the impact on rates of CP of preventive measures or other changes in incidence or management of congenital anomalies.

Indications for tracheostomy placement in pediatric patients with cerebral palsy

BACKGROUND

Cerebral palsy (CP) is the most common neuromuscular disorder in children, and children with CP are at increased risk of respiratory distress potentially requiring tracheostomy placement. Previous studies have characterized indications for tracheostomy in neurologically compromised children, however no studies focus specifically on children with CP. The purpose of this study was to identify the indications for tracheostomy placement, sites of airway obstruction, and rate of decannulation in children with CP.

METHODS

We conducted a single-center retrospective chart review of all patients who presented with cerebral palsy and required tracheostomy at our center between 2005 and 2023. Patients were categorized according to primary indication for tracheostomy placement. The most common sites of airway obstruction in the cohort were recorded. The date of decannulation was recorded for those patients who had undergone decannulation.

RESULTS

933 patients with tracheostomies were identified, of whom 169 (18 %) had CP and 122 met inclusion criteria. The median age at tracheostomy placement was 1.69 (IQR 0.539-6.609) years. The most common indications for tracheostomy placement were: prolonged intubation or BiPAP dependence (81 %), airway obstruction/hypotonia (13 %), and aspiration/recurrent respiratory infection (6 %). At the time of tracheostomy placement: 38 % of patients had a single site of upper airway obstruction, while 27 % had multi-level obstruction. The most common sites of upper airway obstruction were the supraglottis (23.0 %), tongue base (12 %), and the tonsils/pharyngeal wall (8 %). 24 % of patients had tracheobronchomalacia, and 16 % had subglottic stenosis. Among all patients, 4 of 122 (3 %) were ultimately decannulated.

CONCLUSIONS

Patients in our cohort most often received tracheostomy after failure of less invasive ventilation therapies. Tracheostomy placement occurred at a young age. Patients presented with a variety of sites of airway obstruction. Decannulation rate in this cohort was low. Further work is needed to confirm indications for tracheostomy placement and decannulation rate in this population.

Genetic investigations in cerebral palsy

The original description of cerebral palsy (CP) contained case histories suggesting that perinatal environmental stressors resulted in brain injury and neurodevelopmental disability. While there are clear associations between environmental impact on brain development and CP, recent studies indicate an 11% to 40% incidence of monogenic conditions in patients given a diagnosis of CP. A genetic diagnosis supports the delivery of personalized medicine. In this review, we describe how the Wnt pathway exemplifies our understanding of pathophysiology related to a gene variant (CTNNB1) found in some children diagnosed with CP. We cover studies undertaken to establish the baseline prevalence of monogenic conditions in populations attending CP clinics. We list factors indicating increased likelihood of a genomic diagnosis; and we highlight the need for a comprehensive, accurate, genotype-phenotype reference data set to aid variant interpretation in CP cohorts. We also consider the wider societal implications of genomic management of CP including significance of the diagnostic label, benefits and pitfalls of a genetic diagnosis, logistics, and cost.

Hip displacement in children with post-neonatal cerebral palsy and acquired brain injury: a systematic review

AIM

To systematically review the prevalence, risk factors and timing of onset of hip displacement in children with a post-neonatal (PNN) brain injury with regards to hip surveillance recommendations.

METHOD

A search of PubMed, MEDLINE, Embase, CINAHL and Web of Science was conducted on 22nd February 2022. Studies were included if they reported presence of, and risk factors for, hip displacement in children with PNN brain injury. Data was extracted on patient characteristics, and analyzed in terms of risk factors of interest and timing of development of hip displacement.

RESULTS

Six studies met the inclusion criteria (n = 408 participants). All were cohort studies: five retrospective and one prospective. Rates of hip displacement ranged from 1% to 100%, and were higher in children with diffuse brain injury at an early age, who were non-ambulant and had spastic quadriplegia. Hip displacement and hip dislocation were first identified at one and three months respectively following PNN brain injury.

INTERPRETATION

Evidence on hip displacement in children with PNN brain injury is sparse and low quality. Children who remain non-ambulant after diffuse PNN brain injury before five years of age appear most at risk of developing progressive hip displacement and earlier hip surveillance is recommended.

Cerebral palsy registers around the world: A survey

AIM

To provide a description of cerebral palsy (CP) registers globally, identify which aim to report on CP epidemiology, and report similarities and differences across topics of importance for the sustainability and collaboration between registers.

METHOD

Representatives of all known CP registers globally (n = 57) were invited to participate. The online survey included 68 questions across aims, methodologies, output/impact, and stakeholder involvement. Responses were analysed using descriptive statistics.

RESULTS

Forty-five registers participated, including three register networks. Twenty were newly established or under development, including 12 in low- and middle-income countries (LMICs). An epidemiological aim was reported by 91% of registers. Funding is received by 85% of registers, most often from not-for-profit organizations. CP definitions are comparable across registers. While the minimum data set of a register network is used by most registers, only 25% of identified items are collected by all three register networks. Ninety per cent of registers measure research activities/output, and 64% measure research impact. People with lived experience are involved in 62% of registers.

INTERPRETATION

There has been a recent surge in CP registers globally, particularly in LMICs, which will improve understanding of CP epidemiology. Ongoing efforts to address identified methodological differences are essential to validate comparison of results and support register collaboration.

WHAT THIS PAPER ADDS

Cerebral palsy (CP) registers represent an increasing number of regions, including low- and middle-income, worldwide. Most registers collect the minimum data set of a CP register network. Research activities/output and impact are measured by most registers. The majority of registers involve people with lived experience in operation or research.

Classification of events contributing to postneonatal cerebral palsy: Development, reliability, and recommendations for use

AIM

This paper introduces the Surveillance of Cerebral Palsy in Europe (SCPE) classification of events contributing to postneonatally acquired cerebral palsy, presents its interrater reliability, and describes the cases identified in the SCPE database.

METHOD

The development of the classification, based on literature review and expert discussions, resulted in six main categories and 19 subcategories. The first chronological event designated as the primary event was mainly reported. Interrater reliability was assessed through online exercise providing 24 clinical vignettes representing single/complex pathways. Percent agreement and Gwet's AC1 index of reliability were estimated. Primary events were described using data of 221 children born between 2008 and 2012.

RESULTS

Thirty-nine professionals (21 registries) participated in the reliability exercise. Substantial overall agreement was reached (0.75), with some contrast between complex (0.48, moderate agreement) and single events involved (0.89, almost perfect). The distribution of primary events showed that 32.1% were infections (category A), 23.1% head injuries (B), 15.4% related to surgery or medical interventions (C), 13.1% cerebrovascular accidents (D), 9.1% hypoxic brain damaging events of other origins (E), and 7.2% miscellaneous (F).

INTERPRETATION

This classification allows all the events involved to be recorded while consistently reporting the primary event, and may be used in different settings.

WHAT THIS PAPER ADDS

A standardized classification enables the description of the events contributing to postneonatal cerebral palsy (CP). The first chronological event in complex pathway leading to CP is coded. Category choice and coding of the primary event identify preventable situations. The detailed 2-level classification is easy to use in various settings. Substantial overall interrater reliability shows that main categories can be consistently differentiated.

Severe Congenital Heart Defects and Cerebral Palsy

OBJECTIVE

To report the prevalence of cerebral palsy (CP) in children with severe congenital heart defects (sCHD) and the outcome/severity of the CP.

METHODS

Population-based, data linkage study between CP and congenital anomaly registers in Europe and Australia. The EUROCAT definition of severe CHD (sCHD) was used. Linked data from 4 regions in Europe and 2 in Australia were included. All children born in the regions from 1991 through 2009 diagnosed with CP and/or sCHD were included. Linkage was completed locally. Deidentified linked data were pooled for analyses.

RESULTS

The study sample included 4989 children with CP and 3684 children with sCHD. The total number of livebirths in the population was 1 734 612. The prevalence of CP was 2.9 per 1000 births (95% CI, 2.8-3.0) and the prevalence of sCHD was 2.1 per 1000 births (95% CI, 2.1-2.2). Of children with sCHD, 1.5% (n = 57) had a diagnosis of CP, of which 35 (61%) children had prenatally or perinatally acquired CP (resulting from a brain injury at ≤28 days of life) and 22 (39%) children had a postneonatal cause (a brain injury between 28 days and 2 years). Children with CP and sCHD more often had unilateral spastic CP and more intellectual impairments than children with CP without congenital anomalies.

CONCLUSIONS

In high-income countries, the proportion of children with CP is much higher in children with sCHD than in the background population. The severity of disease in children with CP and sCHD is milder compared with children with CP without congenital anomalies.

Temporal trends, clinical characteristics, and sociodemographic profile of post-neonatally acquired cerebral palsy in Australia, 1973-2012: A population-based observational study

AIM

To describe post-neonatally acquired (PNN) cerebral palsy (CP) in terms of temporal trends in prevalence, clinical and sociodemographic profiles, known causes and associations between causes, and sociodemographic variables.

METHOD

Numerator data, a count of children with PNN-CP confirmed at 5 years of age (n = 523), was drawn from two Australian state CP registers (birth years 1973-2012). Poisson regression was used to investigate temporal trends in the prevalence of PNN-CP by 5-year intervals, calculated per 10 000 live births. Using data from all state and territory Australian CP registers (n = 469), distributions of clinical characteristics, PNN-CP causes, and sociodemographic factors were tabulated (birth years 1995-2012). χ2 and logistic regression analyses were used to assess associations between sociodemographic profile, Australian reference data, and known causes.

RESULTS

A significant temporal decline in PNN-CP in Victoria (p = 0.047) and Western Australia (p = 0.033) was observed. The most common proximal causes of PNN-CP were cerebrovascular accidents (34%, n = 158), infection (25%, n = 117), and non-accidental injuries (12%, n = 58). Children born to teenage mothers, Aboriginal and/or Torres Strait Islander mothers, or children born in remote areas were over-represented in this cohort compared with reference data (all p ≤ 0.001). Infectious causes were strongly associated with teenage motherhood (odds ratio 3.0 [95% confidence interval 1.1-8.2], p = 0.028) and remote living (odds ratio 4.5 [95% confidence interval 2.0-10.2], p < 0.001).

INTERPRETATION

Although prevalence of PNN-CP has declined, the over-representation of priority populations, and the relative severity of a condition that is largely preventable, suggest the need for more specific primary preventive measures and support.

WHAT THIS PAPER ADDS

Prevalence of post-neonatally acquired (PNN) cerebral palsy (CP) in Australia significantly declined between 1973 and 2012. Cerebrovascular accidents are the most common proximal cause of PNN-CP. Children born in remote areas are at greater risk of PNN-CP.

High occurrence of perinatal risk factors and more severe impairments in children with postneonatal cerebral palsy in Norway

AIM

To describe causal events, perinatal risk factors and clinical characteristics in children with postneonatal cerebral palsy (PNCP).

METHODS

Population-based registry study of Norwegian children born 1999-2013. Prevalence, causal events and clinical characteristics of PNCP were described. The occurrence of perinatal risk factors for CP was compared with the general population.

RESULTS

Among 1710 children with CP, 67 had PNCP (3.9%; 0.75 per 10,000 livebirths [95%CI: 0.59-0.96]). The prevalence of PNCP decreased during the study period. Leading causal events were cerebrovascular events (32.8%), head injuries/other accidents (22.4%), infections (19.4%) and hypoxic events (14.9%). Spastic hemiplegic (53.7%) or spastic quadriplegic/dyskinetic CP (31.3%) was more common in children with PNCP than non-PNCP (42.3% and 20.1%, respectively; p < 0.001). Children with PNCP had more severe motor and associated impairments. Perinatal risk factors for CP were more common in children with PNCP than in the general population.

CONCLUSION

The prevalence of PNCP among Norwegian children was low and decreasing. The main causes were cerebrovascular events and head injuries/other accidents. Although spastic hemiplegic CP was the dominating subtype, children with PNCP had more severe motor and associated impairments than children with non-PNCP, as well as a higher occurrence of perinatal risk factors than in the general population.