Cerebral Palsy: New findings inform better preventive care

Introduction
 
Cerebral palsy (CP) is a group of non-progressive neurological disorders that affect movement, muscle tone, and posture. It is caused by damage or abnormalities in the developing brain, typically occurring before, during, or shortly after birth. The incidence of CP in the general population is approximately 2 to 3 cases per 1,000 live births [1]. Symptoms can vary greatly depending on the type and severity of the condition, and include impaired muscle coordination, stiff or tight muscles, exaggerated reflexes, involuntary movements, difficulty with balance and posture, and problems with speech, swallowing, and vision [2]. The etiology of CP is multifactorial and can be attributed to various causes, including genetic factors, maternal infections during pregnancy, premature birth, birth injuries, and neonatal complications such as lack of oxygen or severe jaundice [3].
 
There are four main types of CP, classified based on the area of the brain affected and the resulting movement disorder. The morbidity associated with each type of CP can vary significantly. Spastic Cerebral Palsy is the most common type, characterized by stiff and tight muscles, often affecting the legs more than the arms. It is caused by damage to the motor cortex, the area of the brain responsible for voluntary movement. Dyskinetic Cerebral Palsy involves uncontrolled, involuntary movements, such as twisting or writhing motions. It is caused by damage to the basal ganglia, which control involuntary movements. Ataxic Cerebral Palsy is due to damage to the cerebellum, which is responsible for coordinating movement and balance. Individuals with this type have poor balance and coordination. Individuals with Mixed Cerebral Palsy may exhibit symptoms of more than one type of cerebral palsy, indicating that multiple areas of the brain have been affected [4,5].
 
The standard of care for patients with CP involves a multidisciplinary approach, including physical therapy, occupational therapy, speech therapy, and medical interventions as needed. Physical therapy aims to improve muscle strength, flexibility, and mobility, while occupational therapy focuses on developing skills for daily living activities. Speech therapy can address communication and swallowing difficulties. Medications, orthotics, and surgical interventions may be recommended in some cases to manage spasticity, contractures, or other complications. Assistive devices, such as walkers, wheelchairs, or communication aids, may also be necessary for some individuals [6].
 
While CP is a lifelong condition, many individuals with milder forms have a normal life expectancy, especially with proper medical care and supportive services [7]. However, individuals with more severe forms of CP or associated conditions, such as intellectual disabilities or respiratory problems, may have a reduced life expectancy by as much as 40% compared to the general population. On average, adults with CP die 24 years earlier than adults without CP [8]. Morbidity related to neurological impairments is certainly an exacerbating factor. Two aspects of current research efforts aimed at understanding its effects leading to earlier mortality are discussed below.
 
References
[1] CDC- Data and Statistics for Cerebral Palsy
[2] NINDS: Cerebral Palsy-Symptoms
[3] CDC- Risk factors for Cerebral Palsy
[4] NINDS: Cerebral Palsy Types and corresponding brain damages
[5] Cerebral Palsy Guide: Co-existing Conditions
[6] American Academy of Pediatrics/Patient Care/Cerebral Palsy
[7] Cerebral Palsy Guide: Life Expectancy
[8] Survival and mortality in cerebral palsy: observations to the sixth decade from a data linkage study of a total population register and National Death Index. Blair E, Langdon K, McIntyre S, Lawrence D and Watson L. BMC Neurology (2019) 19: 111. https://doi.org/10.1186/s12883-019-1343-1


Causes of death among adults with and without cerebral palsy
 
In a recent study of 13,332,871 individuals who died in the US from 2013 to 2017, the causes of death were reported for individuals with CP (n=13,897) compared to those without (N=13,318,974) [1]. The leading causes of death were grouped into 11 categories including 1) heart disease, 2) pneumonitis, 3) influenza & pneumonia, 4) respiratory failure, 5) malignant neoplasms, 6) choking, 7) septicemia, 8) genitourinary diseases, 9) chronic lower respiratory diseases, 10) cerebrovascular diseases, and 11) unknown/unspecified.
 
It was evident from the results that adults with CP had a much higher likelihood than individuals without, of dying from respiratory causes including:

• Pneumonitis (adjusted odds ratio [aOR] 31.14)
• Choking (aOR 20.66)
• Respiratory failure (aOR 17.24)
• Influenza & pneumonia (aOR 8.78)

 
And also in 3 other categories:

• Unknown/unspecified causes (aOR 19.0)
• Septicemia (aOR 1.92)
• Genitourinary diseases (1.67)

 
They had a lower likelihood than individuals without, of dying from:

• Cerebrovascular diseases (aOR 0.66)
• Heart disease (aOR 0.61)
• Chronic lower respiratory diseases (aOR 0.50)
• Malignant neoplasms (aOR 0.12)

 
Interestingly, although CP individuals were less likely to die from heart disease compared to individuals without, it is the leading cause of death within the group followed closely by pneumonitis and influenza and pneumonia. Demographic differences were also noted. Among CP individuals females were more likely than males to die from respiratory failure whereas Non-Hispanic Black were more likely than Non-Hispanic White to die from heart and cerebrovascular diseases.
 
Recommendations: Overall, the implications of the study were two-fold. Despite heart disease being the leading cause of death for both groups, adults with CP faced a higher likelihood of death from preventable respiratory causes. Public health efforts should address respiratory health in this population. Non-Hispanic Black adults had specific disparities in cardiovascular health. Multifaceted approaches are needed to improve circulatory health among people with CP.
 
References
[1] Cause of death trends among adults with and without cerebral palsy in the United States, 2013−2017. Stevens J D, Turk M A and Landes S D. Annals of Physical and Rehabilitation Medicine 65 (2022) 101553. ). https://doi.org/10.1016/j.rehab.2021.101553

The study by Stevens, Turk and Landes was corroborated by a more recent meta-analysis of multiple smaller studies [2]. It also extends a 2019 study of a CP population from Western Australia [3].
 
[2] Risk Factors for Mortality in Patients With Cerebral Palsy: A Systematic Review and Meta-Analysis. Aldharman SS et al. Alhamad F S, Alharbi R M, et al. . Cureus 15(5): e39327. DOI 10.7759/cureus.39327
[3] Survival and mortality in cerebral palsy: observations to the sixth decade from a data linkage study of a total population register and National Death Index. Blair E, Langdon K, McIntyre S, Lawrence D and Watson L. BMC Neurology (2019) 19: 111. https://doi.org/10.1186/s12883-019-1343-1
 

Early onset of chronic diseases in young individuals with cerebral palsy
 
A 2022 study by Daniel G. Whitney [1] focused on a different aspect of cerebral palsy. It examined the risk of “adult-onset” chronic diseases in young children with CP utilizing a population of 5,559 aged 1-13 years from a general group of 2,324,035 children eligible for analysis. The adult-onset chronic diseases were grouped into 13 categories including 1) cerebrovascular disease, 2) cardiac conduction disorders and dysrhythmias, 3) heart failure, 4) chronic obstructive pulmonary disease, 5) type 2 diabetes, 6) chronic kidney disease stage I-IV or end stage renal disease, 7) other chronic kidney diseases, 8) hypothyroidism, 9) liver disease, 10) metastatic cancer, 11) any malignancy except malignant neoplasm of the skin, 12) depression and 13) osteoarthritis.
 
Findings: Children with CP had a higher 5-year risk of all chronic diseases compared to those without CP. The relative risk (RR) ranged from 1.19 to 64.26 (all P < 0.05) across different chronic diseases. The increased risk was observed in all age groups (baseline age groups: <1–2, 3–5, 6–8, 9–11, 12–13 years old).
 
Top tier: cerebrovascular disease (RR 64.26), heart failure (RR 15.17), chronic kidney disease stage I-IV or end stage renal disease (RR 14.97) and metastatic cancer (RR 9.81)
 
Second tier: liver disease (RR 7.97), any malignancy except malignant neoplasm of the skin (RR 6.51), other chronic kidney diseases (RR 6.49) and cardiac conduction disorders and dysrhythmias (RR 6.47)
 
Third tier: hypothyroidism (RR 5.02), osteoarthritis (RR 5.00), type 2 diabetes (RR 2.64), chronic obstructive pulmonary disease (RR 1.68) and depression (RR 1.19)
 
Among children with cerebral palsy, certain patient-level factors could slightly influence the risk of chronic diseases. For examples, comparing chronic disease risk in male versus female, most notably male had a slightly higher risk of chronic obstructive pulmonary disease (20%) but lower risk of chronic kidney disease (31%) and liver disease (35%). Co-occurrence of intellectual disabilities and/or epilepsy increases risk across all chronic diseases except depression. The use of wheelchairs also increased the risk of many chronic diseases to varying levels.
 
Clinical Implications: The study provides novel epidemiologic evidence of 5-year risk of “adult-onset” chronic diseases during important developmental stages in children with cerebral palsy. Identifying at-risk children based on patient-level factors can enhance clinical detection. These findings may inform the timing of prevention strategies and help identify those more susceptible to chronic diseases.
 
Reference
[1] 5-year risk of “adult-onset” chronic diseases during childhood and adolescent transitioning for individuals with cerebral palsy. Whitney D J. Preventive Medicine Reports 29 (2022) 101933. https://doi.org/10.1016/j.pmedr.2022.101933

Online resources
 
General Information and Education

• Cerebral Palsy Guide
• Cerebral Palsy Foundation (CPF)
• United Cerebral Palsy (UCP)
• Centers for Disease Control and Prevention (CDC) - Cerebral Palsy

 
Medical and Therapeutic Resources

• American Academy for Cerebral Palsy and Developmental Medicine (AACPDM
• National Institute of Neurological Disorders and Stroke (NINDS) - Cerebral Palsy Information Page

 
Support and Advocacy

• Cerebral Palsy Alliance Research Foundation (CPARF)
• Family Voices

 
Community and Networking

• MyChild at CerebralPalsy.org
• March of Dimes - Cerebral Palsy

 
Financial and Legal Assistance

• Social Security Administration (SSA) - Disability Benefits for Cerebral Palsy
• Patient Advocate Foundation
• Cerebral Palsy Toolkit (provided by Levin & Perconti, a private law firm)

 
These resources offer a wealth of information and support for individuals with cerebral palsy and their caregivers, helping them navigate the challenges associated with the condition and improve their quality of life.