Tracking and Research on Cerebral Palsy

CDC has been studying the number of people with cerebral palsy (CP) since the early 1980s. By studying the number of children diagnosed with CP over time, we can find out if the number is rising, dropping, or staying the same. We can compare the number of children with CP in different groups of people and in different areas of the country. This information can help us look for causes and risk factors of cerebral palsy, evaluate the effectiveness of prevention efforts, raise awareness of the signs and symptoms, and help families and communities plan for services. Determining whether these changes affect the rates of CP over time requires ongoing, systematic population-based tracking.

Determining How Many People Have Cerebral Palsy—Tracking

CDC conducts tracking or surveillance programs in different populations across the United States to count the number of children with CP. These programs provide important information about the characteristics of children with CP, serve as the basis for future research, can answer questions about the causes of CP, and inform strategies for prevention.

The following are activities that CDC conducts or funds in order to learn more about the number and characteristics of children with CP:

Metropolitan Atlanta Developmental Disabilities Surveillance Program

MADDSP was established in 1991 to identify children with four disabilities (CP, hearing loss, intellectual disability, and vision impairment). A fifth disability, autism, was added to the program in 1996. MADDSP conducts ongoing tracking for developmental disabilities among 8-year-old children living in the metropolitan Atlanta area. This program has contributed a wealth of information on the characteristics, risk factors, costs, and implications of developmental disabilities, including CP.

Learn more about MADDSP »

Autism and Developmental Disabilities Monitoring Network

In 2000, CDC established a network of collaborative programs called the Autism and Developmental Disabilities Monitoring (ADDM) Network. The surveillance methods developed by MADDSP serve as the model for the ADDM Network—including CP tracking efforts. Currently, there are four sites tracking CP in selected areas of Alabama, Georgia, Missouri, and Wisconsin as part of the ADDM CP Network. The surveillance areas at these four ADDM CP sites accounted for approximately 3.5 percent of the U.S. eight year-old population in 2006. The goals of the ADDM CP Network are:

• To obtain as complete a count as possible of the number of children with CP in each project area.
  
  
• To study whether CP is more common in some groups of children than among others and whether rates are changing over time.
  
  
• To improve the consistency of identification of people with CP.
  
  
• To provide information on the characteristics of children with CP, including functional abilities and co-existing conditions, such as epilepsy.
  
  

In 2006, an estimated 3.3 per 1,000 8-year-old children across the ADDM CP Network, or about 1 in 303, had CP. [Read article]

Metropolitan Atlanta Developmental Disabilities Study (MADDS)

CDC studied how many children in metropolitan Atlanta had CP in the mid-1980s. This project was done as part of the Metropolitan Atlanta Developmental Disabilities Study (MADDS), which studied how common certain disabilities were in 10-year-old children. This study served as the basis for the creation of Metropolitan Atlanta Developmental Disabilities Surveillance Program (MADDSP).

One of the key findings of this study was that 16% of children acquired CP more than 28 days after birth. The acquired CP cases were due to: [Read article]

• Infections, such as meningitis or encephalitis
  
  
• Head trauma, for example, from a motor vehicle accident or fall
  
  
• Cerebrovascular accidents, that is, bleeding or a blood clot in the brain
  
  
• Anoxia or lack of oxygen to the brain
  
  
• Low blood sugar
  
  

Findings from this program were published in the following article:

A multiple-source method for monitoring developmental disabilities in children

Learn more about MADDS »

National Surveys

CDC conducts the National Health Interview Survey (NHIS ) that provides data on health conditions in U.S. children and adults. The following recent articles published findings about trends in developmental disabilities and estimates of health-related limitations, needs, and service use among US children with CP:

Trends in the Prevalence of Developmental Disabilities in US Children, 1997-2008.

Health Care Use and Health and Functional Impact of Developmental Disabilities among US Children, 1997-2005.

Learn more about NHIS »

Understanding Risk Factors—Research

CDC supports public health research, including studying potential causes of CP and other developmental disabilities. Both public health tracking and research efforts provide information necessary to direct prevention efforts. Here are some of the research programs that CDC has been or is involved in:

The Metropolitan Atlanta Developmental Disabilities (MADDS) Follow-up Study of Young Adults

In the mid-1980s, CDC conducted the Metropolitan Atlanta Developmental Disabilities Study (MADDS), a study of developmental disabilities (including CP) in 10-year-old children living in metropolitan Atlanta. The Follow-Up Study of Children with Developmental Disabilities contacted many of the original study participants years later, when they were young adults. They were asked questions about various subjects, such as their health, living arrangements, socialization, employment, and quality of life to assess their current functioning and transition into adulthood.

Findings from this study were published in the following articles:

Transition Issues Among Young Adults with Developmental Disabilities

Healthy Lifestyle and Behaviors Among Young Adults with Developmental Disabilities

Functioning and Young Adults with Developmental Disabilities

Leisure Activities and Young Adults with Developmental Disabilities

The CDC-Denmark Program (Project Completed)

Through the CDC-Denmark program, CDC supported studies of CP using the Danish National Cerebral Palsy Register to examine factors that might make it more likely a child will develop CP. Factors that were examined include multiple births, preterm birth, assisted reproductive techniques, and asphyxia or lack of oxygen before or during birth.

Findings from this program were published in the following articles:

CP in Children Born After Assisted Conception

CP Among Children Born After in Vitro Fertilization

CP and Asphyxia

Infant Development Study (IDS)

In the early 1990s, CDC scientists looked at very low birth weight infants born in Georgia from 1986 to 1988, to examine the effects of treatment with prenatal magnesium sulfate (given either for pre-eclampsia or preterm labor) on the risk for CP in low birth weight children. The results showed that fewer children whose mothers were given magnesium sulfate were later diagnosed with cerebral palsy, compared to children whose mothers were not given the treatment.

Numerous large clinical studies have subsequently evaluated the protective effects of magnesium sulfate.⁽¹⁾ The Committee on Obstetric Practice and the Society for Maternal-Fetal Medicine state that the available evidence suggests that magnesium sulfate given before anticipated early preterm birth reduces the risk of cerebral palsy in surviving infants.⁽²⁾

References

1. Doyle LW, Crowther CA, Middleton P, Marret S, Rouse D. Magnesium sulphate for women at risk of preterm birth for neuroprotection of the fetus. Cochrane Database of Systematic Reviews 2009, Issue 1. Art. No.: CD004661. DOI: 10.1002/14651858.CD004661.pub3.

2. Magnesium sulfate before anticipated preterm birth for neuroprotection. Committee Opinion No. 455. American College of Obstetricians and Gynecologists. Obstet Gynecol 2010;115:669–71.