by Karen Schroeder Kassel, MS, RD, MEd
Intellectual disability is often poorly understood because its effects vary greatly among those who have it. Many people with intellectual disability are mildly affected and may not be identified until later during school years. Individuals with intellectual disability may also have physical or emotional problems.
People with intellectual disability who have a very low intelligence quotient (IQ) have serious limitations in their ability to function. However, with early intervention and appropriate support, they can also lead satisfying lives. The goal of treating intellectual disability is to help children stay in the family and participate in community life. In most states in the United States, they are guaranteed education and other services.
What Is an Intellectual Disability?
Intellectual disability begins in childhood and is characterized by limitations in both intelligence and adaptive skills. The following three criteria must be met for a diagnosis of intellectual disability:
What Are the Causes? TOP
Any condition that impairs development of the brain before birth, during birth, or during childhood can cause intellectual disability. The main causes can be categorized as follows:
Genetic abnormalities may be inherited from parents or may be caused by environmental factors. There are many genetic diseases are associated with intellectual disability. Examples include:
Problems During Pregnancy
Problems at Birth
Prematurity and low birth weight may sometimes lead to intellectual disability. These conditions may be associated with bleeding in or around the brain. However, other birth conditions or physical stress in the newborn stage may injure an infant's brain.
Problems After Birth
Other conditions that can damage a child's brain and possibly lead to intellectual disability include:
How Is an Intellectual Disability Diagnosed? TOP
The American Association on Intellectual and Developmental Disabilities (AAIDD) has a process for diagnosing and classifying a person with intellectual disability. This process involves assessing the person's IQ and adaptive skills. Adaptive skills fall into three categories:
What Are the Treatment Options?
The best assistance for people with intellectual disability begins with diagnosis and help early in life. Treatment includes:
With enough education and support, many people with intellectual disability can learn to take care of their basic needs and to live in the community.
Can Intellectual Disabilities Be Prevented? TOP
Newborn screening followed by proper treatment can prevent intellectual disability resulting from certain conditions. Examples include:
Vaccines can prevent certain infectious diseases that may lead to intellectual disability. Women who plan to become pregnant should be current on all recommended vaccinations, such as:
Other interventions that can reduce the risk of intellectual disability include:
Many parents also choose to have certain tests done during pregnancy, including ultrasound, amniocentesis, chorionic villus sampling, and blood tests. These tests cannot prevent intellectual disability, but they can give parents more time to prepare for a child with intellectual disability.
American Association on Intellectual and Developmental Disabilities
Centers for Disease Control and Prevention
Definition of intellectual disability. American Association on Intellectual and Developmental Disabilities website. Available at: http://www.aamr.org/content_100.cfm?navID=21. Accessed August 22, 2012.
Intellectual disability. The ARC website. Available at: http://www.thearc.org/page.aspx?pid=2543. Accessed August 22, 2012.
Children who are mentally retarded. The American Academy of Child and Adolescent Psychiatry website. Available at: http://www.aacap.o.... Published July 2004. Accessed August 22, 2012.
Diagnostic adaptive behavior scale. American Association on Intellectual and Developmental Disabilities website. Available at: http://www.aaidd.o... . Accessed August 22, 2012..
Intellectual disability. EBSCO Health Library website. Available at: http://www.ebscohost.com/healthLibrary/ . Updated June 2012. Accessed August 22, 2012.
Intellectual disability. Kronkosky Charitable Foundation website. Available at: http://www.kronkos... . Published May 2009. Accessed August 22, 2012.
Intellectual disability. National Dissemination Center for Children With Disabilities website. Available at: http://nichcy.org/disability/specific/intellectual . Updated January 2011. Accessed August 22, 2012.
Intellectual disability. Merck website. Available at: http://www.merckma... . Updated February 2009. Accessed August 22, 2012.
Last reviewed August 2012 by Brian Randall, MD
Last Updated: 8/23/2012