Developmentally Delayed Mental Retardation

Overview, Causes, & Risk Factors

Mental retardation is defined by three things. First, the person must have had the condition since childhood, or age 18 years or younger. Second, the person has a score of 70 or less on intelligence tests, or IQ tests. Third, the person has limitations in at least two aspects of living skills, such as:

  • communication
  • education, including reading, writing, and basic math
  • motor function
  • personal care, such as bathing, dressing, eating, and toileting
  • social skills
  • thinking skills, such as decision making, problem solving, and self-direction
  • working
  • What is going on in the body?

    People with mental retardation have reduced intellectual function. Sometimes it is because the brain has not formed properly. Or the brain is damaged after the child is born.

    What are the causes and risks of the condition?

    Mental retardation can be caused by a many factors, both before and after the child is born. More than 500 genetic disorders can cause mental retardation. Three are listed here:

  • Down syndrome
  • fragile X syndrome
  • phenylketonuria, or PKU
  • The following pregnancy-related problems in the mother can also cause mental retardation in the baby:

  • alcohol, smoking, or drug use during pregnancy
  • environmental toxins, such as lead and mercury
  • infections, such as the toxoplasma infection, also called toxoplasmosis \ \other infections, such as hepatitis B, syphilis, and herpes zoster, the virus that causes chickenpox \ \ rubella, the virus that causes German measles\ \ cytomegalovirus, or CMV\ \ herpes simplex virus, the cause of genital herpes \ TORCH infections or sexually transmitted diseases
  • malnutrition
  • Birth-related stresses may cause brain injury and result in mental retardation. Premature birth and low birth weight are often associated with mental retardation. Birth trauma and lack of oxygen may cause brain damage.

    Childhood infections, toxins, and accidents can also cause mental retardation. These include the following:

  • chickenpox, measles, and whooping cough
  • environmental toxins, such as lead and mercury
  • head injury
  • meningitis and encephalitis
  • near drowning
  • physical injuries from seizures
  • Factors related to poverty and cultural deprivation may also lead to mental retardation:

  • environmental hazards
  • lack of access to or inappropriate medical care
  • lack of nurturing and appropriate stimulation
  • living conditions that make exposure to diseases more likely
  • poor nutrition in early childhood
  • Symptoms & Signs

    What are the signs and symptoms of the condition?

    The following are some of the signs of mental retardation:

  • delayed development of skills such as walking and self care
  • late development of speech and language
  • poor coordination of movements, such as using the fingers to handle small objects
  • poor school performance
  • social and emotional immaturity
  • Diagnosis & Tests

    How is the condition diagnosed?

    Diagnosis of mental retardation begins with a medical history and physical exam. The healthcare provider may order the following additional tests:

  • blood tests
  • chromosome analysis
  • cognitive testing
  • cranial CT scan or cranial MRI
  • Prevention & Expectations

    What can be done to prevent the condition?

    Mental retardation caused by genetic factors often cannot be prevented. Early screening for PKU can identify infants who are at risk. The baby’s diet can then be tailored to prevent mental retardation. Some couples may consider genetic counseling if there is a family history of genetic disorders.

    Mental retardation can sometimes be prevented by proper prenatal care.

  • Avoid alcohol, drugs, and smoking during pregnancy.
  • Exercise and eat a healthy diet during pregnancy.
  • Get regular prenatal checkups and care as needed.
  • Mental retardation from factors during childhood can be reduced with the following measures.

  • Follow recommended schedules for well baby visits and childhood shots.
  • Remove lead and other toxins from the environment.
  • Use car safety seats.
  • Follow sports safety guidelines to avoid head injuries.
  • Provide regular stimulating contact with other children and adults.
  • What are the long-term effects of the condition?

    Long-term effects vary, depending on the degree of retardation. They may include:

  • a need for lifelong sheltered living and work environments
  • a need for help with basic activities of daily living, such as dressing and toileting
  • significant, lifelong health problems
  • poor decision-making ability
  • a need for help with financial decisions and management
  • emotional and social immaturity
  • What are the risks to others?

    Mental retardation is not contagious. It poses no risk to others.

    Treatment & Monitoring

    What are the treatments for the condition?

    Treatments for mental retardation may include:

  • early identification of the condition
  • enrollment in special education programs
  • medication as needed, such as anticonvulsants for seizures
  • occupational therapy, speech therapy, and physical therapy
  • respite care as needed
  • What are the side effects of the treatments?

    Most treatments for mental retardation are free from side effects. Medications may have specific side effects.

    What happens after treatment for the condition?

    Many people with mental retardation live happy, productive lives. They share loving relationships with friends and family and can make significant contributions to society. A mentally retarded person can receive special education services until the age of 21. Vocational services are available in sheltered workshop settings. Families are urged to do long-term planning for the time when the parents are no longer able to care for the person.

    How is the condition monitored?

    A person with mental retardation will have regular visits with the healthcare provider. Any new or worsening symptoms should be reported to the provider.

    Article type: xmedgeneral