Intellectual Disability And Adaptive Functioning

Overview

Intellectual Disability (ID) is a significant limitation in both intellectual ability and adaptive functioning, but many studies of participants with intellectual disability only include a measure of overall intellectual functioning when describing their samples.¹ Meanwhile, adaptive behaviours are a priority for the overall functioning of the individual in daily life activities.²

Causes of intellectual disability (ID)

There are many different causes of intellectual disability, the following factors are thought to increase the risk of its development:

• The most prevalent factor in Intellectual Disability is genetic factors. Different genetic causes may lead to ID such as Down syndrome (trisomy 21) or Fragile X syndrome.
• Environmental factors such as exposure to toxic substances (e.g., prenatal alcohol exposure, prenatal or postnatal lead exposure), nutritional deficiencies (e.g., prenatal iodine deficiency), brain radiation, childhood brain infections, traumatic brain injury, and maternal infections (e.g., rubella, cytomegalovirus) can lead to Intellectual Disability. Additionally, prenatal and postnatal complications e.g., complications of prematurity such as hypoxemia and periventricular haemorrhage may cause brain injury resulting in ID.
• Intellectual Disability may develop following an illness such as meningitis, whooping cough or measles; may result from head trauma during childhood; or may result from exposure to toxins such as lead or mercury.³

Diagnostic criteria of intellectual disability (ID)

According to the Diagnostic and Statistical Manual of Mental Disorders Fifth Edition (DSM-5), the diagnosis of Intellectual disability requires deficits in intellectual function, deficits in adaptive functioning, and onset before the age of 18.⁴

• Deficits in intellectual function, such as reasoning, problem-solving, planning, abstract thinking, judgment, academics, and learning from experience, are confirmed by clinical assessment and individualized, standardized intelligence testing.
• Deficits in adaptive functioning that fail to meet developmental and sociocultural standards for personal independence and social responsibility. Without ongoing support, the adaptive deficits limit functioning in one or more daily activities, such as communication, social participation, and independent living, across multiple environments, such as home, school, work, and community.
• The onset of intellectual and adaptive deficits during the developmental period. ^3,4

What is intellectual functioning in ID?

Intellectual functioning is generally called intelligence and includes a wide range of mental activities such as the ability of logical reasoning and practical intelligence (problem-solving), the ability to learn, and verbal skills. It is displayed through numerous abilities, behaviours, thoughts, and emotions. Essentially, intellectual functioning is the overall capability that enables an individual to comprehend and interact with reality.⁵

Intellectual functioning is typically assessed using the intelligence quotient (IQ), which is a score derived from standardized tests designed to measure human intelligence. The average IQ score is set at 100, with a standard deviation of 15. A score of 70 or below, which is two standard deviations below the average, signifies intellectual limitations.⁵

What is adaptive behaviour in ID?

Disabilities in adaptive functioning manifest as a lack of competence in social, conceptual, and practical skills that people typically use in daily life.⁵

• Conceptual: Includes abilities such as language, reading, writing, math, reasoning, knowledge, and memory.
• Social: Encompasses empathy, social judgment, communication skills, the ability to follow rules, and the ability to form and maintain friendships.
• Practical: Involves independence in areas such as personal care, job responsibilities, managing money, recreation, and organizing tasks related to school and work.⁵

Adaptive functioning is evaluated using standardized measures and interviews with individuals such as family members, teachers, and caregivers. These skills are acquired throughout development and are used to address common problems and tasks, both simple and complex, as well as to meet societal and community expectations. As individuals age, their behavioural responses become increasingly complex. Several validated tools are available to assess limitations in adaptive behaviour.

Management for intellectual disability (ID)

Intellectual disability is a life-long condition. However, early and ongoing intervention may improve functioning and the quality of everyday life.^3,5

• Educational support is an extremely important intervention for children with Intellectual Disabilities. Medical professionals must approach the school promptly to arrange special education modifications. In addition to academic modifications, schools should offer transition planning from childhood to adulthood that promotes self-sufficiency, as well as teaching behavior skills, vocational skills, communication skills, functional living skills, and social skills that are tailored to the individual's needs. Students with an ID should be placed in the least restrictive environment which means as much as tolerated in general classes. ^5,6
• Behavioural therapy is aimed at encouraging positive behaviour and discouraging undesirable behaviour. The effective methods of behavioural therapy are providing positive reinforcement and benign punishments, avoiding triggers of negative demeanour, shunning misconduct, and redirecting to prevent or curtail any troublesome behaviour. Cognitive therapy is also a form of behavioural therapy, that focuses on the connection between behaviour, emotions, and cognitions, and seeks to correct individuals' negative behaviours by identifying and modifying negative thoughts.^5,7
• Vocational training is important for young adults or teenagers to gain the necessary skills to enter the workforce. Through activities supervised by a social worker, occupational therapist, teacher, counsellor, and psychologist, patients learn how to keep themselves clean, wear appropriate clothes, and carry out their responsibilities.^5,8
• Family education is a crucial service offered by healthcare providers to the relatives of individuals with intellectual disabilities. Initially, this involves helping family members understand the nature of intellectual disabilities, including its definition, management strategies, and prognosis. Subsequently, healthcare professionals can assist families with placement decisions, recommend suitable services and equipment, and offer caregiver training. Additionally, physicians need to recognize that family members often experience considerable stress and must support them through psychosocial challenges like the need for respect, feelings of helplessness, depression, and anxiety. Providing robust support to the family ultimately fosters a nurturing home environment for the patient.⁵
• Psychopharmacologic therapies are not the primary component of intellectual disability treatment, but they can significantly reduce behavioural abnormalities associated with the disorders. Patients can suffer from harmful behaviours, such as involuntary movements, repetitive self-stimulatory behaviour, obsessive-compulsive symptoms, and self-injurious behaviours. These symptoms can be reduced with antipsychotic medications, although there was no observation of improvement in adaptive behaviour. To treat repetitive self-stimulatory behaviour and obsessive-compulsive symptoms can be used SSRIs.⁵

FAQs

How can I prevent intellectual disability during childhood?

Preventing intellectual disability in children involves understanding its causes and taking proactive measures to ensure their safety and health as follows:

• Childhood immunizations by vaccinating children against at least six diseases that can cause brain damage, such as measles, mumps, whooping cough (pertussis), Hib disease, chickenpox (varicella), and pneumococcal disease.
• Injury prevention by avoiding brain injuries by using bicycle helmets, safety seats, and seat belts in cars; preventing near-drowning incidents; avoiding falls; and protecting babies from severe shaking.
• Newborn screening by identifying treatable genetic conditions early through newborn screening.
• Protecting children from poisonous household products
• Reducing Reye’s Syndrome by avoiding medicines containing salicylate (aspirin) and using acetaminophen instead to reduce the risk of brain damage.

How can I help my kid with intellectual disability?

As a parent of a child with a disability, it is crucial to seek help and educate yourself about your child's condition. Connecting with other parents in similar situations can provide valuable support and insights. Patience is essential, as your child's learning may progress at a slower pace. Encourage their independence and responsibility, and make sure you are informed about the educational services they are entitled to. Familiarize yourself with the laws designed to support your child's well-being and ensure they have access to opportunities in your community for social, recreational, and sports activities.

Why is prenatal care important in preventing ID?

The health of a baby is closely linked to the mother’s health before pregnancy. Ideally, women should undergo a comprehensive health evaluation six months before conceiving. This evaluation should include updating immunizations, reviewing the use of medications, assessing diet and vitamin supplementation (particularly folic acid), considering genetic counselling, and discontinuing the use of alcohol, cigarettes, or other tobacco forms, illegal drugs, and any legal drugs not approved by the doctor.

If a woman is suspected pregnant, then prenatal care should begin promptly. During pregnancy, she can protect the developing fetus by getting plenty of rest and sleep, eating nutritious meals, avoiding alcohol, cigarettes, and drugs, steering clear of people who are sick, wearing seat belts in a car, and refraining from lifting heavy objects.

Summary

Intellectual Disability (ID) is one of neurodevelopmental disorders marked by a significant limitation in both adaptive ability and intellectual functioning. The major risk factors of ID are genetic factors and environmental factors. Once a diagnosis of intellectual disability is made, help for individuals with intellectual disability is focused on looking at the individual’s strengths and needs, and the supports they need to independently function in their daily activities.

Services for people with intellectual disabilities and their families can provide support to allow full inclusion in the community. Many different types of treatments and services can help, such as educational support, behaviour therapy, vocational training, family education, and psychopharmacologic interventions.