Intellectual Disability

Definition

According to World Health Organization Intellectual disability (ID) is characterized by deficient intellectual ability as evident through the worsening of conceptual, social and practical functioning at each stage of development in the areas of cognition, language, motor and socialization.

Causal factors

Causal factors can be classified as follows: genetic, acquired (congenital and developmental), environmental and sociocultural.

Among Genetic factors, the highest prevalence is of children with Down syndrome. Children with Down Syndrome have intellectual disability
Hereditary factors include conditions (such as phenylketonuria) which are transferred from parents to child. These conditions are also linked with intellectual disability and can be easily diagnosed during neonatal metabolic screening
Congenital factors include Metabolic factors such as deficiency of thyroid hormones at the time of birth, Toxic factors such as accumulation of toxic substances in baby due to lead poisoning or exposure to drug/substances/alcohol during prenatal period, and Infectious factors as children catching infections at the early age are also prone to brain damage.
Developmental causal factors include pregnancy complications exist, such as abrupt hypertension, swelling of hands, face and feet, diabetes, and intrauterine malnutrition etc. moreover, in perinatal period, delayed oxygen, suffocation, delayed cry and mishandling of baby during or after child birth are also the leading causes of intellectual disability. Postnatal period is also very important. Complications encephalopathies, accidents leading to brain damage or infections such as meningitis are also the major causal factors of intellectual disability.
Environmental and sociocultural factors are also well-researched areas by the epidemiologists. According to the, poverty and intellectual disability are highly linked. Poverty restricts the exposure environmental, psychological and social factors that may help in effective management of the disability. Moreover, families with members with ID already have to manage their finances which further affect their economic conditions. Unavailability of specialized maternity health care professionals and equipment, child care guidance, and appropriate level of stimulation to children with ID are leading factors leading to worsening of intellectual disability.

Diagnosis and Classification

Firstly, the diagnosis of intellectual disability is made after rigorous testing of culturally based intellectual assessment tests. Moreover, adaptive functioning is also assessed to know the functional age of the child. Based on the adaptive functioning, where child’s functioning in the areas of socialization, motor, language, cognitive and self-help skills is compared with the functioning of children with same age, child is categorized as mild, moderate, severe or profound.

The clinical history regarding prenatal, perinatal and postnatal period, IQ assessment, genetic conditions and congenital abnormalities is very important in order to finalize the diagnosis. Furthermore, the physical exam focusing on secondary abnormalities, congenital malformations and neurological assessment should also be conducted to evaluate the differential diagnosis.

Assessment of comorbid neurodevelopmental disorders specified by the mental health professionals should also be conducted. Moreover, Individuals with ID are more vulnerable for developing psychiatric issues these individuals are two or three times more diagnosed with mood disorders, anxiety disorders and behavioral problems than children without ID.

Treatment

Since ID is not curable, the treatment objectives must focus on the management of the condition.

At first, early intervention is fundamental children have their highest potential during to the first five years of life and benefitting from this time period to teach language and cognitive skills is very important. During the same period, parents are also guided and trained which also adds to the healthy management of the condition.
Individualized Education Plan is developed where focus is on the individual skills and deficits. The goals focus on development of skills for achieving an independent life at an adult age.
Physiotherapy, occupational therapy and sensory integration therapy to children with comorbid motor problems and/or sensory issues is also provided. Speech therapists work on speech development in cases where there are delays in speech due to various reasons.
For children, prevocational program is included to provide them basic skills needed to work in vocational domain.
Behavioral problems among individuals with ID are very common. Behavior therapy is mostly applied to manage the behaviors through different procedures especially positive reinforcement.
Behavior therapy is also applied to teach the child the independent living skills in order to be self-sufficient which include basic academics, functional academics, community integration programs, domestic skills, provision of guidance regarding personal healthcare and sexuality.
For children, prevocational program is included to provide them basic skills needed to work in vocational domain.
Pharmacological treatment is used to treat comorbidities such as attention deficit and hyperactivity disorder, epilepsy etc.

Lastly, it is important to mention that the treatment for children with intellectual disability must be multidisciplinary and include medicine (family, pediatrics, neurology and psychiatry), psychology (educational and clinical), education (regular, and special), rehabilitation (physical, occupational and recreational), nursing, social work, etc.