Intellectual Disabilities / Mental Retardation
The intellectual disability is the disorder with limited intellect, learning, and self adaptation. In present, the word Intellectual Disability is increasingly substituting Mental Retardation by many international organizations such as IASSID (International Association for the Scientific Study of Intellectual Disabilities), WHO (World Health Organization), WPA (World Psychiatry Association), and especially AAMR (The American Association on Mental Retardation) which composes of worldwide inter-profession and has been founded for 130 years has renamed the association to be The American Association of Intellectual and Developmental Disabilities (AAIDD) since January 1, 2007 in order for the disabilities to be better accepted by the community.
Definition of the intellectual disability or mental retardation
As per the criteria of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM- IV-TR) by American Psychiatric Association (APA) in 2000, the intellectual disability or mental retardation means;
1. Lower IQ than average
2. Having adaptive behavior disorder by 2 out of 10 aspects
3. The symptoms reveal before 18 years old
Adaptive behavior means behaving in daily life which is the ability of a person to live his/her life in the community. The adaptive behaviors compose of:
1. Communication
2. Self-care
3. Home living
4. Social and Interpersonal Skills
5. Use of Community Resources
6. Self- direction
7. Functional Academic Skills
8. Leisure
9. Work
10. Health and Safety
AAMR or AAIDD, up until now, have changed the intellectual disability discrimination and diagnosis criteria for 10 times. At the 9th amendment in 1992 they changed the intellectual discrimination in accordance with the intelligence quotient (IQ) from 4 severities, i.e. mild, moderate, severe, and profound to be 2 severities, i.e. little (IQ=50-70) and extensive (IQ < 50) and emphasize on assistance level on demand.
This severity classification is to design and seek for supportive service for individual. The disabilities with IQ > 50 is classified educable, benefit from education, and the lower-than 50 disabilities will be classified trainable, emphasizing on the living skills.
Prevalence
In general, 1%-3% of population has been found intellectual disability. In Thailand, the prevalence of intellectual disability is found by 0.4%-4.7%, depending the reports whose research methodology is different.
Causes of intellectual disability
1. Genetic factor: found by 5%, either genetic disorder or chromosome aberration. The most found is down syndrome.
2. Abnormal development of the baby during pregnancy: found by 30% which may caused by the chromosome alteration, German measles, aids, syphilis, or other diseases during pregnancy of mother. It may also be caused from the chemicals mother received during pregnancy such as liquor, cigarette, radiation, drug, placenta abnormality such as toxemia of pregnancy or the abnormal central nervous at birth.
3. Problems during the pregnancy period and during birth giving: found by 10% which includes lack of nutrient of the baby, premature birth, injury that causes the cerebral hypoxia, bleeding in skull, lack of thyroid hormones, infection at birth such as herpes simplex.
4. Prenatal problems: found by 5% such as cerebral infection, encephalitis, meningitis, serious brain injury, cerebral hypoxia caused by drowning, lack of thyroid hormones, received chemical affecting the brain such as lead, or malnutrition.
5. Surrounding factors: found by 15%-20% which includes poverty and broken family, unusual interaction between the child and one who brings up the child, or very severe mental disorder including unknown cause for 30%.
Classification of intellectual disability
The classification may be conducted as per severity, cause, or assistance to the people with intellectual disability.
Intellectual disability classification according to DSM IV and Prevalence
|
IQ |
Severity of intellectual Disability |
Found Percentageบ |
|
55-69 |
Mild |
85 |
|
40-54 |
Moderate |
10 |
|
25-39 |
Severe |
3-4 |
|
<25 |
Profound |
1-2 |
Intellectual disability classification according to the assistance the people with intellectual disability need
The classification belongs to the American of Mental Retardation (AAMR) where IQ is not emphasized but the 10 adaptive behaviors is considered. This method is also related to the severity of the intellectual disability.
- Intermittent assistance
- Limited assistance
- Extensive assistance
- Pervasive assistance
Clinical characteristic
Delay development is the significant of the intellectual disability. The more the severity of the intellectual disability the earlier the delay development revealed. The severity of the intellectual disability is classified into:
1. Very severe intellectual disability development delay is eminent from very young both the movement and sensation. The children may be trained to help themselves however dedicate effort is required. Most of them found the pathology of all-the-time caring or even for life even in an adult.
2. Severe intellectual disability: the abnormal development was found during the first year. Delay development prevails in every aspect especially linguistic development. The child can communicate with limitation or non-communication. Some children can begin to speak when entering school. They have the movement problems. In some children, one or more pathology might be found. They have limited self protection skill. They have limited self care. They, however, can do some simple works and need close caring for all aspects for their lifelong.
3. Moderate intellectual disability: usually diagnosed before entering school at the age of 2-3 years. It was found that there might be difference of the capability in different aspects, for example, the down syndrome is delayed in language use, the Williams syndrome have visuo-spatial processing skills disorder. Some may be prominent in language use. Some can be found with distinctive pathology. They can study to grades 2-3. They usually need special education and can learn to walk by him/herself in the familiar places. They can live their life well in the community including their work. They need moderate assistance for life. About 20% can live their life on their own.
4. Mild intellectual disability often diagnosed when the child is entering school because at this age the social and communication skill are sufficient developed. Most of the children can stay in school until grade 6 or higher. When they are adult they can work, marry, and take care the family. However, they may need assistance some times. The pathological cause is not usually found. Most of the case, it relates to social factors and poor economic status or no chance. This shows the environmental and cultural factors that affect the intellectual disability.
Abnormalities
The mental disorder is found in the intellectual disability people by 30%-70% which is higher than normal population by 2-5 times. These disorders will be frequently found in more severe of the intellectual disability; most of them are behavioral problem such as naughty, short concentration, which were found by 9%-18%; self hurt by 36%; urge themselves such as applaud, standing on tiptoe by 15%-50%; stubborn, delinquent, worry by 1%-25%; psychosis, emotional disorder, or autistic behavior by 4%-8%.
Side effects
Ones with intellectual disability might have the side effects as follow:
1. Multiple handicaps, i.e. the handicap of body, legs, arms, blind, deaf, which are often found with severe and very severe case of the intellectual disability.
2. Challenging behavior such as strong emotion, harm others; harm themselves; damage things; or even eat a lot; lazy; steal; these behavior is the obstacles of social living.
3. Autistic - like behavior: the child separate him/herself from group into his/her own world.
4. Epilepsy can be found in the people with intellectual disability by 30%. If the symptom cannot be controlled it may cause more severe to the intellectual disability.
Care for the intellectual disabilities
Although when the intellectual disability occurs the lost brain cannot be brought back, we can maintain or rehabilitate the rest of it to be fully functioning. Therefore, the intellectual disability cure emphasizes on the brain and physical rehabilitation rather than giving medicine. The sooner the diagnosis is performed and the rehabilitation that is immediately conducted the better the intellectual disability restrain will result. The goal of intellectual disability treatment is not to eliminate the disease but to help the people with the disease to life like other people as much as possible so that they do not have to heavily rely on the family and society in that they can work on their career.
Rehabilitation to be performed on the intellectual disabilities
1. Medical Rehabilitation
The medical rehabilitation is the treatment given to the diseases commonly occurring with the intellectual disability to correct the handicap and rehabilitate physical conditions such as epilepsy, Cretinism, PKU, cerebral palsy. In addition to the symptom treatment the therapy is also required.
Early Intervention
Development enhancement is the skill training program arranged to support the learning process which will lead to the aging development of the children. From the research, it was found that the children who received skill practice in the early years can learn better than those who enter the training program later. Once diagnosed as the intellectual disability such as down syndrome or high risk to be the intellectual disability, for example, premature birth, mother was bleeding while giving birth, etc the program will be immediately applied and no need for the child to stay in the hospital. The development enhancement program is to set the environment to support the learning process of children. Parents and nanny have the important role in development of the child. The achievement thus depends on the cooperation and seriousness of the family members rather than the professional staff.
Physical therapy
The children with intellectual disability usually have problem with motor development delay. For those who have severe and profound severities mostly have the central nervous system handicap which results in the hardening of leg, arm, and body. The treatment shall be given to correct the abnormal movement to reduce stiffness of joint and muscle loss and the child will better help themselves when they are older.
Occupational therapy
Training to use the fine motor, i.e. holding and grasping things, practice the eye-hand co-ordination. The child can hold the cup of water, hold toothbrush, spoon, occupational cure, in order for him/her to live their life more comfortable and convenient.
Speech therapy
More than 70% of the children with intellectual disability have the difficulty of speaking and communication. Training on this concern not only for them to pronounce the voice understandable by general people but also to practice using the speaking muscles, control the voice muscles, pronounce correctly. The training shall be conducted before the age of 4 years old.
2. Educational Rehabilitation
In the past two decades, the belief that education means learning to live the life well outside school has made the educational rehabilitation of the people with intellectual disability differ from what had been conducting. Years after years after the academic learning it was found that the knowledge is not practical to the people with intellectual disability. The education therefore shall support the normal living of disability among the normal people. Normal people and people with intellectual disability shall have their opportunity to share and learn in the same classroom, same education for as much as possible. Classroom, curriculum, and evaluation management must be reformed for the people with intellectual disability their opportunity to study not to weed them out. Special Education for only the people with intellectual disability shall be only with ultimate necessity. The Integration and Inclusion Education must be promoted.
3. Vocational Rehabilitation
The profession preparation for people of ages 15-18 years old with intellectual disability is very important to them when they are adult. The learning or training shall composes of punctuality, order following, interaction among colleagues and social etiquette. These people are appropriate for many works such as housework, servicing works, factory works, office work document service, photocopying, etc.
Recommendations
The top goal of teaching people with intellectual disability is to have them to live their life as well as normal people do. The success will be dependent on the following factors:
1. Severity of the intellectual disability that is one who has mild level has his/her great opportunity to develop their capability better than one with moderate or severe level.
2. Side effects will be the obstacles to the physical rehabilitation which will result in the less success.
3. Development enhancement which is given at the earlier age would be better than when given at the older age.
4. The cooperation of the childs family, the family plays an important role in helping the child with intellectual disability for all his/her life long. The family shall be prepared to understand the handicap, capability limitation, special need of the child including expectation from the child. The way of caring is also crucial and the family members are playing an important role.
People with intellectual disability can learn and live their life happily and equally in the same community with normal people. The community shall open for and assist these people as appropriate so that people with intellectual disability can live their life with dignity and value.
Prevention
The intellectual disability can be prevented by the following;
1. Pre-pregnancy period people, in general, shall have the knowledge about the intellectual disability and the preventable causes, for example, German measles vaccination or iodine provision; provide useful knowledge to the marriage couple about the appropriate age of mother when gets pregnant (19-34 years old) and the interval of time to the next child (2 years), the genetic diseases diagnosable prior to the pregnancy or birth giving including the family planning.
2. Pregnancy period the prenatal care shall be performed at the health station or hospital to prevent any risks and mother will be fully vaccinated as necessary and sufficient nutrients. Avoid drinking, smoking, drug use including taking medicine without prescription that it may affect the baby. The mental health enhancement within the family and pre-birth diagnosis is recommended.
3. Birth giving period: shall give birth at the public health service in order to prevent various side effects.
4. Post natal period: the mother shall stay with the child as soon as possible so that the child can drink the milk from mothers breasts which riches with immunities and necessary nutrients. Be careful of jaundice, ensure to give the child vaccination, monitor the nutrition and development of the child, especially those with high risk. Inform the parents about the care during the illness time; to be careful for infection, toxic, and head impact, love and care to the child.
Assessment forms
IQ and development assessment tools
- Bayley Scales of Infant Development
- Wechsler Preschool and Primary Scale of Intelligence III
- Stanford-Binet Intelligence Scale (5th Ed)
- Kaufman Assessment Battery for Children II
- Wechsler Intelligence Scale for Children (WICS-IV)
Self-adaptive assessment tools
- Vineland Adaptive Behavior Scale II (VBAS II)
- AAMR Adaptive Behavior Scales-School (ABS-s II)
References
1. Noppawun Sriwongpanich, Patt Rojmahamongkol. Intellectual Disability/ Mental Retardation. in: Nichara Ruangdarakanon, Chacriya Theeranate, Rawiwun Rungpriwun, Tippawun Hussakhunachai, Nittaya Kochapakdee, Children behavior and development textbook, first published, Bangkok: Holistic Publishing, 2008: 179-204.
2. Noppawun Sriwongpanich. Knowing the Mental Retardation. In manual of How to Develop the Mental Retardation Curriculum for public health personnel, Rajanukul Institute, Department of Mental Health, 2007.
3. Chawala Thianthanu, Kalaya Sutabut. Mental Retardation. Copied document of Rajanukul Hospital Division, Department of Mental Health, Ministry of Public Health.1996.
