Intellectual and Developmental Disorders (IDD)

IDDs are conditions typically present at birth and that uniquely affect the trajectory of a child’s physical, intellectual, and/or emotional development through adolescence and adulthood. Intellectual disability (ID) occurs before a child turns 18 and is characterized by differences with both intellectual ability (i.e., functioning or intelligence including the ability to learn, to reason, and to problem solve among other skills) and adaptive behaviors (i.e., everyday social and life skills). There are four levels of ID: Mild, Moderate, Severe, and Profound. Intellectual disabilities can be caused by a known syndrome, injury, stroke, or illness. Common causes of ID include: Down Syndrome, Fragile X Syndrome, Prater-Willi Syndrome, and Rett Syndrome. ID can also co-occur with ASD. In 30-50% of cases, the cause of ID is unknown or idiopathic. Developmental disability (DD) is a broader term for disorders that impact intellectual or physical functioning, and in some cases both.

Because of its interrelatedness to illnesses and disorders, diagnosis for IDDs often incorporates medical or genetic testing. Diagnosis of IDD requires a qualified mental health professional to gather information about the child, their behavior, and environment. No single test can diagnose a child as having IDD, and other problems, like language and communication disorders, can have similar symptoms. IQ and adaptive skills tests are core components of IDD evaluations. Evaluations include a combination of in-office testing procedures; questionnaires completed by parents, teachers, and children; and clinical observations. Often, mental health providers recommend evaluations with Occupational Therapists, Physical Therapists, and/or Speech Language Pathologists for further diagnostic clarity. Collaboration with the child’s medical care provider is essential. During the evaluation process, it is important to also understand the child’s strengths and interests as leveraging these can increase the effectiveness of interventions. Recognizing IDD symptoms and seeking help early will lead to better outcomes for both affected children and their families.

The type, duration, and frequency of supports will vary depending on each child and their specific presentation of IDD. Evidence-based supports include school-based Individualized Education Programs (IEPs) that can modify education and provide services as appropriate. Often children with IDD benefit from occupational therapy where they learn daily living skills. Mental health providers can treat symptoms of depression, anxiety, and other mental health disorders that may arise, in addition to bolstering social skills. Family therapy is often beneficial for families to alleviate stress and promote a healthy family system. Behavioral therapy is often recommended to support expressive communication, manage behaviors, establish routines, and teach social skills. In cases with co-occurring physical challenges, physical therapy may be appropriate. Explore the mental health services provided by the WCP team.

Other posts about IDD can be found on the WCP blog.

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