Intellectual and learning disabilities

What is intellectual disability? 

An intellectual disability is impaired intelligence that is measured by an IQ lower than 70. Intellectual disabilities usually present during the first eighteen years of life and may also be known as an intellectual handicap, developmental disability or learning disability. Down Syndrome and Fragile X Syndrome are common causes of intellectual disabilities. It has been suggested that there is an increased risk of psychotic disorders in people with an intellectual disability. Antipsychotic medication is most commonly used to treat people with schizophrenia and intellectual disability, however there is often concern about the detrimental effects of antipsychotics on learning and cognition, and the long-term physical side effects.

What is the evidence for intellectual disability?

Moderate to high quality evidence suggests the prevalence rate of schizophrenia in people with an intellectual disability is around 3.5%. The rate is slightly higher in females and higher in mild cases of intellectual disability than in moderate or severe cases.

Moderate quality evidence suggests people with schizophrenia and mild/borderline intellectual disability may have more negative symptoms of schizophrenia than people with schizophrenia and no intellectual disability

April 2019

Last updated at: 4:27 am, 23rd April 2019
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