Aetiology of intellectual disability: general issues and prevention

Intellectual disability can follow any of the biological, environmental, and psychological events that are capable of producing a decline of cognitive functions. Some factors do not directly or inevitably cause intellectual disability but add to the effects of a previous primary cause. Genetic causes may be hereditary or non-hereditary, and may or may not produce specific syndromes. Some lead to inborn errors of metabolism. Causation, how to assess cause, and why knowledge of causation is important is covered in detail, followed by primary, secondary, and tertiary prevention, ethical problems of prevention, and the important of taking preventive aspects into account in all general and specific legislation, in operating procedures, and professional practice.