ADHD is not usually expressed as an isolated entity . Many children with ADHD (65%) present with one or more mental and developmental disorders (comorbidities) that often complicate the course and management of the disorder per se. The incidence of comorbids in the adult population with ADHD is much higher reaching 75%.
The most common ADHD comorbidities are the following :
- Oppositional defiant disorder and conduct disorder
- Mood disorders
- Learning disabilities (dyslexia, misspelling, and dyscalculia)
- Special developmental disorders (speech disorder, movement coordination)
- Emotional disturbances
- Tics (Tourette’s syndrome) etc
Children with ADHD, particularly those who have not been diagnosed and treated at an early stage, have several difficulties that are expressed at school, at home or at the social environment which very often may result in:
- Lower academic achievements compared to the level of their cognitive abilities and academic failure
- Increased stress, emotional disorders and low self-esteem
- Aggressiveness and disruptive behaviour or conduct problems
- Limited professional productivity and prospects
- Rejection by others and dysfunctional social relations
In adults, ADHD has been associated with significantly higher arrest rates, antisocial, destructive and addictive behaviour, particularly, in individuals who presented with conduct disorders in childhood.
ADHD has been associated with delinquency in adulthood, especially when there is comorbid conduct disorder in childhood or substance abuse and antisocial personality disorder in adulthood.