Comorbidity
Comorbidity refers to the presence of more than one diagnosis occurring in an individual at the same time. Evidence has shown that the brains of individuals with ADHD show functional, structural, and neurochemical differences in regions that support vital cognitive functions (Biederman, 2005). ADHD is a foundational disorder that substantially increases a person’s risk of experiencing additional cognitive, emotional, or behavior disorders (Brown, 2009) resulting in a severe impairment of everyday life with considerable functional and psychosocial problems (Taurines et al, 2010).
ADHD may be accompanied by mood disorders, learning disorders, substance abuse, sleep disorders, obsessive-compulsive disorder, autism spectrum disorders, oppositionality and aggression, Tourette syndrome, and developmental coordination disorder (Brown, 2009). Individuals with persistent ADHD had higher risks for anxiety disorders, particularly specific phobia, and are more likely to have Oppositional Defiance Disorder (Gau et al, 2010). Higher rates of co-occurrence/co-existence than expected by chance have also been documented between ADHD and atopic eczema, enuresis, encopresis, and developmental dyslexia. The majority of comorbidity appears after the onset of ADHD. Post-comorbidity includes tic disorder, depression, bipolar disorder, conduct and substance use disorders, obesity and personality disorders (Taurines et al, 2010).
