Depression, anxiety, and other conditions often accompany ADHD in adults.
If you have ADHD, consider screening for common co-morbid traits.
ADHD occurs in 3% to 5% of the US population. The risk for comorbidity is high, and the presence of comorbid disorders warrants special consideration in the treatment of patients with ADHD. For example, a comorbid diagnosis of ADHD and depression occurs in approximately 20% to 30% of patients, and ADHD and anxiety in more than 25% of patients.
from What Are Common Comorbidities in ADHD (Psychiatric Times); Julie Sherman, PhD and Jay Tarnow, MD (July 26, 2013)
It estimated the prevalence of ADHD to be 4.4% in 18- to 44-year-olds. Comorbidity rates were significantly elevated in this group compared to adults without ADHD. Respective rates were: mood disorders 38 and 11% (p < 0.05); anxiety disorders, 47 and 19% (p < 0.05); SUD, 15 and 6% (p <0.05), and intermittent explosive disorder, 29 and 6% (p < 0.05). Among the mood and anxiety disorders, all the individual component disorders were significantly elevated in the ADHD adults. Not so in the case of SUDs – only drug dependence was significantly higher in the adults with ADHD (4.4 vs. 0.6%, p < 0.05). There were no significant differences in alcohol abuse, alcohol dependence, and drug abuse.
from Attention-Deficit Hyperactivity Disorder (ADHD) in Adults. Key Issues in Mental Health; Rachel G. Klein, ed. (2010)