what are some illnesses of mental health
1 18.1% of adults in the U.S. experienced an anxiety disorder such as posttraumatic stress disorder, obsessive-compulsive disorder and specific phobias. 2  7. 3  Among the 20.7 million adults in the U.S. who experienced a substance use disorder, 40.7%â8.4 million adultsâhad a co-occurring mental illness.