Depression
NO
Obsessive Compulsive disorder
If I understand the question, then you would be able to work if you suffered from Borderline Personality Disorder. The Mental Health Act 2007 ensures that people who suffer from mental illness have equal rights with regards to employment.
Post Traumatic Stress Disorder (PTSD)
split personality disorder
No. This is a mental disorder and animals do not operate on a sufficiently high enough level cognitively or intellectually to be plagued with such. EDIT: GID is not a mental disorder.
It is theorised that about 100 million people in the world suffer from mental ill-health, although there is no way of knowing or proving that this theory is true.
obsessive-compulsive disorder
Arrogance and you don't have to be a mental patient to suffer from it.
That is a interesting question. The South Carolina Mental Health Department states that 1 out of 200 Americans suffer from some type of eating disorder making it a total of over 8 million Americans.
We are not sure of what you mean. If you are asking about bipolar disorder and attention deficit disorder being present together, it is quite common. You should be speaking to a mental health professional about it if you have these problems. They are both treatable (sometimes with the same medication) and you do not have to suffer.
Depression is not only a common mental disorder, but one of the single most common. Somewhere around one in five men suffer from depression, and one in three women.