Most common mental disorder as a cause of suicide

Suicide is a model of psychiatric emergencies and is also the commonest cause of death among the psychiatric patient&;s psychiatric disorders are a major cause of suicide, for example, depression(1major depression 2depression secondary to a serious physical illness 3reactive depression), alcoholism and drug dependence and schizophrenia (Ref: a sho textbook of psychiatry, Niraj Ahuja, 7th edition, pg no.222)