According to NAMI, “anxiety disorders are the most
common mental illnesses in America: they affect around 20
percent of the population at any given time” (2012). These
disorders touch approximately 40 million adults in the United
States per year, and persist for at least six months without
treatment. It is common for other illnesses such as substance
abuse and depression to exist alongside anxiety disorders and
to require treatment before the anxiety can be properly managed.
According to Halter, Varcarolis, and Shoemaker (2010),
anxiety occurs simultaneously with major depression 60% of
the time, with anxiety generally occurring first.