Meditation may also be helpful in the treatment of panic disorders. There was a meta-analysis of the comorbidity of panic disorders and agoraphobia. It used exposure therapy to treat patients over a period. Hundreds of patients were used in these studies and they all met the DSM-IV criteria for both of these disorders. A result was that thirty-two percent of patients had a panic episode after treatment. They concluded that the use of exposure therapy has lasting efficacy for a client who is living with a panic disorder and agoraphobia.