Treatment seldom hinges on which disorder came first. "In many cases," says Ross, "the depression exists because the anxiety is so draining. Once you treat the anxiety, the depression lifts."
In practice, treatment is targeted at depression and anxiety simultaneously. "There's increasing interest in treating both disorders at the same time," reports Himle. "Cognitive behavioral therapy is particularly attractive because it has applications to both."
Studies show that it is effective against both. But sometimes the depression is so incapacitating that it has to be tackled first. Depression, for example, typically interferes with exposure therapy for anxiety, in which people confront in a graduated way situations they avoid because they give rise to overwhelming fear.
"Exposure therapy requires substantial effort," explains Himle. "That's effort that depressed people often do not have available to them." Antidepressants can make a difference. Most SSRIs are approved for use in anxiety disorders and are the first line of drug therapy. But which drug works best for whom can not be predicted in advance. It takes some trial and error.
Ross finds CBT 80-90% successful in getting people functioning well, "provided it's done correctly." Not all psychotherapy is CBT, which has a very specific set of procedures, nor is every mental health professional trained in CBT. "Patients have to make sure that is what they are really getting."