TUESDAY, Sept. 30 (HealthDay News) -- People with complex mental disorders or personality disorders would benefit from long-term psychodynamic psychotherapy that lasts at least a year or longer, according to new research.

Published in the Oct. 1 issue of the Journal of the American Medical Association, the German study found that compared to the more commonly used short-term therapy, long-term psychotherapy left people better off. In fact, the number of therapy sessions the patients had was directly correlated to improvements in symptoms.

"Long-term psychodynamic psychotherapy was significantly superior to shorter forms of psychotherapy applied in the control groups. This was true with regard to overall effectiveness, target problems, and personality functioning," said the study's lead author, Falk Leichsenring, a professor of psychotherapy research in the department of psychosomatic medicine and psychotherapy at the University of Giessen in Germany.

"With regard to overall effectiveness, on average, patients with complex mental disorders were better off after treatment with long-term psychodynamic psychotherapy than 96 percent of the patients in the comparison groups. Thus, this meta-analysis provides evidence that long-term psychodynamic psychotherapy is an effective treatment for complex mental disorders," said Leichsenring.

"This study provides a great value for doctors and for patients, and one would hope could have an influence on policy decisions," added Dr. Charles Goodstein, a clinical professor of psychiatry at the New York University School of Medicine and Langone Medical Center in New York City.

Complex mental disorders include problems such as depression or anxiety that continue for long periods of time. Psychodynamic therapy, according to Leichsenring, is therapy that puts the focus on the therapist-patient relationship and the importance of developing that relationship. Leichsenring said this is a key difference between this type of therapy and some of the shorter-term options, such as cognitive behavioral therapy.

Leichsenring and his colleague, Sven Rabung, from University Medical Center Hamburg-Eppendorf, reviewed the medical literature to find studies that compared long-term psychodynamic therapy lasting a year or more to other forms of therapy. They found 23 studies with 1,053 patients. Eleven of the studies were randomized, controlled trials, and 12 were observational studies.

Overall effectiveness, resolution of the target problem, and personality functioning were superior in the long-term psychodynamic therapy groups than in the comparison groups, according to the analysis.

The bottom line: "Long-term psychodynamic psychotherapy is superior to short-term treatments in patients with complex mental disorders," Leichsenring said.

But the problem, according to Goodstein, is that insurance companies often don't want to pay for long-term therapy, perhaps believing medications and short-term therapy are more cost-effective options.

For someone who's just started having symptoms -- considered an acute problem -- short-term therapy may be helpful, according to Goodstein. But, for those who've had mental health symptoms chronically, short-term therapy may boost them to a "barely livable level" but not to a good quality of life.

So, what's the ideal number of visits? It really depends on the individual and their specific problem, but Leichsenring said, "there is evidence that most patients with acute distress benefit sufficiently from 25 sessions. For patients with chronic distress, about 50 sessions are required to achieve a response rate of 70 percent. For patients with personality disorders, there is evidence that about 200 sessions, or 2 years of treatment, are required to achieve recovery in 75 percent of the patients."

More information

To learn more about psychotherapy, including psychodynamic psychotherapy, visit the America Psychiatric Association's Healthy Minds Web site.