Yale School of Medicine will direct a $6.9 million nationwide study into the effectiveness of an anti-psychotic medication for veterans with chronic, military service-related post-traumatic stress disorder (PTSD).

The Yale-led study is funded by the U.S. Department of Veterans Affairs. It is the first multi-center trial to evaluate a non-SRI treatment for PTSD symptoms and the first multi-center study of the medication treatment of PTSD to focus on veterans.

PTSD is the most prevalent and costly psychiatric diagnosis treated within the U.S. Department of Veterans Affairs, said John Krystal, M.D., professor in the Department of Psychiatry at Yale School of Medicine. He said there are an estimated 196,000 veterans with PTSD. Five percent of all Veterans Administration (VA) patients and 25 percent of all patients with mental health diagnoses have a diagnosis of PTSD. Thirteen percent of all VA mental health costs, or $274 million, is spent to care for veterans with PTSD.

"Recent survey data suggest that 10 to 20 percent of soldiers participating in combat in Iraq meet criteria for PTSD," Krystal said. "Thus, there is good reason to anticipate a substantial influx of veterans with PTSD into VA treatment programs."

Currently, there are only two medication treatments approved by the U.S. Food and Drug Administration for the treatment of PTSD and both are in the same class of antidepressant, the serotonin reuptake inhibitors (SRI's).

"Although antidepressants are the most commonly prescribed medications to treat PTSD symptoms, these medications often have limited effectiveness for veterans with long-standing PTSD symptoms related to their military service," said Krystal. "The study will determine whether an 'atypical' antipsychotic drug, risperidone, is effective for treating PTSD symptoms in veterans who have not responded to antidepressant treatment. It builds on emerging evidence that atypical antipsychotic drugs may be important new medications for treating PTSD symptoms that are unresponsive to antidepressants."

Krystal and Robert Rosenheck, M.D., also a professor of psychiatry at Yale, will direct the study from the VA Connecticut Healthcare System in West Haven. Krystal also leads the Clinical Neuroscience Division and Rosenheck heads the Evaluation Division of the VA's National Center for PTSD.

Four hundred veterans with chronic, military service-related PTSD will be enrolled at 20 VA hospitals from across the United States over a two-year period. Half of the patients will receive risperidone and half will receive placebo for six months. The primary objective is to determine whether PTSD symptoms are reduced by risperidone. This study also will evaluate whether other consequences of PTSD will respond to risperidone, including sleep disturbance, violent behavior, cognitive impairment, alcohol and substance abuse, and reduced quality of life. It will also explore whether it is safe and cost-effective to prescribe risperidone to veterans with PTSD.

"PTSD is an important and timely focus for VA research," Krystal said. "The Vietnam Veterans Readjustment Study, published in the early 1990s, showed that more than 15 percent of a nationwide sample of veterans still had sufficient symptom levels to meet diagnostic criteria for PTSD 15 yeas after the end of the Vietnam War. New cases of PTSD have been associated with each successive U.S. military engagement and peacekeeping mission since the Vietnam War. This new study may help to address an important unmet need for these veterans, their families, and the VA."

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