The trend is encouraging, researchers say, because current guidelines recommend against using the drugs, benzodiazepines, to treat symptoms associated with posttraumatic stress disorder (PTSD).

"One of our concerns is that it's very, very difficult to get patients off benzodiazepines," said Dr. Matthew Friedman, executive director of the National Center for PTSD and a professor of psychiatry at Dartmouth, who co-authored the study.

Benzodiazepines include the medications alprazolam (Xanax), diazepam (Valium) and clonazepam (Klonopin). They are used to manage conditions such as anxiety and insomnia, which are often linked to PTSD. Long-term use of the drugs can lead to high tolerance and addiction.

The study, which looked at data from more than 498,000 patients in the Veterans Affairs health care system between 1999 and 2009, found decreases in the frequency, duration and doses of benzodiazepines given to veterans with PTSD.

Treating veterans with PTSD will become even more important in coming years, the team notes, due to recent and ongoing U.S. military conflicts. The number of veterans with PTSD treated in the Veterans Affairs health care system rose nearly 200 percent between 1999 and 2009.

The percentage of PTSD patients given benzodiazepines fell from about 37 percent in 1999 to about 31 percent in 2009. Of patients taking the drugs, the proportion of long-term (more than 90 days) users dropped from about 69 percent in 2000 to about 64 percent in 2009. Daily doses fell 14 percent on average, according to findings published in the Journal of Clinical Psychiatry.

Veterans with PTSD have an increased risk for harm because they often also suffer from substance abuse disorders, the researchers note. Estimates place the co-occurrence of alcohol abuse and PTSD around 25 percent, or higher, nationally.

Emerging evidence also suggests benzodiazepines may interfere with prolonged exposure therapy, which has been one of the most effective treatments for PTSD, Friedman said.

Guidelines issued by the departments of Defense and Veterans Affairs earlier this year recommend against using the drugs to treat veterans with PTSD. Instead, experts generally recommend psychotherapy to treat core symptoms such as hypervigilance, avoidance and flashbacks. The guidelines also recommend using antidepressant medications to treat PTSD symptoms.

"We believe a lot of benzodiazepines are being prescribed for problems with sleep, which is also a symptom of depression," Friedman told Reuters Health. "If we treat the depression, perhaps the insomnia will also go away."

The study found that new PTSD patients -- those who were diagnosed and began treatment at a Veterans Affairs medical center -- in 2009 were prescribed benzodiazepines at the lowest rate, about 21 percent. Newly diagnosed patients are often the first to benefit from updated treatment guidelines.

TRADING ONE RISK FOR ANOTHER?

But the possibility that benzodiazepines are simply being swapped out for other risky drugs concerns some experts.

Substituting more modern medications such as zolpidem (Ambien) or quetiapine (an antipsychotic) is not the answer, said Dr. Alexander Neumeister, a professor of psychiatry and radiology at New York University.

"Unfortunately, when you look into databases like the VA's, it is pretty evident that there is a lot of off-label use of medications like quetiapine to treat sleep issues," Neumeister told Reuters Health, referring to the ability of doctors to prescribe drugs approved for conditions other than PTSD.

"Even if you avoid the abuse problem, you're nevertheless treating a patient with a medication that really should not be used for that indication. Not at all."

The study authors also recognized that possibility.

"We are trying to characterize these diagnoses to get a better handle on who's prescribing what, who's getting what, and for what reasons," said Friedman. "Based on that information, we can develop our educational approaches to inform clinicians who may not be as familiar with clinical practice guidelines."

SOURCE: bit.ly/rAcuOG Journal of Clinical Psychiatry, online November 29, 2011.

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