Scientists Probe PTSD Effects, Treatments

Abstract

San Diego—As a new generation of soldiers returns home bearing psychological scars of war, interest in and support for research on disorders such as posttraumatic stress disorder (PTSD) are high. At the Society for Neuroscience’s annual scientific meeting in November, researchers presented more than a half dozen studies probing the disorder. The studies’ findings included a biomarker that may one day help identify individuals with the disorder, enhanced explanations of how trauma may alter brain function, the discovery of intergenerational effects of trauma, and a drug that helped prevent PTSD-associated damage in rats. While many of the results are very preliminary, this recent spurt of research is a promising sign in a field that lacks validated treatment options despite a tremendous and growing demand for therapy. According to the National Institute of Mental Health, more than 5 million individuals in the United States have PTSD in any given year. A recent Institute of Medicine panel, which reviewed about 200 studies of therapies for the disorder, failed to find sufficient evidence of efficacy to recommend most of the currently used treatments (http://www.iom.edu/CMS/3793 /39330/47389.aspx). Exposure-based therapies were the only option found to have sufficient scientific support. The panel noted that many studies lacked sufficient quality to judge the effectiveness of various interventions and that there is an urgent need for high-quality trials of both pharmacological and behavioral interventions for PTSD. SEX AND GENERATIONAL EFFECTS Epidemiological studies have consistently found that PTSD is more prevalent in women than men (Olff M et al. Psychol Bull. 2007;133[2]:183-204). Rachel Yehuda, PhD, of the Traumatic Stress Studies Program at Mount Sinai School of Medicine, in New York City, discussed this and other sex-related issues in PTSD during a symposium on sex differences in stress response at the meeting. Yehuda explained that this higher prevalence may reflect women’s higher likelihood of experiencing the types of trauma that lead to PTSD, rather than greater biological vulnerability. For example, about half of individuals who have been raped develop PTSD, and women are 10 times more likely than men to be raped, she said. Sex-based differences in general stress response have been documented, and some evidence suggests there may be differences between men and women with PTSD. For instance, individuals with PTSD who have been raped tend to respond better to cognitive behavioral therapy than do combat veterans with PTSD, she said. “We need to ask whether gender differences in PTSD are simply a carryover of gender differences in stress response, or whether the actual experience and biology of PTSD is different [in men and women],” she explained. Additionally, evidence suggests that having a mother who has had PTSD may increase an individual’s risk of developing the disorder. Yehuda and her colleagues recently probed the potential biological basis of this enhanced vulnerability. The study examined cortisol levels in relation to circadian rhythms in 23 individuals who had at least 1 parent who was both a Holocaust survivor and had PTSD, 10 individuals who had at least one Holocaust survivor parent and no parent with PTSD, and 16 controls (Yehuda R et al. Arch Gen Psychiatry. 2007;64[9]:1040-1048). None of the participants themselves had PTSD. The researchers found that individuals whose mothers had PTSD were more likely to have low cortisol levels and other alter-