Underlying Hippocampal Mechanism of Posttraumatic Stress Disorder Treatment Outcome: Evidence From Two Clinical Trials.

Background: The hippocampus plays an important role in the pathophysiology of posttraumatic stress disorder (PTSD) and its prognosis. Accumulating findings suggest that individuals with larger pretreatment hippocampal volume are more likely to benefit from PTSD treatment, but the mechanism underlying this effect is unknown. We investigated whether further increase in hippocampal volume during treatment explains the better prognosis of individuals with greater pretreatment hippocampal volume. Methods: We collected structural magnetic resonance imagesfrom patients with PTSD before and after treatment. We examined whether larger hippocampal volume moderates the effect of increased hippocampal volume during treatment on symptom reduction. Given the relatively small sample sizes of treatment studies with pre- and posttreatment magnetic resonance imaging, we focused on effect sizes and sought to replicate findings in an external sample. We tested our hypothesis in study 1 (N = 38; prolonged exposure therapy) and then tested whether the results could be externally replicated in study 2 (N = 20; ketamine infusion followed by exposure therapy). Results: Findings from study 1 revealed that increased right hippocampal volume during treatment was associated with greater PTSD symptom reduction only in patients with greater pretreatment right hippocampal volume (p = .03; η2 = 0.13, a large effect). Findings were partially replicated in study 2 for depressive symptoms (p = .034; η2 = 0.25, a very large effect) and for PTSD symptoms (p = .15; η2 = 0.15, a large effect). Conclusions: Elucidating increased hippocampal volume as one of the neural mechanisms predictive of therapeutic outcome for individuals with larger pretreatment hippocampal volume may help identify clinical targets for this subgroup.

Oxytocin as a Biomarker of Differential Effects to SPACE vs. CBT Treatment of Child Anxiety Disorders.

OBJECTIVE: Two lines of research, on outcome moderators and on novel treatment targets, seek to improve the overall efficacy of child anxiety treatment, with mixed results. We propose that an integration of both lines of research can lead to improved treatment efficacy. In a first proof of concept of this approach, we studied whether the interaction between baseline levels and targeted changes in peripheral oxytocin (OT) can predict differential responses to two childhood anxiety treatments. METHOD: A total of 124 mother-child dyads participated in the study. Children's salivary OT levels were measured at baseline and again, immediately after an experimental dyadic interaction in the lab. Dyads were subsequently randomized to receive one of two treatments, differing in their targets: SPACE (Supportive Parenting for Anxious Childhood Emotions) and CBT (cognitive-behavioral therapy). Treatment outcomes were assessed using the Childhood Anxiety Related Emotional Disorders scale, reported by both mother and child. RESULTS: The findings suggest that in SPACE, where the mother is the main agent of change, higher baseline levels of child OT, coupled with increases in OT following a positive mother-child interaction, predicted greater treatment efficacy. By contrast, in CBT, where the child is the main agent of change, higher baseline levels of child OT, coupled with a decrease in OT following the interaction, predicted greater treatment efficacy. CONCLUSIONS: The findings highlight the importance of the integration between moderators and targets of treatments for progress toward improving treatment efficacy through precision medicine.

Religiosity, Meaning in Life and Suicidal Tendency Among Jews.

UNLABELLED: The study examines the impact that meaning in life, or lack thereof, has on suicidal tendencies among youth, as well as the nexus between level of religiosity, meaning in life and suicidal tendencies. Subjects were 450 students from both Jewish religious and Jewish secular schools aged 15-18. FINDINGS: a significant and negative correlation was found between a sense of meaning in life and suicidal tendencies, beyond gender or level of religiosity. In addition, no difference was found in level of suicidal tendency between Jewish religious and Jewish secular youth; however, among Jewish religious teens, a lower level of depression was reported in comparison with their secular peers. The study therefore concludes that meaning in life is the dominant variable in minimizing suicidal tendencies among youth. The results of this study may promote the establishment of prevention, intervention and therapy plans, especially in the age range that is crucial for suicide. Such programs should be based upon finding meaning in life.