November 15, 2019
By Marilynn Larkin
NEW YORK (Reuters Health) - Two stellate ganglion block (SGB) treatments two weeks apart reduced posttraumatic stress disorder (PTSD) symptoms in a multisite randomized clinical trial of US veterans.
"The stellate ganglion is like a routing center for the nervous system and partially controls the impulse for fight or flight," Kristine Rae Olmsted of RTI International in Research Triangle Park, North Carolina explained in an email to Reuters Health. "Anesthetizing the ganglion blocks nerve impulses temporarily."
"We still don't know how an SGB works to improve PTSD symptoms, but now we know that it does," she said. "It's important that people understand SGB is not a cure for PTSD, but it's another option that we have for treatment. We hope to learn more about how long the effects last in a follow-up study we have planned."
Active-duty service members on stable doses of psychotropic medication who had a PTSD Checklist-Civilian Version (PCL-C) score of 32 or more at screening were included in the study. The intervention paired right-sided SGB or sham procedures at baseline and at week 2.
The primary outcome was the change from baseline to week 8 in overall total symptom severity scores on the Clinician-Administered PTSD Scale for DSM-5 (CAPS-5), which ranges from 0 to 80 points, with a 10-point change considered clinically significant.
As reported online November 6 in JAMA Psychiatry, 100 men and 13 women participated; 74 were randomized to SGB and 39 to sham. Baseline characteristics were similar between groups: the mean age at screening was about 37; most participants were about four years from the time of diagnosis/onset of symptoms; about 40% were taking antidepressants and 20%, anxiolytics. Mean CAPS-5 scores were also similar: 37.6 for the SGB group and 39.8 for the sham group.
One hundred and eight patients completed the study. In an intent-to-treat analysis, the adjusted mean total symptom severity score change was −12.6 points for the group receiving SGB, compared with −6.1 points with sham treatment.
With respect to secondary outcomes - differences from baseline in PTSD-related symptoms of depression, distress, anxiety, pain, and physical and mental functioning at week 8 - those receiving SGB had significantly improved assessment scores compared with sham treatment (mean, -12.63 for SGB vs. −5.16 for sham).
Six adverse events, none serious, were reported.
The authors conclude, "The mild-moderate baseline level of PTSD symptom severity and short follow-up time limit the generalizability of these findings, but the study suggests that SGB merits further trials as a PTSD treatment adjunct."
Rae Olmsted said, "As of now, the treatment is only available at a handful of US military and VA medical centers, as well as from one or two private providers. We are unsure of whether or when the treatment will be made more available to clinicians, though we hope they recognize SGB as a new treatment option for those suffering from PTSD."
Dr. Christopher Sobey, Pain Medicine Fellowship Program Director and Assistant Professor of Clinical Anesthesiology at Vanderbilt University Medical Center in Nashville, commented in an email to Reuters Health, "The study demonstrates a reasonable treatment option for patients with refractory PTSD symptoms in our veteran population, who have failed to receive significant improvement from medication and psychotherapy treatments alone."
"This study substantiates much of what we have seen in our practice regarding treatment of these veterans using SGBs in effectively reducing the severe symptoms of PTSD," he said. "SGBs can be considered as an adjunct second- or third-line treatment option."
"Given the potentially serious complications associated with the SGB procedure, I would caution those untrained in the details of the injection," he added. "Although there are potentially serious risks, in the care of a specialty-trained physician familiar with the procedure and anatomy of the region using image guidance, this should be considered a safe, viable, and promising treatment option for this vulnerable population."
JAMA Psychiatry 2019.(c) Copyright Thomson Reuters 2019. Click For Restrictions - https://agency.reuters.com/en/copyright.html