Dual Stellate Ganglion Blocks for Managing Treatment-Resistant Anxiety Disorder: A Randomized, Double-Blind, Placebo-Controlled Trial.

Anxiety disorders are associated with a high burden of illness. In patients with treatment-resistant anxiety disorder, management options can be limited. Stellate ganglion block has been reported to reduce anxiety symptoms in Posttraumatic Stress Disorder. We aimed to determine dual stellate ganglion block's effectiveness for reducing anxiety symptoms in moderate to severe treatment-resistant anxiety disorder. This double blinded, sham procedure, randomized controlled trial used a 2:1 active treatment to sham (control) treatment ratio. Pain Medicine clinic at Sri Madhusudan Sai Institute of Medical Sciences & Research, a tertiary care medical college in the Republic of India. Study patients were screened by an interdisciplinary team comprising a pain medicine physician, a psychiatrist, and a clinical psychologist. Participants and assessors were blinded. Adult patients with treatment-resistant moderate to severe anxiety disorder (a Generalized Anxiety Disorder-7 [GAD-7] scale score of ≥ 10) were included in the study. Patients with Posttraumatic Stress Disorder were excluded. Patients received either dual ultrasound-guided stellate ganglion blocks or a sham treatment. The primary outcome measure was the GAD-7 scale score at postintervention week 4. Of 87 screened individuals, 63 were eligible (72.4%); 20 were men and 43 were women; mean (SD) age, 38.4 (10.3) years. They were randomized (42 to the Stellate Ganglion Blocks Group and 21 to the Control (Sham) Group; 62 (98.4%) completed the study. In an intent-to-treat analysis, the mean total GAD-7 score change at postintervention week 4 was -9.6 points for the Stellate Ganglion Blocks Group, compared with -3.6 points for those receiving the sham/control treatment (mean difference -6.2; 95% CI,-9.3 to -3.2; P < 0.001). This was a single-center study with a limited follow-up period. In this trial of patients with treatment-resistant anxiety disorder, dual stellate ganglion blocks were effective in reducing GAD-7 scores for 12 weeks postintervention. Further studies are recommended to assess the durability beyond 12 weeks and elucidate the mechanism of action of stellate ganglion block.