Effectiveness, safety, and predictors of response to ultrasound-guided stellate ganglion blockades for the treatment of patients with chronic migraine: A retrospective and observational study.

BACKGROUND

Whether ultrasound-guided stellate ganglion block (SGB) is a valuable therapeutic option for the treatment of patients with chronic migraine (CM) is worth exploring. If SGB is proven to be effective for CM, the identification of potential predictors for the effectiveness of SGB warrants further investigation. This study aimed to investigate the effectiveness and safety of SGB in patients with CM and to explore the predictive factors for its treatment effectiveness.

METHODS

This is a retrospective observational study. We retrospectively analyzed the effects of SGB for the treatment of patients with CM under ultrasound guidance, between January 2018 and June 2022. The follow-up time was approximately 1 month, 2 months, and 3 months after the last SGBs. The response criterion was defined as a reduction in pain intensity of > 50% measured using the most severe numerical rating scale (NRS) score compared to pretreatment baseline, without an increase in the dose or the type of analgesic or anxiolytic/antidepressant medication, otherwise unresponsive to SGB. Univariable and multivariable analyses were performed to identify the predictive factors for SGB response.

RESULTS

Ninety-seven patients were included in this study. SGB was effective in most of the CM patients, with an effective rate of 90.7%, 82.5%, and 71.1% after 1, 2, and 3 months of the last SGBs, respectively. At 3-month follow-up, 95.7% responsive patients benefited from repeated SGBs. In patients receiving repeated SGB treatments, the number of SGBs in responsive patients was significantly greater than those in patients with no response at 3-month follow-up (3.41 ± 1.31 vs. 2.68 ± 0.67, p = 0.02). Comorbid anxiety or depression was a negative predictor of SGB effectiveness at 3-month follow-up (B = -0.25, 95% CI -0.45 to -0.05, p = 0.01). The overall adverse events rate associated with ultrasound-guided SGB was 9.3%. There were no serious complications; all adverse events were transient, with hoarseness being the most common adverse event.

CONCLUSIONS

Ultrasound-guided SGB was an effective and safe treatment for CM patients. The majority of responsive patients with CM benefited from repeated SGBs. CM patients who needed repeated SGBs may obtain good and sustained analgesic effect after receiving a greater number of SGBs. Patients without comorbidities such as anxiety or depression were more likely to benefit from SGB treatments.