Therapeutic effectiveness and safety profile of steroid-based greater occipital nerve blocks in cluster headaches: a systematic review and meta-analysis.

BACKGROUND

Cluster headaches (CHs), including episodic (ECH) and chronic (CCH) forms, are intensely painful and disabling, with limited preventative options. Greater occipital nerve blocks (GONBs) are frequently used in practice; however, the safety and efficacy of steroid-based injections, alone or combined with local anesthetic in CH patients, remain unclear.

OBJECTIVE

To evaluate the efficacy and safety of corticosteroid-based GONBs, with or without local anesthetic, in patients with CHs, including ECH and CCH. Outcomes included attack frequency, proportion of responders, duration of effect, pain reduction, and adverse events.

EVIDENCE REVIEW: We systematically searched Cochrane, Embase, Emcare, PubMed, and PsycInfo from inception to March 24, 2025 for eligible studies involving patients with CHs who received GONBs stratified by corticosteroid use. Data were narratively synthesized, with random-effects meta-analyses performed: a proportional meta-analysis of GONB arms, and a binary meta-analysis of randomized studies comparing GONBs versus control (saline±local anesthetic). Subgroup and risk of bias (RoB) sensitivity analyses were conducted for ECH and CCH. RoB was assessed using the Cochrane RoB 2.0 and ROBINS-I tools. Certainty of evidence was assessed using Grading of Recommendations Assessment, Development, and Evaluation. Protocol registered on OSF (https://doi.org/10.17605/OSF.IO/6EAZN). No funding was received.

FINDINGS: Nineteen studies were included, comprising 758 CHs, 324 ECHs, and 375 CCH patients. All studies suggested improvements in outcomes with particulate steroid-based GONBs. Pooled data showed similar efficacy between single and multiple injections, with mostly minor, transient adverse events and consistent reductions in pain across studies. Mean duration of effect was 43 days (CH), 61.6 days (ECH), and 32.2 days (CCH). Proportional meta-analyses explored probabilities of response: CH=73%, ECH=77%, CCH=69% (I²=86.5%, 47.8%, 89.9%). Sensitivity analyses provided similar estimates: CH=79%, ECH=75%, CCH=70%. Binary meta-analyses showed non-significant reductions in attack frequency for CH (p=0.06) and ECH (p=0.11), and a significant reduction for CCH (p=0.01, relative risk=2.67, 95% CI 1.24 to 5.75). Adverse events did not differ between groups (p=0.43).

CONCLUSION

Particulate steroid-based GONBs show promise for CH treatment by decreasing attack frequency, while mostly producing short-term adverse events. The evidence quality spans from very low to moderate.