Changes in plasma CGRP levels and clinical outcomes following acupuncture in episodic migraine: a prospective pilot study (the AcuCGRP study)

Manual acupuncture is an established non-pharmacological treatment for migraine, with efficacy comparable to conventional prophylactic therapies. Calcitonin gene-related peptide (CGRP) plays a central role in migraine pathophysiology and has been proposed as a biomarker for treatment response. This study aimed to investigate changes in plasma CGRP levels in patients with episodic migraine undergoing a course of manual acupuncture.

Fifty-two patients with episodic migraine received 10 sessions of standardized manual acupuncture. Clinical assessments and plasma samples were collected at baseline and one week after treatment completion. The primary outcome was the change in plasma CGRP levels. Secondary outcomes included changes in migraine frequency, pain intensity, acute medication intake, and HIT-6.

No statistically significant change in plasma CGRP levels was observed (baseline: 60.9 pg/ml; after treatment: 62.4 pg/ml; p = 0.841). Significant clinical improvements were observed, in migraine frequency (median decrease of 1.5 days/month, p < 0.001), pain intensity (1-point decrease on a 10-point scale, p < 0.001), acute medication use (2 units/month, p < 0.001), and HIT-6 score (-6 points; p < 0.001).

This is the first study to investigate changes in plasma CGRP levels following acupuncture in patients with episodic migraine. While CGRP levels remained unchanged, patients experienced reductions in headache frequency, intensity, medication use, and disability. Although these improvements may be attributable, at least in part, to acupuncture, the single-arm design precludes causal inference. Peripheral plasma CGRP may not be a straightforward biomarker of clinical changes in this setting. Controlled studies are warranted.