Diagnostic value of migraine biomarker — calcitonin-gene-related peptide

Abstract

Objective — to study the diagnostic significance of the serum level of calcitonin‑gene‑related peptide as a tool for the differential diagnosis of migraine with comorbid neck pain and tension of the pericranial muscles and cervicogenic headache. Methods and subjects. The study included 112 patients (84 women, 28 men) aged from 18 to 58 years. In 77 patients episodic migraine was diagnosed (with a typical aura in 17 and without aura in 60 patients), in 35 patients suffered from cervicalgia with muscle‑tonic syndromes and cervicogenic headache. Among patients with migraine, 42 had concomitant cervicalgia with muscle‑tonic dysfunction. The examined patients were distributed into 3 clinical groups: I — combination of episodic migraine with cervicalgia, II — episodic migraine, III — cervicalgia without migraine. In all patients, pain intensity was assessed using a visual analogue scale, the effect of migraine on daily activity and performance using the MIDAS and HIT‑6 scales, and the Neck Disability Index. The control group for comparing the serum level of CGRP consisted of 30 clinically healthy persons. The serum level of CGRP was determined by enzyme‑linked immunosorbent assay using the sandwich ELISA principle. Results. In the group of patients with a combination of episodic migraine with cervicalgia and cervicogenic headache, compared with the group with isolated migraine, the number of days with headache over the last 3 months was higher (р < 0.001), the influence of headache on daily activity and performance according to the MIDAS scales and HIT‑6 was more significant (both р < 0.001) and the number of combined analgesics used was higher (р < 0.001). Plasma level of CGRP was statistically significantly higher in patients with episodic migraine compared with the group with cervicalgia without migraine (р < 0.05), where it did not differ from the control. The CGRP level was statistically significantly higher in women with migraine compared to men (р < 0.001), but did not differ in patients with migraine with and without aura (р > 0.05). Conclusions. The serum level of calcitonin‑gene‑related peptide is a reliable diagnostic and differential diagnostic laboratory biomarker of episodic migraine. The presence of concomitant cervicalgia in patients with episodic migraine significantly affects the level of CGRP in the blood plasma and the course of the disease (an increase in the number of days with headache, the amount of analgesic use, decreased performance and daily activity).