The following is a summary of “Dynamic fluctuations of salivary CGRP levels during migraine attacks: association with clinical variables and phenotypic characterization,” published in the April 2024 issue of Pain by Alpuente et al.
Despite the role of Calcitonin gene-related peptide (CGRP) in migraine, its complex nature makes it a difficult biomarker for this neurological disorder.
Researchers conducted a retrospective study exploring fluctuations in salivary CGRP levels across the migraine frequency spectrum and identifying any associations with clinical features.
They enrolled patients with migraines from an outpatient headache clinic. Salivary CGRP levels were measured at interictal, onset, post-2 h of onset, and end-of-attack. Using generalized linear mixed models, they investigated CGRP changes during the attack, considering depressive symptoms (DS), acute attack treatment, and three-month erenumab treatment. Ultimately, patients were categorized and compared based on their CGRP phenotype.
The results showed that 44 migraine patients were included (90.9% female), with 80 attacks analyzed. Salivary CGRP levels rose at migraine onset. Significant interactions were found between DS and the linear (Est. [SE]: 19.4 [5.8], P=0.001) and quadratic terms of time (-19.1 [6.0], P=0.002). A significant three-way interaction with acute treated attack use was also detected (linear-term: -18.5 [6.2], P=0.005; quadratic-term: 19.2 [6.8], P=0.005). Molecular phenotyping revealed 72.7% (32/44) of patients had only CGRP-dependent attacks, and 27.3% (12/44) had non-CGRP-dependent migraine attacks. Patients with only CGRP-dependent attacks were linked to younger age, shorter disease duration, higher aura prevalence, and fewer monthly headache days (P<0.05). Erenumab treatment exploration did not alter CGRP levels during migraine attacks.
Investigators concluded that salivary CGRP levels fluctuate across migraine frequencies and may be associated with DS.
Source: thejournalofheadacheandpain.biomedcentral.com/articles/10.1186/s10194-024-01772-9
