No significant differences have been observed in cerebral γ-aminobutyric acid (GABA) levels between patients who experience migraine with aura compared with healthy controls, indicating that in those with relatively mild migraine with aura, GABA levels in the occipital and parietal lobes are normal except during the migraine attacks. A cross-sectional imaging study on the subject was conducted at Aarhus University Hospital, located in Aarhus, Denmark, at the Center for Functionally Integrative Neuroscience. Results of the analysis were published in The Journal of Headache and Pain.
Recognizing that recent studies have indicated that a disturbance in the inhibitory GABA is involved in triggering migraine with aura, the investigators of the current study sought to examine the cortical metabolite concentrations in patients experiencing migraine with aura, theorizing that occipital GABA levels are lower among patients with migraine with aura. They aimed to explore this using a novel magnetic resonance spectroscopy sequence.
Using spin echo full-intensity acquired localized spectroscopy on a Siemens 3 Tesla magnetic resonance scanner, occipital and parietal metabolite concentrations were obtained for 14 patients who were experiencing migraine with aura and 16 healthy matched controls. All of the scans were performed at the Center at least 7 days after a participant’s last migraine attack. All of the patients underwent scanning between September 2015 and June 2016.
Results of the study reported that no significant differences were detected in GABA/total creatinine levels either in the occipital cortex (P =.744) or in the somatosensory cortex (P =.305). Major limitations of the current study include the low number of participants, as well as the lack of precise phenotyping.
The investigators concluded that the results of this study demonstrate that cortical GABA levels are normal in patients who experience relatively few migraine attacks, with prior studies having shown that cortical GABA levels in individuals who experience frequent migraines are reduced. Additional research into the inhibitory system in patients who experience migraine attacks is warranted to help establish the underlying mechanisms. Future studies should also address whether low GABA levels in patients with severe migraine headache are the results of the migraine aura or, rather, are a consequence of migraine prophylactic therapy.
Reference
Stærmose TG, Knudsen MK, Kasch H, Blicher JU. Cortical GABA in migraine with aura -an ultrashort echo magnetic resonance spectroscopy study. J Headache Pain. 2019;20(1):110.