Chiara Abagnale (Italy)
Sapienza University of Rome, polo Pontino Department of Medico-Surgical Sciences and BiotechnologiesAuthor Of 2 Presentations
MONOCLONAL ANTIBODIES AGAINST THE CGRP RECEPTOR EXERT EFFECTS AT THE LEVEL OF THE CAUDAL TRIGEMINAL NUCLEUS AND ON THE SOMATOSENSORY CORTEX IN MIGRAINE PATIENTS
- Francesco Casillo (Italy)
Abstract
Background and Aims:
Erenumab is a monoclonal antibody against CGRP receptor approved as a prophylactic treatment of migraine. It is not yet clear if its neurophysiological effects are confined to the peripheral trigeminal system or also occur at the cortical level. This study assessed the neurophysiological effects of the drug in migrainous patients unresponsive to ≥2 prophylactic treatments.
Methods:
We prospectively enrolled 20 patients. For each patient we recorded the blink reflex (nBR), after stimulation of the right supraorbital nerve with a nociception specific concentric electrode, and the non-noxious somatosensory evoked potentials (SSEPs) after repetitive electrical stimulation of the median nerve. We measured nBR R2 area-under-the-curve (AUC) and habituation, and SSEP N20-P25 amplitude and habituation. Neurophysiological measurements were recorded before and at month-1 (T1) and month-2 (T2) before each monthly erenumab injection.
Results:
At T2, erenumab reduced the severity of headache, the mean monthly headache days and tablet intake (all p=<0.001). Compared to baseline, the nBR AUC was significantly reduced at T1. An increase in SSEP habituation, was noted at T1 and, more so, at T2 compared to the baseline (slope baseline =+0.103, T1 =-0.167, T2 =-0.229, p<0.05).
Conclusions:
The results of our study show that the clinical improvement induced by Erenumab can be attributed to neurophysiological changes occurring at both the brainstem and cortical levels.
IS THE MULTISENSORY INTEGRATION DIFFERENT BETWEEN MIGRAINE PATIENTS AND HEALTHY SUBJECTS? A STUDY OF CONCURRENT VISUAL AND SOMATOSENSORY STIMULATION
- Gabriele Sebastianelli (Italy)
Abstract
Background and Aims:
Merging of sensory information is an important process for all species. Both in humans and in animal models, co-application of bi-modal stimulations results in greater neural activation than the sum of each unimodal stimuli delivered independently. We have tested how the same process of multisensory integration take place in migraine patients, by evaluating the potential ability of concurrent visual and somatosensory stimulations to affect the mechanisms of habituation, an indirect hallmark of cortical responsivity.
Methods:
We recorded somatosensory evoked potentials (SSEPs) in twenty healthy volunteers and in twenty-one migraine patients before, during, and after simultaneous visual stimulation with a black-and-white checkerboard pattern-reversal. Six-hundred sweeps were acquired for each condition and partitioned off-line in 2 blocks of 100 sweeps for the calculation of habituation as the slope of the regression line between the 1st and the 2nd block of averaged N20-P25 SSEP amplitude response.
Results:
In both groups the visuo-somesthetic stimulation changed the SSEP N20-P25 habituation seen at baseline. In healthy subjects the concurrent stimulation provoked a loss of habituation (amplitude increment). In migraine patients, who had a deficient habituation at baseline, the simultaneous stimulation produced an amplitude decrement between 1st and 2nd block (habituation).
Conclusions:
There is ample scientific evidence which sustain that migraine patients have an atypical way of processing unimodal information. Our result suggests that also the multisensory integration is affected, and this process could influence the migraine cycle modifying habituation and cortical responsivity, which may lower the migraine threshold and might trigger an attack.