Evidence map›Paper›PMID 40663492›Full record

ArticleHeadache2026

Changes in brainstem habituation during onabotulinumtoxinA treatment in chronic migraine: A prospective case-control study.

Gerlinde Freimark, Sebastian Strauss, Lucas H Overeem, Mira P Fitzek, Kristin S Lange, Carolin L Höhne, Uwe Reuter, Robert Fleischmann, Bianca Raffaelli

Abstract read
In one paragraph

Article in Headache, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

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Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

9 authors.

Gerlinde FreimarkDepartment of Neurology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany.
Sebastian StraussDepartment of Neurology, University Medicine Greifswald, Greifswald, Germany.
Lucas H OvereemDepartment of Neurology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany.
Mira P FitzekDepartment of Neurology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany.
Kristin S LangeDepartment of Neurology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany.
Carolin L HöhneDepartment of Neurology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany.
Uwe ReuterDepartment of Neurology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany.
Robert FleischmannDepartment of Neurology, University Medicine Greifswald, Greifswald, Germany.
Bianca RaffaelliDepartment of Neurology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany.ORCID 0000-0001-9758-1494

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

OBJECTIVES/

backgroundChronic migraine is a debilitating neurological disorder characterized by central sensitization and impaired brainstem habituation. OnabotulinumtoxinA is an established prophylactic treatment for chronic migraine, yet its effects on central trigeminal sensory processing remain incompletely understood. The nociceptive blink reflex (nBR) is a well-established neurophysiological tool for assessing brainstem excitability and central sensory processing within the trigeminal system. This prospective case-control study investigated longitudinal changes in brainstem neurophysiology following onabotulinumtoxinA treatment using the nBR.

methodsBetween November 2022 and April 2024, we assessed nBR habituation in 27 patients with chronic migraine and compared them with 27 age- and sex-matched healthy controls. Measurements were performed at peak efficacy (1 month postinjection, Month 1+) and prior to reinjection (3 months postinjection, Month 3+). Habituation of the polysynaptic R2 response was analyzed as the primary outcome.

resultsAt Month 1+, R2 nBR habituation in patients was similar to that observed in healthy controls (4-s interstimulus interval, ipsilateral: β = 0.10, 95% confidence interval [CI] = -0.16 to 0.36, p = 0.457); however, by Month 3+, patients showed a significant impairment in R2 habituation compared to healthy controls (4-s interstimulus interval, ipsilateral: β = -0.29, 95% CI = -0.55 to -0.03, p = 0.029). Correlation analyses revealed that reduced habituation was associated with increased monthly migraine days (4-s interstimulus interval, contralateral: r = 0.41, 95% CI = 0.02 to 0.69, p = 0.039) and prolonged intervals since the last onabotulinumtoxinA treatment (4-s interstimulus interval, Month 3+, ipsilateral: r = 0.33, 95% CI = 0.06 to 0.55, p = 0.018), which aligns with the clinical observation of wearing off. Supporting this notion, patients with more prior treatment cycles exhibited sustained improvement in habituation deficits (4-s interstimulus interval, Month 3+, ipsilateral: r = -0.46, 95% CI = -0.71 to -0.09, p = 0.017). The monosynaptic R1 component remained unchanged between Month 1+ and 3+ (4-s interstimulus interval, ipsilateral: β = -0.028, 95% CI = -0.067 to 0.011, p = 0.164), emphasizing a specific treatment effect of trigeminal system-mediated pain processing at the brainstem level.

conclusionThese findings indicate that onabotulinumtoxinA exerts a neuromodulatory effect on brainstem neurophysiology, with R2 habituation improving during peak treatment efficacy and declining as the effect wears off. The results underscore the time-dependent central effects of onabotulinumtoxinA on nociceptive processing within the trigeminal system. Future research should investigate the nBR as a potential biomarker for optimizing onabotulinumtoxinA treatment strategies in chronic migraine.

Indexed as

Acetylcholine Release InhibitorsBlinkingBotulinum Toxins, Type ABrain StemHabituation, PsychophysiologicMigraine DisordersNeuromuscular AgentsAdultCase-Control StudiesChronic DiseaseFemaleHumansMaleMiddle AgedProspective StudiesAcetylcholine Release InhibitorsBotulinum Toxins, Type ANeuromuscular Agentsonabotulinum toxin Achronic migrainedisease modificationneurophysiologyonabotulinumtoxinA

Identifiers

PMID40663492
PMCPMC13044560

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