Objective
To demonstrate that calcitonin gene–related peptide (CGRP) induces headache exacerbation with migraine‐like features in patients with persistent post‐traumatic headache (PTH) attributed to ...mild traumatic brain injury (TBI).
Methods
A randomized, double‐blind, placebo‐controlled, two‐way crossover study was conducted. Analyses were intention‐to‐treat. Eligible patients were aged 18 to 65 years and had a history of persistent PTH after mild TBI for at least 12 months. Patients were randomized to receive an intravenous infusion of 1.5μg/min of CGRP or placebo (isotonic saline) over 20 minutes on two separate experimental days. A 12‐hour observational period was used to evaluate the following outcomes: (1) difference in incidence of headache exacerbation with migraine‐like features and (2) difference in area under the curve for headache intensity scores.
Results
Thirty patients (mean age = 37 years, 25 women 83%) were randomized and completed the study. During the 12‐hour observational period, 21 of 30 patients (70%) developed headache exacerbation with migraine‐like features after CGRP, compared with 6 patients (20%) after placebo (p < 0.001). The baseline‐corrected area under the curve for headache intensity scores was significantly larger after CGRP, compared with placebo (p < 0.001).
Interpretation
Patients with persistent PTH are hypersensitive to CGRP, which underscores its pathophysiological importance. Furthermore, CGRP‐targeted therapies might provide a novel mechanism‐based treatment option for patients with persistent PTH. ANN NEUROL 2020;88:1220–1228
To assess the prevalence or relative frequency of paroxysmal hemicrania and its clinical features in the adult general population and among adult patients evaluated for headache in tertiary care.
...Paroxysmal hemicrania is a rare trigeminal autonomic cephalalgia with characteristic attacks of headache, associated cranial autonomic symptoms and signs, and an absolute response to indomethacin. Its epidemiological burden remains unknown in both the adult general population and among adult patients evaluated for headache in a tertiary care setting. Moreover, the frequencies of the clinical features associated with paroxysmal hemicrania have not been well established.
A literature search of PubMed and Embase was conducted from January 1, 1988, to January 20, 2023. Eligible for inclusion were observational studies reporting the point prevalence or relative frequency of paroxysmal hemicrania or its clinical features in the adult general population or among adult patients evaluated for headache in tertiary care. Two independent investigators (M.J.H. and J.G.L.) performed the title, abstract, and full-text article screening. Each included study's risk of bias was critically appraised using the Joanna Briggs Institute Critical Appraisal Checklist for Studies Reporting Prevalence Data. Estimates of prevalence or relative frequency were calculated using a random-effects meta-analysis. The between-study heterogeneity was assessed using the I
statistic and further explored with meta-regression. This study was pre-registered on PROSPERO (identifier: CRD42023391127).
A total of 17 clinic-based studies and one population-based study met the eligibility criteria. Importantly, an overall high risk of bias was observed across the eligible studies. The relative frequency of paroxysmal hemicrania was estimated to be 0.3% (95% CI, 0.2%-0.5%) among adult patients evaluated for headache in tertiary care with considerable heterogeneity (I
= 76.4%). No cases with paroxysmal hemicrania were identified among 1,838 participants in a population-based sample. Moreover, the most prevalent cranial autonomic symptoms were lacrimation (77.3% 95% Cl, 62.7%-87.3%), conjunctival injection (75.0% 95% Cl, 60.3%-85.6%), and nasal congestion (47.7% 95% Cl, 33.6%-62.3%).
Our findings suggest that paroxysmal hemicrania is a rare disorder among adults evaluated for headache in tertiary care, while its prevalence in the general population remains unknown. Further studies focusing on the clinical features of paroxysmal hemicrania are warranted.
Pituitary adenylate cyclase-activating polypeptide-38 (PACAP-38), known for its role in migraine pathogenesis, has been identified as a novel drug target. Given the clinical parallels between ...post-traumatic headache (PTH) and migraine, we explored the possible role of PACAP-38 in the pathogenesis of PTH. To this end, we conducted a randomized, double-blind, placebo-controlled, two-way crossover trial involving adult participants diagnosed with persistent PTH resulting from mild traumatic brain injury. Participants were randomly assigned to receive a 20-min continuous intravenous infusion of either PACAP-38 (10 pmol/kg/min) or placebo (isotonic saline) on two separate experimental days, with a 1-week washout period in between. The primary outcome was the difference in incidence of migraine-like headache between PACAP-38 and placebo during a 12-h observational period post-infusion. The secondary outcome was the difference in the area under the curve (AUC) for baseline-corrected median headache intensity scores during the same 12-h observational period. Of 49 individuals assessed for eligibility, 21 were enrolled and completed the trial. The participants had a mean age of 35.2 years, and 16 (76%) were female. Most 19 of 21 (90%) had a migraine-like phenotype. During the 12-h observational period, 20 of 21 (95%) participants developed migraine-like headache after intravenous infusion of PACAP-38, compared with two (10%) participants after placebo (P < 0.001). Furthermore, the baseline-corrected AUC values for median headache intensity scores during the 12-h observational period was higher after PACAP-38 than placebo (P < 0.001). These compelling results demonstrate that PACAP-38 is potent inducer of migraine-like headache in people with persistent PTH. Thus, targeting PACAP-38 signalling might be a promising avenue for the treatment of PTH.
Background
Migraine is a multiphasic neurovascular disorder, where headache can be succeeded by postdromal symptoms. However, there are limited research on postdromal symptoms. This study aimed to ...investigate the proportion of individuals with migraine from a tertiary care unit reporting postdromal symptoms in adherence with the ICHD-3 definition. We also aimed to examine how the means of enquiry might influence the estimated proportions. Additionally, we explored whether any clinical features might affect the likelihood of reporting postdromal symptoms. Finally, we assessed to what extend the postdromal symptoms might impact the disease burden.
Methods
In a cross-sectional study, we enrolled adult participants diagnosed with migraine who were asked to report their postdromal symptoms (i.e., unprompted reporting). Subsequently, a 16-item list was used to further ascertain the occurrence of postdromal symptoms (i.e., prompted reporting). Clinical characteristics were obtained through a semi-structured interview. Moreover, electronic questionnaires were used to assess the disease burden, i.e., the Six-Item Headache Impact Test (HIT-6), Migraine Disability Assessment (MIDAS), and the World Health Organization Disability Assessment 2.0 (WHODAS 2.0).
Results
Among 631 participants with migraine, a higher proportion experienced at least one postdromal symptom when prompted (
n
= 509 80.7%) compared with unprompted reporting (
n
= 421 66.7%,
P
< 0.001). Furthermore, the total number of postdromal symptoms experienced was greater with prompted than unprompted reporting (medians 3 IQR 1 – 6 versus 1 IQR 0 – 2;
P
< 0.001). Furthermore, the likelihood of reporting postdromal symptoms increased with the presence of premonitory symptoms and decreased with higher number of monthly migraine days. Weak correlations were identified between the number of postdromal symptoms reported and both HIT-6 (
ρ
= 0.14;
P
< 0.001) and WHODAS scores (
ρ
= 0.15;
P
< 0.001), whilst no correlation was observed with MIDAS score (
ρ
= 0.08;
P
= 0.054).
Conclusions
Postdromal symptoms are prevalent in individuals with migraine from a tertiary care unit. However, reported estimates warrant cautious interpretation as they depend on the means of enquiry, presence of premonitory symptoms, and frequency of monthly migraine days. Moreover, a weak correlation was identified between the number of postdromal symptoms and both HIT-6 and WHODAS scores, indicating only a marginal influence on the disease burden.
Graphical Abstract
Structural imaging can offer insights into the cortical morphometry of migraine, which might reflect adaptations to recurring nociceptive messaging. This study compares cortical morphometry between a ...large sample of people with migraine and healthy controls, as well as across migraine subtypes.
Adult participants with migraine and age-matched and sex-matched healthy controls attended a single MRI session with magnetization-prepared rapid acquisition gradient echo and fluid-attenuated inversion recovery sequences at 3T. Cortical surface area, thickness, and volume were compared between participants with migraine (including subgroups) and healthy controls across the whole cortex within FreeSurfer and reported according to the Desikan-Killiany atlas. The analysis used cluster-determining thresholds of
< 0.0001 and cluster-wise thresholds of
< 0.05, adjusted for age, sex, and total intracranial volume.
A total of 296 participants with migraine (mean age 41.6 years ± 12.4 SD, 261 women) and 155 healthy controls (mean age 41.1 years ± 11.7 SD, 133 women) were included. Among the participants with migraine, 180 (63.5%) had chronic migraine, 103 (34.8%) had migraine with aura, and 88 (29.7%) experienced a migraine headache during the scan. The total cohort of participants with migraine had reduced cortical surface area in the left insula, compared with controls (
< 0.0001). Furthermore, participants with chronic migraine (n = 180) exhibited reduced surface area in the left insula (
< 0.0001) and increased surface area in the right caudal anterior cingulate cortex (
< 0.0001), compared with controls. We found no differences specific to participants with aura or ongoing migraine headache. Post hoc tests revealed a positive correlation between monthly headache days and surface area within the identified anterior cingulate cluster (
= 0.014).
The identified cortical changes in migraine were limited to specific pain processing regions, including the insula and caudal anterior cingulate gyrus, and were most notable in participants with chronic migraine. These findings suggest persistent cortical changes associated with migraine.
The REFORM study (clinicaltrials.gov identifier: NCT04674020).
Background
Although the involvement of calcitonin gene-related peptide (CGRP) in migraines is well-established, its specific role in investigating the aura phase, which often precedes the headache, ...remains largely unexplored. This study aims to instigate CGRP’s potential in triggering aura, thus establishing its role in the early stages of migraine.
Methods
In this open-label, non-randomized, single-arm trial, 34 participants with migraine with aura received continuous intravenous infusion of CGRP (1.5 µg/min) over 20 min on a single experimental day. Participants were required to be free of headache and report no use of acute medications 24 h before infusion start. The primary endpoint was the incidence of migraine aura during the 12-hour observational period after the start of infusion.
Results
Thirteen (38%) of 34 participants developed migraine aura after CGRP infusion. In addition, 24 (71%) of 34 participants developed migraine headache following CGRP infusion.
Conclusions
Our findings suggest that CGRP could play an important role in the early phases of a migraine attack, including during the aura phase. These insights offer a new perspective on the pathogenesis of migraines with aura. They underscore the need for additional research to further explore the role of CGRP in these initial stages of a migraine attack, and potentially inform future development of therapeutic interventions.
Trial registration
ClinicalTrials.gov Identifier: NCT04592952.
Graphical Abstract
Objective
To investigate whether levcromakalim (a KATP channel opener) induces migraine-like headache in people with persistent post-traumatic headache who had no known history of migraine.
Methods
...In a randomized, double-blind, placebo-controlled, 2-way crossover trial, participants were randomly assigned to receive a 20-minute continuous intravenous infusion of levcromakalim (50 µg/mL) or placebo (isotonic saline) on two separate experimental days with a 1-week wash-out period in between. The primary endpoint was the difference in incidence of migraine-like headache between levcromakalim and placebo during a 12-hour observational period after infusion start. The secondary endpoint was the difference in area under the curve for baseline-corrected median headache intensity scores between levcromakalim and placebo during the 12-hour observational period.
Results
A total of 21 participants with persistent post-traumatic headache were randomized and completed the trial. During the 12-hour observational period, 12 (57%) of 21 participants reported experiencing migraine-like headache following the levcromakalim infusion, compared with three after placebo (P = 0.013). Moreover, the baseline-corrected median headache intensity scores were higher following the levcromakalim infusion than after placebo (P = 0.003).
Conclusion
Our findings suggest that KATP channels play an important role in the pathogenesis of migraine-like headache in people with persistent post-traumatic headache. This implies that KATP channel blockers might represent a promising avenue for drug development. Further research is warranted to explore the potential therapeutic benefits of KATP channel blockers in managing post-traumatic headache.
Trial Registration: ClinicalTrials.gov Identifier: NCT05243953
Background
Large conductance calcium-activated potassium (BK
Ca
) channels have been implicated in the neurobiological underpinnings of migraine. Considering the clinical similarities between ...migraine and persistent post-traumatic headache (PPTH), we aimed to examine whether MaxiPost (a BK
Ca
channel opener) could induce migraine-like headache in persons with PPTH.
Methods
This is a randomized double-blind, placebo-controlled, two-way crossover study from September 2023 to December 2023. Eligible participants were adults with PPTH after mild traumatic brain injury who reported having no personal history of migraine. The randomized participants received a single dose of either MaxiPost (0.05 mg/min) or placebo (isotonic saline) that was infused intravenously over 20 minutes. The two experiment sessions were scheduled at least one week apart to avoid potential carryover effects. The primary endpoint was the induction of migraine-like headache after MaxiPost as compared to placebo within 12 hours of drug administration. The secondary endpoint was the area under the curve (AUC) values for headache intensity scores between MaxiPost and placebo over the same 12-hour observation period.
Results
Twenty-one adult participants (comprising 14 females and 7 males) with PPTH were enrolled and completed both experiment sessions. The proportion of participants who developed migraine-like headache was 11 (52%) of 21 participants after MaxiPost infusion, in contrast to four (19%) participants following placebo (
P
= .02). Furthermore, the median headache intensity scores, represented by AUC values, were higher following MaxiPost than after placebo (
P
< .001).
Conclusions
Our results indicate that BK
Ca
channel opening can elicit migraine-like headache in persons with PPTH. Thus, pharmacologic blockade of BK
Ca
channels might present a novel avenue for drug discovery. Additional investigations are nonetheless needed to confirm these insights and explore the therapeutic prospects of BK
Ca
channel blockers in managing PPTH.
ClinicalTrials.gov Identifier
NCT05378074.
Background
Estimates of proportions of people with migraine who report premonitory symptoms vary greatly among previous studies. Our aims were to establish the proportion of patients reporting ...premonitory symptoms and its dependency on the enquiry method. Additionally, we investigated the impact of premonitory symptoms on disease burden using Headache Impact Test (HIT-6), Migraine Disability Assessment (MIDAS) and World Health Organization Disability Assessment 2.0 (WHODAS 2.0), whilst investigating how various clinical factors influenced the likelihood of reporting premonitory symptoms.
Methods
In a cross-sectional study, premonitory symptoms were assessed among 632 patients with migraine. Unprompted enquiry was used first, followed by a list of 17 items (prompted). Additionally, we obtained clinical characteristics through a semi-structured interview.
Results
Prompted enquiry resulted in a greater proportion reporting premonitory symptoms than unprompted (69.9% vs. 43.0%; p < 0.001) and with higher symptom counts (medians 2, interquartile range = 0–6 vs. 1, interquartile range = 0–1; p < 0.001). The number of symptoms correlated weakly with HIT-6 (ρ = 0.14; p < 0.001) and WHODAS scores (ρ = 0.09; p = 0.041). Reporting postdromal symptoms or triggers increased the probability of reporting premonitory symptoms, whereas monthly migraine days decreased it.
Conclusions
The use of a standardized and optimized method for assessing premonitory symptoms is necessary to estimate their prevalence and to understand whether and how they contribute to disease burden.
Background
Phosphodiesterase 3 (PDE-3) inhibition have been implicated in the neurobiologic underpinnings of migraine. Considering the clinical similarities between migraine and persistent ...post-traumatic headache (PPTH), we aimed to ascertain whether PDE-3 inhibition can elicit migraine-like headache in persons with PPTH.
Methods
We tested cilostazol, which inhibits PDE-3, in a randomized, double-blind, placebo-controlled, two-way crossover study involving persons with PPTH attributed to mild traumatic brain injury. The randomized participants were allocated to receive oral administration of either 200-mg cilostazol or placebo (calcium tablet) on two separate experiment days. The primary end point was the incidence of migraine-like headache during a 12-hour observation window post-ingestion. The secondary endpoint was the area under the curve (AUC) for reported headache intensity scores during the same observation window.
Results
Twenty-one persons underwent randomization and completed both experiment days. The mean participants’ age was 41.4 years, and most (
n
= 17) were females. During the 12-hour observation window, 14 (67%) of 21 participants developed migraine-like headache post-cilostazol, in contrast to three (14%) participants after placebo (
P
=.003). The headache intensity scores were higher post-cilostazol than after placebo (
P
<.001).
Conclusions
Our results provide novel evidence showing that PDE-3 inhibition can elicit migraine-like headache in persons with PPTH. Given that PDE-3 inhibition increases intracellular cAMP levels, our findings allude to the potential therapeutic value of targeting cAMP-dependent signaling pathways in the management of PPTH. Further investigations are imperative to substantiate these insights and delineate the importance of cAMP-dependent signaling pathways in the neurobiologic mechanisms underlying PPTH.
ClinicalTrials.gov Identifier
NCT05595993.
