OBJECTIVE: The objective of this study was to describe and discuss patterns of migraine medication use in the entire Norwegian population.
METHODS: In this nationwide, observational study, all individuals with a migraine-related prescription between 2010 and 2020 were identified using the Norwegian Prescription Database. The outcomes of interest were the incidence and 1-year prevalence of migraine medication users, as well as individuals with triptan overuse. Patterns of medication use were statistically compared between women and men adjusted for age, year of treatment start, comorbidities and county of residence calculating adjusted odds ratios (aOR) with 95% confidence intervals (CI).
RESULTS: We identified 327,904 migraine medication users. The incidence ranged from 0.39% to 0.46%, and the 1-year prevalence increased from 1.99% to 2.99%. Preventive use increased >50% during the study period. Preventives were significantly more often prescribed to women than to men (39.72% vs. 33.75%; aOR 1.41, 95% CI 1.38 to 1.44). Triptan overuse was significantly more common among women, but women with overuse were more often using preventives, as compared to men (56.64% vs 52.69%; aOR = 1.43, 95% CI 1.37 to 1.49).
CONCLUSIONS: The prevalence of medically treated migraine is low. Overuse of triptans is frequent, especially among women. Clinicians should be encouraged to try out different triptans, recognize triptan overuse, and prescribe preventives when indicated.

OBJECTIVE: To qualitatively and quantitatively summarize the evidence for the use of onabotulinumtoxinA injections in children and adolescents with migraine.
BACKGROUND: There are limited evidence-based treatment options for youth with migraine, especially youth with chronic migraine (CM). OnabotulinumtoxinA injections are an established evidence-based treatment for adults with CM. While several studies have assessed their safety and efficacy among adolescents with CM, there are no published systematic reviews summarizing the pediatric evidence.
METHODS: We carried out a systematic review, reported according to the Preferred Reporting Items for Systematic Review and Meta-Analysis, aiming to identify studies that included five or more children and adolescents aged ≤18 years with a diagnosis of migraine, who were treated with ≥50 units (U) of onabotulinumtoxinA and had outcomes assessed ≥4 weeks after one or more injection cycle. Both observational studies and randomized controlled trials (RCTs) were eligible for inclusion. Two investigators independently carried out the first (titles and abstracts) and second (full text) screening stages, as well as data extraction and quality appraisal. The American Academy of Neurology risk of bias grading scheme was used to assess study risk of bias. Studies with adequate data were pooled using random effects meta-analyses, and Hedge\'s g standardized mean differences with 95% confidence intervals (CIs) were generated to estimate the effect sizes of the continuous outcomes included. Studies lacking data required for meta-analysis were summarized qualitatively.
RESULTS: We screened 634 studies and included 14 studies comprising 491 participants, of whom 489 had CM. Two studies were RCTs, 12 were observational uncontrolled studies, and all but one study included only youth with CM. Five Class IV observational uncontrolled studies were amenable to pooling in meta-analyses. After a mean of 2-2.6 injection cycles, headache frequency was shown to decrease significantly after treatment with onabotulinumtoxinA (Hedge\'s g = 0.97, 95% CI 0.58-1.35; p < 0.0001), as did severity (Hedge\'s g = 1.24, 95% CI 0.55-1.94; p = 0.0005), with both estimates having a large effect size magnitude. A Class I parallel-group RCT of one injection series (155 U, 74 U, or placebo), powered to detect a change in 4 headache days per month, did not find outcome differences between the active and placebo treatment arms. A Class IV crossover RCT showed superiority of active (155 U) versus placebo injections. The remaining Class IV observational studies that were excluded from the meta-analyses all showed improved outcomes with onabotulinumtoxinA injections over time. No serious adverse events related to treatment occurred.
CONCLUSIONS: OnabotulinumtoxinA injections have established safety for use in children and adolescents with CM and are likely effective in reducing headache frequency and severity over time. However, in the absence of an adequately powered parallel-group RCT assessing the efficacy of multiple injection cycles, it remains unclear if this intervention is superior to placebo.

OBJECTIVE: To confirm a previously reported association of TRPV1 rs8065080 with the risk of transformation from episodic (EM) to chronic migraine (CM) and to extend knowledge about the role of other TRPV1 single nucleotide polymorphisms (SNPs), we first investigated the impact of three TRPV1 SNPs (rs8065080, rs222747 and rs222749) on the risk of migraine chronification in a case-control study. A systematic review and meta-analysis were then conducted to summarize the accumulated findings.
METHODS: Genotyping of the selected TRPV1 SNPs was performed using TaqMan real-time PCR in 167 EM and 182 CM participants. Crude and adjusted odds ratios with associated 95% confidence intervals were calculated in the log-additive, dominant, and recessive genetic models. A comprehensive literature search was performed in PubMed, Web of Knowledge, Cochrane Library, and OpenGrey until February 2024.
RESULTS: In our case-control study, no association was found between TRPV1 SNPs and the risk of migraine chronification, both in the unadjusted logistic regression models and after adjustment for confounding clinical variables. The results of the meta-analysis with a total of 241 participants with EM and 223 with CM confirmed no association between TRPV1 SNPs and the risk of migraine chronification in any of the genetic models tested.
CONCLUSIONS: The results of the present case-control study and meta-analysis exclude a major role of TRPV1 rs8065080, rs222747, and rs222749 as risk factors for migraine chronification. However, further research is needed to investigate the gene-gene and gene-environment interactions of TRPV1 SNPs on the risk of transformation from episodic to chronic migraine.

Exosomes have been identified as optimal biomarkers to screen for multiple diseases. However, few studies focus on the abundant exosome population isolated from plasma of migraine. This study investigated whether proteins in abundant exosomes can aid in the diagnosis of chronic migraine (CM). Plasma exosomes were collected by centrifugation, from which protein samples were extracted. A pilot study (CM, 18; episodic migraine (EM), 26) followed by a second dataset (CM, 26; EM, 16; tension-type headache (TTH), 20; control, 22) was applied to establish a diagnostic model of CM. We employed proteomics based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) to search for potential candidate biomarkers in plasma exosomes from CM patients. In total, 530 proteins in plasma exosomes were co-detected. Among them, 13 proteins were found significantly dysregulated between the plasma exosomes of CM patients and other groups. The receiver operating characteristic curve analysis revealed a combination of six proteins (upregulated: RAP2B, AK1, BID, DAG1, PICALM, PSMB2) could distinguish CM patients with high accuracy. Linear correlation analysis showed that the combination was significantly correlated with Headache Impact Test (HIT-6) scores (assessing the negative impact of headaches on normal daily activity). The RT-qPCR results showed the same trends in CM models with nitroglycerin as the exosomal protein sequencing results. These data revealed dysregulated proteins in plasma exosomes of CM, and the combination of plasma exosomal proteins RAP2B, AK1, BID, DAG1, PICALM, and PSMB2 could serve as a novel candidate biomarker for CM diagnosis.

OnabotulinumtoxinA (BT-A) is used in different medical fields for its beneficial effects. BT-A, a toxin originally produced by the bacterium Clostridium botulinum, is widely known for its ability to temporarily paralyze muscles by blocking the release of acetylcholine, a neurotransmitter involved in muscle contraction. The literature continually reports new hypotheses regarding potential applications that do not consider blockade of acetylcholine release at the neuromuscular junction as a common pathway. In this opinion article, it is our aim to investigate the different pathway targets of BT-A in different medical applications. First of all, the acetylcholine effect of BT-A is used to reduce wrinkles for cosmetic purposes, in the treatment of urological problems, excessive sweating, temporomandibular joint disorders, obesity, migraine, spasticity in neurological diseases, and in various cases of muscle overactivity such as cervical dystonia, blepharospasm, and essential head tremor. In another potential pathway, glutamate A, CGRP, and substance P are targeted for pain inhibition with BT-A application in conditions such as migraine, trigeminal neuralgia, neuropathic pain, and myofascial pain syndrome. On the other hand, as a mechanism different from acetylcholine and pain mediators, BT-A is used in the treatment of hair loss by increasing oxygenation and targeting transforming growth factor-beta 1 cells. In addition, the effect of BT-A on the apoptosis of cancer cells is also known and is being developed. The benefits of BT-A applied in different doses to different regions for different medical purposes are shown in literature studies, and it is also emphasized in those studies that repeating the applications increases the benefits in the long term. The use of BT-A continues to expand as researchers discover new potential therapeutic uses for this versatile toxin.

Migraine is a leading cause of disability worldwide, yet it remains underrecognized and undertreated, especially in the pediatric and adolescent population. Chronic migraine occurs approximately in 1% of children and adolescents requiring preventive treatment. Topiramate is the only FDA-approved preventative treatment for children older than 12 years of age, but there is conflicting evidence regarding its efficacy. OnabotulinumtoxinA is a known and approved treatment for the management of chronic migraine in people older than 18 years. Several studies examine its role in the pediatric population with positive results; however, the clear-cut benefit is still unclear. OnabotulinumtoxinA seems not only to improve disability scores (PedMIDAS) but also to improve the quality, characteristics, and frequency of migraines in the said population. This systematic review aims to summarize the evidence on the efficacy, dosing, administration, long-term outcomes, and safety of onabotulinumtoxinA in pediatric and adolescent migraine. Eighteen studies met the eligibility criteria and were included in this review. The mean monthly migraine days (MMDs), decreased from of 21.2 days per month to 10.7 after treatment. The reported treatment-related adverse effects were mild and primarily injection site related and ranged from 0% to 47.0%. Thus, this review provides compelling evidence suggesting that OnabotulinumtoxinA may represent a safe and effective preventive treatment option for pediatric migraine.

To explore the mechanism of the classic formula Sanpian Decoction in treating chronic migraine, this study employed the four-dimensional data-dependent acquisition(4D-DIA) proteomics to analyze the effect of the decoction on chronic migraine in rats and experimentally verified the key differentially expressed proteins. Firstly, SD male rats were randomly divided into groups and repeatedly injected with nitroglycerin to prepare a chronic migraine model. After 7 consecutive days of gavage, rat grimace scale(RGS) was employed to evaluate the treatment efficacy. The trigeminal ganglion was collected for 4D-DIA proteomics, on the basis of which the diffe-rentially expressed proteins between groups were screened. Multiple databases were used for the Gene Ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) enrichment of the differentially expressed proteins. STRING and Cytoscape were employed to establish the protein-protein interaction(PPI) network. Western blot was employed to determine the expression level of the key diffe-rentially expressed protein TRPV1. The results showed that there were 517 differentially expressed proteins between blank group and model group and 221 differentially expressed proteins between model group and medium-dose Sanpian Decoction group. The GO and KEGG enrichment results showed that these differentially expressed proteins were mainly related to inflammatory response, injurious sensory stimulation, triglyceride metabolism, immune regulation, etc., which mainly involved the inflammation-related TRP, AMPK, PI3K-Akt, and TGF-β signaling pathways. The PPI network showed that the target proteins such as IGF, TOP2A, APOA1, CDK1, TTN, RYR1, and CSRP3 had high degrees. Compared with that in model group, the expression level of TRPV1 altered in medium-and high-dose Sanpian Decoction group(P<0.05). In conclusion, Sanpian Decoction may treat chronic migraine by regulating the inflammation-related pathways such as TRP, AMPK, and PI3K-Akt. It plays an important role in the regulation of TRPV1 protein and potentially modulates the perception of injurious stimuli, lipid metabolism, and immune responses.

OBJECTIVE: The objectives of this real-life study were to analyze the reversion of chronic migraine (CM) to episodic migraine (EM) with fremanezumab, evaluate its benefit on the symptomatology, and determine the influence of possible clinical features on the reversion.
BACKGROUND: The clinical manifestations of CM have a high impact on the quality of life of patients, and monoclonal antibodies such as fremanezumab are used as prophylactic treatment.
METHODS: Diagnosed CM patients treated for at least 3 months with monthly fremanezumab were interviewed. The data to assess efficacy were before treatment and at the time of the interview: monthly headache days (MHDs), daily headache hours (DHHs), monthly symptomatic medication days (MSMDs), percentage of patients with symptomatic medication overuse (SMO), and pain intensity with the numerical rating scale (NRS) score. Possible predictors of reversion were analyzed: percentage of patients treated for at least 12 months, hypertension, diabetes mellitus, depression, anxiety, symptomatic control with non-steroidal anti-inflammatory drugs (NSAIDs), triptans or both, and amitriptyline prophylaxis.
RESULTS: A total of 54 patients were included, of whom 40 (74.1%) were converters to EM. There were significant improvements in converters compared to pre-treatment in MHDs (28.0 vs. 5.0 days), as well as on the variables DHHs, MSMDs, and SMO. The percentage of erenumab failures was significantly higher in non-converters than in converters, as was the percentage of patients with anxiety.
CONCLUSIONS: High reversion from CM to EM was achieved with fremanezumab and notable symptomatological improvement, establishing previous failure to erenumab and anxiety as possible detrimental factors for reversion.

OBJECTIVE: We assessed whether the effectiveness of monoclonal antibodies (mAbs) targeting the calcitonin gene-related peptide (CGRP) pathway changes according to the duration of chronic migraine (CM) over 12 months.
BACKGROUND: In most patients, CM is a progressive disease starting with episodic migraine. Longer CM duration might be associated with more difficult treatment, probably because the mechanisms underlying chronicization are strengthened. Therefore, early treatment of CM could lead to better outcomes compared with later treatment.
METHODS: This cohort study included individuals with CM treated with anti-CGRP mAbs in two tertiary headache centers from April 2019 to May 2023. The primary outcome included a change in monthly migraine days (MMDs) from baseline to the third trimester of treatment, 10-12 months. Secondary outcomes established whether response to anti-CGRP mAbs has a more rapid onset in individuals with shorter CM duration compared with longer duration; they included change in MMDs, monthly headache days (MHDs), and days and number of intakes of acute medication during each trimester compared to baseline. Additional outcomes included persisting MMDs, MHDs, and days and number of intakes of acute medication during each trimester of treatment. Patients were compared across tertiles of the overall CM duration.
RESULTS: The study included 335 individuals with CM, with a median (interquartile range [IQR]) age of 48 (39-57) years; 270 (80.6%) were women. Patients in the highest tertile of CM duration (aged 18-60 years) were older than patients in the lower duration tertiles (0-7 years and 8-18 years, respectively), with a median (IQR) age of 56 (48-64) years compared with 42 (31-50) years, and 48 (39-56)years, respectively (p = 0.025); however, this difference was likely due to a correlation between age and disease duration. The change in MMDs from baseline to the last trimester of treatment (10-12 months) was comparable across tertiles of CM duration (median [IQR] -12 [-18 to -5] days, -12 [-17 to -6] days, and -12 [-18 to -4] days; p = 0.946). No difference emerged in secondary outcomes, suggesting a similar time to onset of anti-CGRP mAbs effect across all tertiles of CM duration.
CONCLUSIONS: Our data showed that anti-CGRP mAbs are effective and have a rapid onset of action in CM regardless of disease duration.

Background: MOH (medication overuse headache) is regarded as a complication of chronic migraines (CMs), with a general acknowledgment of reciprocal triggering between these two conditions. The present study aims to investigate the clinical parameters of relevance for the development of MOH among patients with CM, as well as for the subtype classification of MOHs. Method: We compared two groups of CM patients, with and without MOH, separated based on their demographic data and migraine characteristics. A subgroup of MOH accompanied by psychiatric co-morbidities (depression, anxiety, sleep disorder) was delineated, and the clinical features of relevance for the progression of MOH into the complicated state were evaluated. Results: The study revealed a higher prevalence of a family history of migraine in both the MOH and potentially complicated MOH subgroups (p < 0.001, p = 0.036), along with a higher prevalence of bilateral pain localization (p = 0.033, 0.021). Symptoms commonly associated with migraines, such as nausea, vomiting, photophobia, phonophobia, and osmophobia, were more common in both the MOH and potentially complicated MOH subgroups (p < 0.05). Furthermore, a positive correlation was found for the frequency (p < 0.001) and severity (p = 0.010) of migraine attacks and the duration of headaches (p = 0.007), atopy (p = 0.017), sleep disturbances (p = 0.011), and emotional stress (p = 0.022) in the MOH group. Conclusion: We found a positive correlation between the prevalence of MOH among patients with CM and a family history of migraines, higher frequency and intensity of headaches, bilateral manifestation, sleep disturbances, and emotional stress. Moreover, symptoms accompanying migraines were found to be more prevalent in individuals with MOH and potentially complicated MOH.