What the Gut Can Teach Us About Migraine. Curr Pain Headache Rep. 2015;19:33. [PMID: 26049770 DOI: 10.1007/s11916-015-0501-4]

The association between carbohydrate quality index and headache severity, disability and duration among women with migraine a cross-sectional study

BACKGROUND & AIM

This study aimed to examine the association between Carbohydrate Quality Index (CQI) and headache severity, disability and duration among women with migraine.

MATERIALS & METHODS

In this cross-sectional study, 266 women (aged 18-45 years) were enrolled using a 147-item food frequency questionnaire (FFQ). CQI was defined by four criteria: fiber intake, dietary glycemic index (DGI), whole grains/total grains ratio and solid carbohydrates/total carbohydrates ratio. Anthropometric measurements, visual analogue scale (VAS), migraine disability assessment (MIDAS), and headache duration were assessed for all participants.

RESULTS

Participants with a high adherence to CQI had lower odds of moderate pain (OR = 0.45; 95% CI = 0.21-0.94; P = 0.03) and severe pain (OR = 0.39; 95% CI = 0.18-0.82; P = 0.01) compared to those with a low adherence to CQI. After controlling for potential confounders, individuals with the greatest adherence to CQI showed a 78% reduced prevalence in severe pains and a 63% decreased occurrence in moderate pains compared to those with the lowest adherence (OR = 0.22; 95% CI = 0.09-0.55; P = 0.01 and OR = 0.37; 95% CI = 0.16-0.84; P = 0.01, respectively). Moreover, Subjects with higher adherence to CQI had lower odds of headache duration (OR = 0.54; 95% CI= 0.31-0.96; P = 0.03). The significant association remained (P < 0.05) even after confounding variables (OR = 0.59; 95 % CI = 0.35-1.002; P = 0.05). Despite adjusting for confounding valuables, there was no significant association between the CQI and MIDAS scores (P > 0.05).

CONCLUSION

Higher adherence to CQI was associated with lower severity and duration in patients with migraine. Further studies are needed to confirm these results.

Migraine is associated with the development of adult patients with inflammatory bowel disease: a nationwide, population-based study

It has been reported that migraine is more common in patients with inflammatory bowel disease (IBD) than in general. However, the impact of migraine on the development of IBD has not yet been elucidated. The aim of this study was to determine the association between migraine and the development of IBD. This nationwide population-based cohort study was conducted using the Korean National Health Insurance Service (NHIS) database. A total of 10,628,070 people aged 20 years or older who had undergone a national health examination conducted by the NHIS in 2009 were followed up until 2017. The study population was divided into two groups according to the presence or absence of migraine. We analyzed the incidence of newly developed IBD, Crohn's disease (CD), or ulcerative colitis (UC) during the follow-up period. The incidence of IBD was significantly higher in patients with migraine (adjusted hazard ratio [aHR] with 95% confidence interval [95%CI] of 1.31 [1.173-1.468], p < 0.001), CD (aHR with 95%CI of 1.58 [1.237-2.013], p < 0.001) and UC (aHR with 95%CI of 1.26 [1.106-1.424], p < 0.001) than in those without migraine. After 5 years of follow-up, those with migraine showed curves implying cumulative incidences of IBD with a steep increase, especially for CD. In subgroup analysis, migraine was associated with the risk of UC in males (aHR, 1.431 vs. 1.117; interaction p = 0.042). Migraine is significantly associated with the development of IBD. Patients with migraine should be monitored carefully for the development of IBD.

[A comparative assessment of microbiocenosis of saliva and oropharynx in patients with migraine]

OBJECTIVE

To identify changes in the microbiome of saliva and to compare it with the microbiome of the oropharynx of patients with migraine.

MATERIAL AND METHODS

Sixty patients with migraine (21-56 years old), were examined using a headache diary, MIDAS and VAS. A microbiological examination of saliva and smear from the mucosa of the posterior wall of the oropharynx with evaluation by the method of mass spectrometry of microbial markers (MSMM) with the determination of 57 microorganisms was performed. All patients had comorbid chronic diseases of the gastrointestinal tract and upper respiratory tract (URT), according to anamnestic data and examination by specialists.

RESULTS

A significant increase in the content of markers of resident (conditionally pathogenic) microorganisms characteristic of chronic diseases of URT (strepto- and staphylococci); markers of transient microorganisms characteristic of intestinal microflora (clostridia, gram-negative rods, anaerobes) that are normally absent; viral markers of cytomegaloviruses and herpes groups; a decrease in the content of fungi were identified in saliva. A comparative analysis of the microbiome of saliva and oropharynx showed: 1) a significant decrease in the concentration of coccal flora Enterococcus spp., Streptococcus mutans, Staphylococcus aureus, anaerobic bacteria Clostridium difficile and Clostridium perfringens in saliva; enterobacteria Helicobacter pylori; gram-negative rods Kingella spp., fungi and Epstein-Barr virus; 2) an increase in salivary concentrations of Staphylococcus epidermidis, anaerobic Clostridium ramosum and Fusobacterium spp./Haemophilus spp. and gram-negative bacilli Porphyromonas spp.

CONCLUSION

A comparative assessment of the microbiota of a smear from the posterior wall of the oropharynx and saliva using MMSM showed the presence of dysbiosis both in the oropharynx and in the saliva of patients with migraine. However, there were fewer deviations from the norm in saliva, therefore, for diagnostic purposes, a smear from the posterior wall of the oropharynx is more significant as a biomarker for patients with migraine.

Association Between Migraine and Gastrointestinal Disease in Pediatric Patients: A Propensity Score Weighting Approach

Purpose

Migraine is a neurological disorder affecting pediatric patients of all age groups, with a prevalence ranging from approximately 5% to 15%. It significantly impacts the quality of life in children and adolescents, potentially hampering their learning abilities, school performance, and daily activities. This study investigated the association between migraine and several prevalent gastrointestinal (GI) diseases in pediatric patients.

Patients and Methods

We analyzed the Health Insurance Review and Assessment Service Pediatric Patient Sample (HIRA-PPS) dataset from South Korea. Propensity scores based on patient characteristics (age, sex, and insurance type) were employed through the inverse probability of treatment weighting (IPTW) in binary logistic regression. We included gastroesophageal disease (GERD), peptic ulcer disease (PUD), gastritis, dyspepsia, irritable bowel syndrome (IBS), and inflammatory bowel disease (IBD) as GI diseases.

Results

A total of 683,347 patients from the HIRA dataset were included in the study. After IPTW adjustment, the prevalence of GI diseases among pediatric patients with migraine remained significantly increased (OR 4.15; 95% CI 4.12-4.18). Migraine patients showed higher prevalence rates for all six individual GI diseases, with GERD (OR 4.11; 95% CI 4.05-4.16) and IBS (OR 3.79; 95% CI 3.74-3.84) showing the highest associations. We also confirmed a progressively increasing association between the presence of diagnosed migraine and GI diseases.

Conclusion

This study highlights a strong association between pediatric migraine and GI diseases, even after adjusting for patient characteristics. The elevated prevalence of various GI diseases in migraine patients suggests the need for comprehensive approaches to their prevention and treatment.

The Gut-brain Connection and Episodic Migraine: an Update

PURPOSE OF REVIEW

Historical evidence suggests a shared underlying etiology for migraine and gastrointestinal (GI) disorders that involves the gut-brain axis. Here we provide narrative review of recent literature on the gut-brain connection and migraine to emphasize the importance of tailoring treatment plans for patients with episodic migraine who experience GI comorbidities and symptoms.

RECENT FINDINGS

Recent population-based studies report the prevalence of migraine and GI disorders as comorbidities as well as overlapping symptomology. American Headache Society (AHS) guidelines have integrated GI symptoms as part of migraine diagnostic criteria and recommend nonoral therapies for patients with GI symptoms or conditions. Nasal delivery is a recommended nonoral alternative; however, it is important to understand potential adverse events that may cause or worsen GI symptoms in some patients due to the site of drug deposition within the nasal cavity with some nasal therapies. Lastly, clinical perspectives emphasize the importance of identifying GI symptoms and comorbidities in patients with episodic migraine to best individualize migraine management. Support for an association between the gut-brain axis and migraine continues to prevail in recent literature; however, the relationship remains complex and not well elucidated. The presence of GI comorbidities and symptoms must be carefully considered when making treatment decisions for patients with episodic migraine.

Migraine as a Disease Associated with Dysbiosis and Possible Therapy with Fecal Microbiota Transplantation

Migraine is a painful neurological condition characterized by severe pain on one or both sides of the head. It may be linked to changes in the gut microbiota, which are influenced by antibiotic use and other factors. Dysbiosis, which develops and persists as a result of earlier antibiotic therapy, changes the composition of the intestinal flora, and can lead to the development of various diseases such as metabolic disorders, obesity, hematological malignancies, neurological or behavioral disorders, and migraine. Metabolites produced by the gut microbiome have been shown to influence the gut-brain axis. The use of probiotics as a dietary supplement may reduce the number and severity of migraine episodes. Dietary strategies can affect the course of migraines and are a valuable tool for improving migraine management. With fecal microbiota transplantation, gut microbial restoration is more effective and more durable. Changes after fecal microbiota transplantation were studied in detail, and many data help us to interpret the successful interventions. The microbiological alteration of the gut microflora can lead to normalization of the inflammatory mediators, the serotonin pathway, and influence the frequency and intensity of migraine pain.

A causal effects of gut microbiota in the development of migraine

BACKGROUND

The causal association between the gut microbiome and the development of migraine and its subtypes remains unclear.

METHODS

The single nucleotide polymorphisms concerning gut microbiome were retrieved from the gene-wide association study (GWAS) of the MiBioGen consortium. The summary statistics datasets of migraine, migraine with aura (MA), and migraine without aura (MO) were obtained from the GWAS meta-analysis of the International Headache Genetics Consortium (IHGC) and FinnGen consortium. Inverse variance weighting (IVW) was used as the primary method, complemented by sensitivity analyses for pleiotropy and increasing robustness.

RESULTS

In IHGC datasets, ten, five, and nine bacterial taxa were found to have a causal association with migraine, MA, and MO, respectively, (IVW, all P < 0.05). Genus.Coprococcus3 and genus.Anaerotruncus were validated in FinnGen datasets. Nine, twelve, and seven bacterial entities were identified for migraine, MA, and MO, respectively. The causal association still exists in family.Bifidobacteriaceae and order.Bifidobacteriales for migraine and MO after FDR correction. The heterogeneity and pleiotropy analyses confirmed the robustness of IVW results.

CONCLUSION

Our study demonstrates that gut microbiomes may exert causal effects on migraine, MA, and MO. We provide novel evidence for the dysfunction of the gut-brain axis on migraine. Future study is required to verify the relationship between gut microbiome and the risk of migraine and its subtypes and illustrate the underlying mechanism between them.

Associations between the Gut Microbiome and Migraines in Children Aged 7-18 Years: An Analysis of the American Gut Project Cohort

BACKGROUND

The gut microbiome seems to play a role in migraines through increasing intestinal epithelial permeability and pro-inflammatory processes. The associations between the gut microbiome and migraines are uncertain in children.

AIM

The purpose of this quantitative study was to examine the associations between the gut microbiome and migraines in children aged 7-18 years from the American Gut Project (AGP).

METHOD

A cohort of children aged 7-18 years from the AGP was analyzed. 16S rRNA V4 gene sequences for the gut microbiome, migraines, and demographics were obtained from the AGP Public Repository. After quality control of 16S rRNA gene sequences, α-diversity (Shannon, Faith's_PD, and evenness) and β-diversity metrics (Bray-Curtis and weighted-UniFrac distances), taxonomy, and abundance analyses were implemented using QIIME 2.

RESULTS

In total, 381 children (341 without migraines; 40 with professional or self-diagnosed migraines) were analyzed with a mean age of 11.5 years. Compared with those without migraines, children with migraines showed lower estimates in Shannon and Faith's_PD (p < .01). Both Bray-Curtis and weighted-UniFrac distances displayed the gut microbial dissimilarities between these two groups (p = .001). Children with migraines had higher abundances in genus of phylum Bacteroidetes (Bacteroides, Parabacteroides, Odoribacter), Actinobacteria (Eggerthella, Varibaculum), Firmicutes (SMB53, Lachnospira, Dorea, Veillonella, Anaerotruncus, Butyricicoccus, Coprobacillus, Eubacterium), and Proteobacteria (Sutterella) than children without migraines.

CONCLUSIONS

Associations of the gut microbiome diversity and abundances with migraines in children indicated potential biological mechanisms of migraines. Future work needs to confirm our findings in children.

Migraine and obesity: what is the real direction of their association?

INTRODUCTION

In recent decades, studies have addressed the issue of how migraine and obesity are related and have suggested obesity as a risk factor for migraine headache. However, the exact direction of this relationship remains under debate. In this review, the authors summarize the evidence that have suggested migraine as a risk factor for obesity and overweightness.

AREAS COVERED

This article reviews the results of the previous research published on PubMed and Scopus databases (from 2000 to 2020) concerning the association between migraine and obesity to determine the actual direction of their association. Special attention has been given to the common mechanistic pathways involved in the pathophysiology of migraine and obesity.

EXPERT OPINION

The majority of research conducted thus far has considered obesity as a risk factor for migraine. However, because of the cross-sectional design of available research, we cannot be certain of the proposed direction of this association. There is evidence supporting the hypothesis that obesity can serve as a consequence of migraine through the effects of neuropeptides, inflammatory mediators, adipokines, gut microbiota and modifications in eating behavior and lifestyle. However, the real direction of the relationship between migraine and obesity should be further investigated in large prospective studies.

Evaluation of a Polyherbal Formulation on the Management of Migraine Headaches due to Functional Dyspepsia: A Double-Blind, Randomized, Placebo-Controlled Clinical Trial

A holistic concept based on traditional Persian medicine (TPM) describes a headache with a gastrointestinal (GI) origin (gastric-headache). Although the neurological manifestations of this headache are similar to those of other headaches, its etiology is different. Considering its simultaneous effects on the brain and GI system, a formulation was designed based on this concept. This study aimed to determine the safety and efficacy of the designed formulation on migraine headache (MH) associated with functional dyspepsia (FD). A total of 75 diagnosed cases of MH patients with concurrent FD were randomly divided equally into 3 groups: (i) the polyherbal formulation, sodium valproate (VPA), and amitriptyline group, (ii) VPA, amitriptyline, and polyherbal formulation placebo group, and (iii) the polyherbal formulation and VPA placebo group. The primary outcomes, including frequency, duration, and severity of MH attacks, were measured at baseline and weeks 4, 8, and 12. However, secondary outcomes, including the Headache Impact Test 6 (HIT-6) Questionnaire and Parkman's score, were evaluated at baseline and end of treatment. The frequency, duration, and severity of migraine (P < 0.001 for all cases), HIT-6 (P < 0.001 for all cases), and FD (P < 0.001 for all cases) scores at the end of treatment showed a significant decrease in the 3 groups compared to the baseline. However, the differences in those variables between the 3 groups were not significant at the end of the study. The polyherbal formulation alone may improve the symptoms of migraine patients and other groups. This effect could be due to improving digestion and FD in migraine patients.

Dysbiosis and Migraine Headaches in Adults With Celiac Disease

One of the most significant illnesses associated with gluten is celiac disease, which encompasses many conditions. It is generally recognized that neurological manifestations can occur either at the time of the disease onset or as the illness continues to develop. One of the main clinical presentations of celiac disease is headache, either in the form of migraine or in an unspecific form. Migraine pathophysiology is intricate and still poorly understood. Several mechanisms involving the gut-brain axis have been proposed to explain this association. These include the interaction of chronic inflammation with inflammatory and vasoactive mediators, the modulation of the intestinal immune environment of the microbiota, and the dysfunction of the autonomic nervous system. However, further research is required to fully comprehend the fundamental mechanisms and pathways at play. This review aims to give a narrative summary of the literature on celiac disease's neurological symptoms, particularly migraines, and to assess any potential associations to dysbiosis, an imbalance in the microbiome.

The Pathogenetic Role of Melatonin in Migraine and Its Theoretic Implications for Pharmacotherapy: A Brief Overview of the Research

Migraine is a chronic disease of global concern, regardless of socio-economic and cultural background. It most often and intensely affects young adults, especially women. Numerous mechanisms of a migraine attack have been identified (disturbances in the reaction of vessels, functions of neurotransmitters, cortical neurons, ion channels, receptors, the process of neurogenic inflammation), and many of its symptoms can be explained by activation of the hypothalamus and disturbances in its communication with other brain regions (including the brainstem). Numerous neuropeptides and neurochemical systems also play a role in migraine. One of them is melatonin, a hormone that allows the body to adapt to cyclically changing environmental and food conditions. In this article, we present the pathophysiological basis of melatonin release from the pineal gland and other tissues (including the intestines) under the influence of various stimuli (including light and food), and its role in stimulating the brain structures responsible for triggering a migraine attack. We analyze publications concerning research on the role of melatonin in various headaches, in various stages of migraine, and in various phases of the menstrual cycle in women with migraine, and its impact on the occurrence and severity of migraine attacks. Melatonin as an internally secreted substance, but also present naturally in many foods. It is possible to supplement melatonin in the form of pharmaceutical preparations, and it seems, to be a good complementary therapy (due to the lack of significant side effects and pharmacological interactions) in the treatment of migraine, especially: in women of childbearing age, in people taking multiple medications for other diseases, as well as those sensitive to pharmacotherapy.

Repeated inflammatory dural stimulation-induced cephalic allodynia causes alteration of gut microbial composition in rats

BACKGROUND

Gut microbial dysbiosis and gut-brain axis dysfunction have been implicated in the pathophysiology of migraine. However, it is unclear whether migraine-related cephalic allodynia could induce the alteration of gut microbial composition.

METHODS

A classic migraine rat model was established by repeated dural infusions of inflammatory soup (IS). Periorbital mechanical threshold and nociception-related behaviors were used to evaluate IS-induced cephalic allodynia and the preventive effect of topiramate. The alterations in gut microbial composition and potential metabolic pathways were investigated based on the results of 16 S rRNA gene sequencing. Microbiota-related short-chain fatty acids and tryptophan metabolites were detected and quantified by mass spectrometry analysis.

RESULTS

Repeated dural IS infusions induced cephalic allodynia (decreased mechanical threshold), migraine-like behaviors (increased immobility time and reduced moving distance), and microbial composition alteration, which were ameliorated by the treatment of topiramate. Decreased Lactobacillus was the most prominent biomarker genus in the IS-induced alteration of microbial composition. Additionally, IS infusions also enhanced metabolic pathways of the gut microbiota in butanoate, propanoate, and tryptophan, while the increased tryptophan-related metabolites indole-3-acetamide and tryptophol in feces could be the indicators.

CONCLUSIONS

Inflammatory dural stimulation-induced cephalic allodynia causes the alterations of gut microbiota profile and microbial metabolic pathways.

Supplementation with SCFAs Re-Establishes Microbiota Composition and Attenuates Hyperalgesia and Pain in a Mouse Model of NTG-Induced Migraine

Migraine is a common brain-disorder that affects 15% of the population. Converging evidence shows that migraine is associated with gastrointestinal disorders. However, the mechanisms underlying the interaction between the gut and brain in patients with migraine are not clear. In this study, we evaluated the role of the short-chain fatty acids (SCFAs) as sodium propionate (SP) and sodium butyrate (SB) on microbiota profile and intestinal permeability in a mouse model of migraine induced by nitroglycerine (NTG). The mice were orally administered SB and SP at the dose of 10, 30 and 100 mg/kg, 5 min after NTG intraperitoneal injections. Behavioral tests were used to evaluate migraine-like pain. Histological and molecular analyses were performed on the intestine. The composition of the intestinal microbiota was extracted from frozen fecal samples and sequenced with an Illumina MiSeq System. Our results demonstrated that the SP and SB treatments attenuated hyperalgesia and pain following NTG injection. Moreover, SP and SB reduced histological damage in the intestine and restored intestinal permeability and the intestinal microbiota profile. These results provide corroborating evidence that SB and SP exert a protective effect on central sensitization induced by NTG through a modulation of intestinal microbiota, suggesting the potential application of SCFAs as novel supportive therapies for intestinal disfunction associated with migraine.

Headache and immunological/autoimmune disorders: a comprehensive review of available epidemiological evidence with insights on potential underlying mechanisms

Several lines of evidence support a role of the immune system in headache pathogenesis, with particular regard to migraine. Firstly, alterations in cytokine profile and in lymphocyte subsets have been reported in headache patients. Secondly, several genetic and environmental pathogenic factors seem to be frequently shared by headache and immunological/autoimmune diseases. Accordingly, immunological alterations in primary headaches, in particular in migraine, have been suggested to predispose some patients to the development of immunological and autoimmune diseases. On the other hand, pathogenic mechanisms underlying autoimmune disorders, in some cases, seem to favour the onset of headache. Therefore, an association between headache and immunological/autoimmune disorders has been thoroughly investigated in the last years. The knowledge of this possible association may have relevant implications in the clinical practice when deciding diagnostic and therapeutic approaches. The present review summarizes findings to date regarding the plausible relationship between headache and immunological/autoimmune disorders, starting from a description of immunological alteration of primary headaches, and moving onward to the evidence supporting a potential link between headache and each specific autoimmune/immunological disease.

Effect of Oat β-Glucan on Affective and Physical Feeling States in Healthy Adults: Evidence for Reduced Headache, Fatigue, Anxiety and Limb/Joint Pains

The gastrointestinal (GI) side-effects of dietary fibers are recognized, but less is known about their effects on non-GI symptoms. We assessed non-GI symptoms in a trial of the LDL-cholesterol lowering effect of oat β-glucan (OBG). Participants (n = 207) with borderline high LDL-cholesterol were randomized to an OBG (1 g OBG, n = 104, n = 96 analyzed) or Control (n = 103, n = 95 analyzed) beverage 3-times daily for 4 weeks. At screening, baseline, 2 weeks and 4 weeks participants rated the severity of 16 non-GI symptoms as none, mild, moderate or severe. The occurrence and severity (more or less severe than pre-treatment) were compared using chi-squared and Fisher's exact test, respectively. During OBG treatment, the occurrence of exhaustion and fatigue decreased versus baseline (p < 0.05). The severity of headache (2 weeks, p = 0.032), anxiety (2 weeks p = 0.059) and feeling cold (4 weeks, p = 0.040) were less on OBG than Control. The severity of fatigue and hot flashes at 4 weeks, limb/joint pain at 2 weeks and difficulty concentrating at both times decreased on OBG versus baseline. High serum c-reactive-protein and changes in c-reactive-protein, oxidized-LDL, and GI-symptom severity were associated with the occurrence and severity of several non-GI symptoms. These data provide preliminary, hypothesis-generating evidence that OBG may reduce several non-GI symptoms in healthy adults.

A link between gastrointestinal disorders and migraine: Insights into the gut-brain connection

Background

Migraine is a complex, multifaceted, and disabling headache disease that is often complicated by gastrointestinal (GI) conditions, such as gastroparesis, functional dyspepsia, and cyclic vomiting syndrome (CVS). Functional dyspepsia and CVS are part of a spectrum of disorders newly classified as disorders of gut–brain interaction (DGBI). Gastroparesis and functional dyspepsia are both associated with delayed gastric emptying, while nausea and vomiting are prominent in CVS, which are also symptoms that commonly occur with migraine attacks. Furthermore, these gastric disorders are comorbidities frequently reported by patients with migraine. While very few studies assessing GI disorders in patients with migraine have been performed, they do demonstrate a physiological link between these conditions.

Objective

To summarize the available studies supporting a link between GI comorbidities and migraine, including historical and current scientific evidence, as well as provide evidence that symptoms of GI disorders are also observed outside of migraine attacks during the interictal period. Additionally, the importance of route of administration and formulation of migraine therapies for patients with GI symptoms will be discussed.

Methods

A literature search of PubMed for articles relating to the relationship between the gut and the brain with no restriction on the publication year was performed. Studies providing scientific support for associations of gastroparesis, functional dyspepsia, and CVS with migraine and the impact these associations may have on migraine treatment were the primary focus. This is a narrative review of identified studies.

Results

Although the association between migraine and GI disorders has received very little attention in the literature, the existing evidence suggests that they may share a common etiology. In particular, the relationship between migraine, gastric motility, and vomiting has important clinical implications in the treatment of migraine, as delayed gastric emptying and vomiting may affect oral dosing compliance, and thus, the absorption and efficacy of oral migraine treatments.

Conclusions

There is evidence of a link between migraine and GI comorbidities, including those under the DGBI classification. Many patients do not find adequate relief with oral migraine therapies, which further necessitates increased recognition of GI disorders in patients with migraine by the headache community.

Calcitonin Gene-Related Peptide Receptor Antagonists (Gepants) for the Acute Treatment of Nausea in Episodic Migraine: A Systematic Review and Meta-Analysis

OBJECTIVE

To synthesize the evidence on the efficacy of calcitonin gene-related peptide receptor antagonists (gepants) from all clinical trials addressing nausea treatment for episodic migraine.

INTRODUCTION

Nausea is one of the most bothersome symptoms in patients with migraine. The most bothersome symptom is part of the outcomes explored in clinical trials.

METHODS

Published clinical trials for this project were identified via searches of 4 bibliographic databases: PubMed (includes MEDLINE), Embase, Web of Science, and the Cochrane Library. Individual search strategies included terms related to calcitonin gene-related peptide, nausea, and vomiting. Random-effects meta-analysis was conducted to estimate the overall efficacy of gepants for nausea treatment. Heterogeneity, publication bias, small-study bias, and potential confounders were explored using Galbraith plot, sensitivity analysis, meta-regression, and Egger's regression tests. Cumulative meta-analysis was done to detect temporal trend from accumulating trials.

RESULTS

The meta-analysis involved 23,008 participants in 65 clinical trials from 14 published articles; 10,770 subjects participated in gepant treatment arms while 12,238 subjects participated in placebo or non-gepant arms (85% females, mean age 41 years in both arms). Nearly all studies used a 2-hour incidence of nausea as an outcome measure. An overall combined effect size with an odds ratio of 1.29 (95% CI 1.18, 1.40, P = .001; I²  = 42.8%) showed the efficacy of gepants for the treatment of nausea in episodic migraine. Galbraith plot demonstrated that 98.4% of studies were within 2 standard deviations from the regression line, indicating lack of significant heterogeneity and outliers. Meta-analysis results were robust to sensitivity analysis, small-study bias, and publication bias (Kendall's Tau -0.09, P = .29; Egger's regression P = .67). Meta-regression showed that both age and sex ratio were not confounding the meta-analysis (omnibus P = .69). Cumulative meta-analysis indicated that the effect size remained stable for studies conducted after 2011, with accumulating evidence continuing to favor efficacy of gepants for the treatment of nausea in episodic migraine.

CONCLUSION

There is sufficient evidence to support the efficacy of gepants for the treatment of nausea in episodic migraine. Future research may focus on examining this efficacy in under-represented patient populations (males, older age groups) and in chronic migraine.

Gut-brain Axis and migraine headache: a comprehensive review

The terminology "gut-brain axis "points out a bidirectional relationship between the GI system and the central nervous system (CNS). To date, several researches have shown that migraine is associated with some gastrointestinal (GI) disorders such as Helicobacter pylori (HP) infection, irritable bowel syndrome (IBS), and celiac disease (CD). The present review article aims to discuss the direct and indirect evidence suggesting relationships between migraine and the gut-brain axis. However, the mechanisms explaining how the gut and the brain may interact in patients with migraine are not entirely clear. Studies suggest that this interaction seems to be influenced by multiple factors such as inflammatory mediators (IL-1β, IL-6, IL-8, and TNF-α), gut microbiota profile, neuropeptides and serotonin pathway, stress hormones and nutritional substances. Neuropeptides including CGRP, SP, VIP, NPY are thought to have antimicrobial impact on a variety of the gut bacterial strains and thus speculated to be involved in the bidirectional relationship between the gut and the brain. According to the current knowledge, migraine headache in patients harboring HP might be improved following the bacteria eradication. Migraineurs with long headache history and high headache frequency have a higher chance of being diagnosed with IBS. IBS and migraine share some similarities and can alter gut microflora composition and thereby may affect the gut-brain axis and inflammatory status. Migraine has been also associated with CD and the condition should be searched particularly in patients with migraine with occipital and parieto-occipital calcification at brain neuroimaging. In those patients, gluten-free diet can also be effective in reducing migraine frequency. It has also been proposed that migraine may be improved by dietary approaches with beneficial effects on gut microbiota and gut-brain axis including appropriate consumption of fiber per day, adhering to a low glycemic index diet, supplementation with vitamin D, omega-3 and probiotics as well as weight loss dietary plans for overweight and obese patients.

Effects of Diet Based on IgG Elimination Combined with Probiotics on Migraine Plus Irritable Bowel Syndrome

Several research studies have revealed that migraine has a solid link with gastrointestinal diseases especially irritable bowel syndrome (IBS). This study was carried out to investigate therapeutic potential of diet based on IgG elimination combined with probiotics on migraine plus irritable bowel syndrome. A total of 60 patients diagnosed with migraine plus IBS were recruited for the study. IgG antibodies against 266 food varieties were detected by ELISA. Then, the subjects were randomized into three groups for treatment of IgG elimination diet or probiotics or diet combined with probiotics. Migraine symptom, gut function score, medication use, and serum serotonin level were measured at baseline, 7 weeks, and 14 weeks. Improvement of migraine and gut symptom was achieved at a certain time point. Reduced use of over-the-counter- (OTC-) analgesics was seen in all groups. However, use of triptans did not show significant difference. An increased serum serotonin level was seen in subjects treated with elimination diet and elimination diet combined with probiotics. IgG elimination diet combined with probiotics may be beneficial to migraine plus IBS. It may provide new insight by understanding the intricate relationship between migraine and gastrointestinal diseases.

Gut Microbiota Dysbiosis Enhances Migraine-Like Pain Via TNFα Upregulation

Migraine is one of the most disabling neurological diseases worldwide; however, the mechanisms underlying migraine headache are still not fully understood and current therapies for such pain are inadequate. It has been suggested that inflammation and neuroimmune modulation in the gastrointestinal tract could play an important role in the pathogenesis of migraine headache, but how gut microbiomes contribute to migraine headache is unclear. In the present study, we investigated the effect of gut microbiota dysbiosis on migraine-like pain using broad-spectrum antibiotics and germ-free (GF) mice. We observed that antibiotics treatment-prolonged nitroglycerin (NTG)-induced acute migraine-like pain in wild-type (WT) mice and the pain prolongation was completely blocked by genetic deletion of tumor necrosis factor-alpha (TNFα) or intra-spinal trigeminal nucleus caudalis (Sp5C) injection of TNFα receptor antagonist. The antibiotics treatment extended NTG-induced TNFα upregulation in the Sp5C. Probiotics administration significantly inhibited the antibiotics-produced migraine-like pain prolongation. Furthermore, NTG-induced migraine-like pain in GF mice was markedly enhanced compared to that in WT mice and gut colonization with fecal microbiota from WT mice robustly reversed microbiota deprivation-caused pain enhancement. Together, our results suggest that gut microbiota dysbiosis contributes to chronicity of migraine-like pain by upregulating TNFα level in the trigeminal nociceptive system.

Potential Protective Mechanisms of Ketone Bodies in Migraine Prevention

An increasing amount of evidence suggests that migraines are a response to a cerebral energy deficiency or oxidative stress levels that exceed antioxidant capacity. The ketogenic diet (KD), a diet mimicking fasting that leads to the elevation of ketone bodies (KBs), is a therapeutic intervention targeting cerebral metabolism that has recently shown great promise in the prevention of migraines. KBs are an alternative fuel source for the brain, and are thus likely able to circumvent some of the abnormalities in glucose metabolism and transport found in migraines. Recent research has shown that KBs-D-β-hydroxybutyrate in particular-are more than metabolites. As signalling molecules, they have the potential to positively influence other pathways commonly believed to be part of migraine pathophysiology, namely: mitochondrial functioning, oxidative stress, cerebral excitability, inflammation and the gut microbiome. This review will describe the mechanisms by which the presence of KBs, D-BHB in particular, could influence those migraine pathophysiological mechanisms. To this end, common abnormalities in migraines are summarised with a particular focus on clinical data, including phenotypic, biochemical, genetic and therapeutic studies. Experimental animal data will be discussed to elaborate on the potential therapeutic mechanisms of elevated KBs in migraine pathophysiology, with a particular focus on the actions of D-BHB. In complex diseases such as migraines, a therapy that can target multiple possible pathogenic pathways seems advantageous. Further research is needed to establish whether the absence/restriction of dietary carbohydrates, the presence of KBs, or both, are of primary importance for the migraine protective effects of the KD.

Migraine associated with gastrointestinal disorders: A pathophysiological explanation

BACKGROUND

Migraine is a highly prevalent, disabling, and costly disorder worldwide. From a long time ago, headaches have been known to be associated with gastrointestinal (GI) disorders. Headaches originating from gastric complaints were appreciated by Persian Medicine (PM) scholars. Today, functional GI disorders are shown to have high comorbidity with migraines; however, a causal relationship is not accepted today and pathophysiological explanations for this comorbidity are scarce. Therefore, based on the PM philosophy and the existing evidence, we aimed to propose an explanation for the co-morbidity of migraine and GI disorders.

SUMMARY

Noxious stimuli from the GI tract are relayed to the nucleus tractus solitarius (NTS) in the brain stem, which is located close to the trigeminal nucleus caudalis (TNC). TNC has shown projections to (NTS) through which frequent GI stimuli may antidromically reach the TNC and finally result in neurogenic inflammation. In addition, immune products, particularly histamine, are released in the submucosa of the GI tract and absorbed into the systemic circulation, which renders migraineurs more prone to attacks.

Migraine, Cyclic Vomiting Syndrome, and Other Gastrointestinal Disorders

PURPOSE OF REVIEW

Cyclic vomiting syndrome (CVS) is a chronic functional gastrointestinal disorder characterized by episodic nausea and vomiting and is diagnosed using Rome IV criteria. CVS is being recognized more frequently in adults with a prevalence of 2%. It is associated with several functional disorders like autonomic dysfunction, anxiety, and depression, but the strongest association is with migraine. We will elucidate the close relationship between migraine and CVS and briefly discuss its association with other gastrointestinal disorders.

RECENT FINDINGS

We highlight similarities in pathophysiology, clinical presentation, and response to medications between CVS and migraine (tricyclic antidepressants, triptans, antiepileptics). We also discuss novel therapies like CGRP inhibitors which are effective in migraine and have potential for adaptation in patients with CVS. Using migraine as a template should enable investigators to elucidate the mechanisms underlying this disorder, develop novel therapies, and direct future research in CVS.

[Abdominal pain in migraine patients]

AIM

To study the frequency of comorbid abdominal pain in migraine patients and the influence of that symptom on the formation of disease phenotype.

MATERIAL AND METHODS

Clinical features of migraine were studied in 66 patients with episodic migraine and 40 patients with chronic migraine. Presence of pain, intensity, duration of seizure-associated abdominal pain and interictal abdominal pain were assessed.

RESULTS AND CONCLUSION

The frequency of abdominal pain in the painful phase of migraine was >11% and did not depend on the type of migraine. Pain in the abdomen were reported by 88% of patients, with the increase in the frequency in patients with chronic migraine. The intensity and frequency of abdominal pain did not depend on organic pathology of the digestive system. Correlations between the intensity and duration of abdominal pain during the migraine attack phase (k=0.59), between the intensity of associated pain and maladjustment severity (k=0.59), and also between the abdominal pain intensity during the painful phase and in the interictal period were identified. Allodynia developed more frequently in patients with abdominal pain between migraine attacks (РF=0.005). Also relationships between the level of intensity of interictal abdominal pain and the rates of alexithymia (k=0.24), anxiety (k=0.29) and depression (k=0.25) were revealed. The association of abdominal pain with disease severity and allodynia suggests similar development of these symptoms.

Migraine, Celiac Disease and Intestinal Microbiota

Investigators from four European tertiary care hospitals (in Paris, France; Milan, Udine and Perugia, Italy) performed a case-control study of children and adolescents aged 6 to 17 years diagnosed with primary headaches in the emergency department by a pediatric neurologist using the validated ICHD-3 criteria.

Effects of Changing the Amount and Source of Dietary Carbohydrates on Symptoms and Dietary Satisfaction Over a 1-Year Period in Subjects with Type 2 Diabetes: Canadian Trial of Carbohydrates in Diabetes (CCD)

OBJECTIVES

To determine the long-term effects of changing the amount or source of dietary carbohydrate on quality of life (QOL), symptoms and dietary satisfaction in people with type 2 diabetes.

METHODS

Subjects with diabetes treated by diet alone (n=162) were randomly assigned to high-carbohydrate/high-glycemic-index (HGI) diets; high-carbohydrate/low-glycemic-index (LGI) diets; or lower-carbohydrate/high-monounsaturated-fat (LC) diets for 1 year. We measured QOL at baseline and at study's end, and we measured symptoms and dietary satisfaction quarterly.

RESULTS

The HGI, LGI and LC diets contained, respectively, 47±1, 52±1 and 40±1% energy carbohydrate; 30±1, 27±1 and 40±1% fat with GI 64±0.4, 55±0.4 and 59±0.4. Significantly more participants reported increased flatulence on LGI than on LC and HGI diets at 3 months (41%, 19%, 14%; p<0.05), but not at 12 months (29%, 17%, 17%; ns). Abdominal distension was more severe (46% vs. 14%, 19%; p<0.05), and headache less severe (8% vs. 22%, 23%; p<0.05) on LGI than on both other diets. Increased appetite was more severe on LC (33%) than on HGI diets (14%, p<0.05). Joint/limb pains were less severe on LGI (16%) than HGI (28%) diets. LC elicited more severe gloomy thoughts (23%) than LGI (4%; p<0.05) but greater dietary-satisfaction (70%; p<0.05) than LGI (40%) and HGI (48%) diets. For all diets, glycated hemoglobin (A1C) levels increased less in those who gained less weight, had less increased appetite and were more satisfied with the enjoyment obtained from eating.

CONCLUSIONS

Each diet elicited increased severity of 1 or more symptoms than the other diets. Although overall dietary satisfaction was greater on the 40% carbohydrate diet than on the 50% carbohydrate diet, the LGI diet was no less satisfying than the HGI diet. Changes in appetite and dietary satisfaction may influence body weight and glycemic control, or vice-versa.

Gastrointestinal disorders associated with migraine: A comprehensive review

Migraine is a recurrent and commonly disabling primary headache disorder that affects over 17% of women and 5%-8% of men. Migraine susceptibility is multifactorial with genetic, hormonal and environmental factors all playing an important role. The physiopathology of migraine is complex and still not fully understood. Many different neuropeptides, neurotransmitters and brain pathways have been implicated. In connection with the myriad mechanisms and pathways implicated in migraine, a variety of multisystemic comorbidities (e.g., cardiovascular, psychiatric and other neurological conditions) have been found to be closely associated with migraine. Recent reports demonstrate an increased frequency of gastrointestinal (GI) disorders in patients with migraine compared with the general population. Helicobacter pylori infection, irritable bowel syndrome, gastroparesis, hepatobiliary disorders, celiac disease and alterations in the microbiota have been linked to the occurrence of migraine. Several mechanisms involving the gut-brain axis, such as a chronic inflammatory response with inflammatory and vasoactive mediators passing to the circulatory system, intestinal microbiota modulation of the enteric immunological milieu and dysfunction of the autonomic and enteric nervous system, have been postulated to explain these associations. However, the precise mechanisms and pathways related to the gut-brain axis in migraine need to be fully elucidated. In this review, we survey the available literature linking migraine with GI disorders. We discuss the possible physiopathological mechanisms, and clinical implications as well as several future areas of interest for research.