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

Investigating the causal association between systemic lupus erythematosus and migraine using Mendelian randomization analysis

OBJECTIVE

To assess whether systemic lupus erythematosus (SLE) may be genetically causally associated with migraine, including the two primary subtypes: migraine with aura (MWA) and migraine without aura (MWoA).

BACKGROUND

The association between SLE and migraine has been investigated extensively. Previous studies have shown a higher prevalence of migraine in patients with SLE, although the exact relationship remains unclear. This study investigated the potential causal association between SLE and migraine using the powerful analytical tool of Mendelian randomization (MR).

METHODS

We performed two-sample MR analysis of publicly available summary statistic datasets using inverse variance-weighted (IVW), weighted median, and MR-Egger methods based on an SLE genome-wide association study (GWAS; 5201 cases; 9066 controls; the exposure frequency is 36.5%) as an exposure and migraine GWAS (15,905 cases; 264,662 controls) in individuals with European ancestry as outcomes, focusing on the two migraine subtypes MWA (6780 cases; 264,662 controls) and MWoA (5787 cases; 264,662 controls). Thepleiotropy and heterogeneity were performed.

RESULTS

We selected 42 single-nucleotide polymorphisms from SLE GWAS as instrumental variables (IVs) for SLE on migraine, and 41 SNP IVs for SLE on MWA or MWoA. The IVW (odds ratio [OR] = 1.01, 95% confidence interval [CI] = [0.99, 1.03], p = 0.271), weighted median (OR = 1.00, 95% CI = [0.97, 1.03], p = 0.914), and MR-Egger (OR = 1.04, 95% CI = [0.99, 1.09], p = 0.153) methods showed no causal effect of SLE on migraine. A causal effect of SLE was observed on MWA (IVW: OR = 1.05, 95% CI = [1.02, 1.08], p = 0.001; weighted median: OR = 1.05, 95% CI = [1.01, 1.10], p = 0.018; MR-Egger: OR = 1.07, 95% CI = [1.01, 1.14], p = 0.035 and pIVW < 0.017 [Bonferroni correction]) but not MWoA (IVW: OR = 0.99, 95% CI = [0.96, 1.02], p = 0.331; weighted median: OR = 0.98, 95% CI = [0.94, 1.03], p = 0.496; MR-Egger: OR = 1.02, 95% CI = [0.95, 1.09], p = 0.652). The results showed no significant pleiotropy or heterogeneity.

CONCLUSION

Our MR analysis demonstrated the complex relationship between SLE and migraine, suggesting a potential effect of SLE on the risk of MWA but not MWoA. These findings can aid in the development of improved subtype-specific management of migraine in patients with SLE.

Headache disorders in multiple sclerosis: Is there an association? A systematic review and meta-analysis

OBJECTIVE

To look for any potential association of headache disorders with multiple sclerosis (MS).

BACKGROUND

The prevalence of headache disorders has been found to be increased in people with MS (pwMS), however, an association has not been established. Existing studies have provided conflicting results mostly because of methodological differences.

METHODS

PubMed, Embase and Scopus were searched to identify eligible studies. Studies were included if they were cross-sectional, case-control or cohort. Newcastle-Ottawa Scale (NOS) was used to assess the risk of bias of the included studies. Case-control, cross sectional or cohort studies that used the International Classification of Headache Disorders (ICHD)-2 or-3 criteria for headache diagnosis and Mc Donald or Poser criteria for MS diagnosis were included. Data were extracted using standardized data collection form. Meta-analysis was conducted by calculating the overall prevalence of headache disorders in pwMS as well as the association of headache disorders with MS. The Newcastle-Ottawa Scale (NOS), a tool for assessing the quality of non-randomized studies, was used to assess the quality of the included studies.

RESULTS

Twenty-three studies were included yielding a total of 5,440 MS patients and 28,0958 controls. The majority of them scored a NOS score between 5 and 6 (max 9), which indicates that they did not rank high in terms of quality, because most studies were cross-sectional and uncontrolled, and only one was prospective, controlled, and longitudinal, but with small population size. Pooled prevalence for all headache disorders, migraine and tension-type headache (TTH) in pwMS was 58 % (95 % CI 0.54-0.61), 30 % (95 % CI 0.25-0.34) and 19 % (95 % CI 0.15-0.23) respectively. A significant association between migraine and MS was found (OR = 2.02, 95 % CI = 1.14-3.57).

CONCLUSION

PwMS are twice as likely to experience migraine as controls, but the results need to be translated with caution since most of the studies included in the meta-analysis were of low or moderate quality. Larger prospective cohort, controlled, longitudinal studies are needed to confirm whether there is indeed an association between MS and migraine.

Prevalence of primary headaches in multiple sclerosis patients

BACKGROUND

Multiple sclerosis (MS) is the most common immune-mediated inflammatory disease of the central nervous system. It is characterized by symptoms such as visual disturbances, paresis with spasticity, paresthesia, numbness, and fatigue. However, several studies have shown a high prevalence of headaches in individuals with MS. Migraine and tension-type headaches are the most frequent types of headaches experienced by those with MS. Additionally, the role of MS disease-modifying agents must be considered. These agents have different modes of action and side effect profiles, and their use may sometimes trigger headaches in patients with MS.

OBJECTIVES

This study aimed to explore the prevalence and clinical characteristics of primary headaches in MS patients. The relationship between headache and clinical features of MS (Course of MS, duration, EDSS, brain imaging and DMD) are also investigated.

SUBJECTS AND METHODS

Two hundred and eighty-one MS patients diagnosed according to according to the 2017 revisions to the McDonald Criteria were included in the study. Data was collected from the MS unit medical records and from the interview with the patients. Patients with reported headaches are asked to recall their headache characteristics and patterns using an interviewer administered Arabic language-structured validated questionnaire.

RESULTS

The median age of patients was 33 years old, with a range of 22-55. Tension-type headache (TTH) was more common in males, patients with more severe disability (EDSS ≥ 3), and those with SPMS and PPMS phenotypes. Additionally, patients on rituximab or cyclophosphamide therapy were more likely to have TTH. On the other hand, females, patients with milder disability (EDSS < 3), and those with RRMS phenotype were more likely to have migraine. This was also true for patients with MRI lesions involving the periaqueductal gray, and those receiving INF or fingolimod (P < 0.05). Periaqueductal gray matter lesions were found in the MRI of 48 patients (40 %) who experienced headaches on more than 10 days per month. Sensorimotor lesions in the brain were found in 55 patients (53.4 %) with severe headaches (p-value < 0.001). Interferons were associated with an increased risk of worsening preexisting headaches and the appearance of de novo headaches related to its intake (odds ratio: 2.84, 3.72; relative risk: 1.63, 2.04; p-value = 0.03, < 0.001, respectively). On the other hand, rituximab was associated with a decreased risk of worsening preexisting headaches and the appearance of de novo headaches related to its intake (odds ratio: 0.04, 0.09; relative risk: 0.11, 0.18; p-value = < 0.001, < 0.001, respectively).

CONCLUSION

Primary headaches are a common occurrence in patients with MS. Migraines and tension-type headaches (TTH) are among the most prevalent types. It has been observed that interferon can exacerbate preexisting headaches and even cause new ones. Additionally, the location of MS plaques may play a role in the frequency and severity of headaches.

Treatment patterns of galcanezumab versus standard of care preventive migraine medications over 24 months: a US retrospective claims study

OBJECTIVE

To describe long-term (24-month) treatment patterns of patients initiating galcanezumab versus standard of care (SOC) preventive migraine treatments including anticonvulsants, beta-blockers, antidepressants, and onabotulinumtoxinA using administrative claims data.

METHODS

This retrospective cohort study, which used Optum de-identified Market Clarity data, included adults with migraine with ≥1 claim for galcanezumab or SOC preventive migraine therapy (September 1, 2018 - March 31, 2020) and continuous database enrollment for 12 months before (baseline) and 24 months after (follow-up) the index date (date of first claim). Baseline patient demographics, clinical characteristics, and treatment patterns were analyzed after 24-month follow-up, including adherence (measured as the proportion of days covered [PDC]), persistence, discontinuation (≥60-day gap), restart, and treatment switch. Propensity score matching (1:1) was used to balance the galcanezumab and SOC cohorts.

RESULTS

The study included 2307 matched patient pairs with 24-month follow-up. The mean age across cohorts was 44.5 years (females: ∼87%). Patients in the galcanezumab versus SOC cohort demonstrated greater treatment adherence (PDC: 48% vs. 38%), with more patients considered adherent (PDC ≥80%: 26.6% vs. 20.7%) and persistent (322.1 vs. 236.4 d) (all p < .001). After 24-month follow-up, fewer galcanezumab-treated patients had discontinued compared with SOC-treated patients (80.1% vs. 84.7%; p < .001), of which 41.3% and 39.6% switched to a non-index medication, respectively. The most prevalent medication patients switched to in both cohorts was erenumab. Significantly greater proportions of patients who initiated galcanezumab versus SOC medications switched to fremanezumab (p < .001) and onabotulinumtoxinA (p = .016).

CONCLUSION

Patients who initiated galcanezumab for migraine prevention had higher treatment adherence and persistence compared with those who initiated SOC medications after 24-month follow-up.

[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.

No association between blood-based markers of immune system and migraine status: a population-based cohort study

BACKGROUND

Although some evidence implicates the immune system in migraine attacks, its role during attack-free periods remains largely unexplored. Therefore, we assessed the association between the immune system and migraine status.

METHODS

From the population-based Rotterdam Study, we included 6593 participants who underwent blood sampling and migraine assessments. In the blood samples, we measured white blood-cell-based immune markers. As a marker for the innate immune system, granulocyte and platelet counts were determined, whereas lymphocyte counts were used as a marker for the adaptive immune system. Migraine was assessed using a validated questionnaire based on ICHD-2 criteria. We investigated associations between blood-cell counts and migraine using logistic regression models adjusting for age, sex and other variables.

RESULTS

Mean age of participants was 65.6 ± 11.2 years and 56.7% were female. The lifetime prevalence of migraine was 15.1% (995/6593). We found no statistically significant associations between granulocyte (odds ratio [OR] per standard deviation increase 1.01 95% Confidence Interval [CI]: 0.93-1.09), platelet (OR 1.01 CI: 0.94-1.09) or lymphocyte counts (OR 1.01 CI: 0.93-1.08) and migraine status.

CONCLUSIONS

Our results do not support an association between white blood-cell-based immunity markers and migraine status.

Effectiveness of transcranial direct current stimulation (tDCS) as adjunctive treatment for chronic headache in adults with clinically stable systemic lupus erythematosus (SHADE): a randomised double-blind multiarm sham controlled clinical trial

BACKGROUND

Chronic headache is a 'silent' neuropsychiatric systemic lupus erythematosus symptom with heterogeneous prevalence, potentially reaching 54.4%. It may reduce quality of life by increasing the likelihood of depression and sleep disturbance. While pharmacotherapy remains the first-line treatment, the current management is still challenging and needs other non-invasive modalities. An effective, tolerable and disease-specific treatment modality including transcranial direct current stimulation (tDCS) is considered to reduce the frequency of chronic headaches, including in SLE. Until recently, there was no standard protocol for tDCS in treating headaches.

METHODS AND ANALYSIS

SHADE is a single-centre randomised double-blind multiarm sham-controlled trial for adults with clinically stable SLE, chronic headaches and without history of traumatic brain injury, brain infection, stroke or brain tumour. Random allocation is conducted to 88 subjects into 3 treatment groups (administration at primary motor, primary sensory and dorsolateral prefrontal cortex) and control group in 1:1:1:1 ratio. The primary endpoint is reduced number of headache days after adjunctive tDCS. The secondary endpoints are reduced headache intensity, increased quality of life, increased sleep quality, decreased depression and reduced analgesics use. The outcome is measured monthly until 3-month postintervention using headache diary, 36-Item Short Form Survey, Chronic Headache Quality of Life Questionnaire, Pittsburgh Sleep Quality Index and Mini International Neuropsychiatry Interview version 10 (MINI ICD 10). Intention-to-treat analysis will be performed to determine the best tDCS electrode placement.

ETHICS AND DISSEMINATION

Ethical approval had been obtained from the local Institutional Review Board of Faculty of Medicine Universitas Indonesia. Results will be published through scientific relevant peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT05613582.

Severe Headache in Primary Sjögren's Syndrome Responded to Rituximab

Introduction

Primary Sjögren syndrome (pSS) is an immune systemic disease, that may affect the central nervous system. A severe headache unresponsive to treatment is the headache which is persistently nonresponsive to narcotic analgesics.

Case presentation

A 48-year-old woman with a 10-year history of pSS was seen in January 2021, complaining of a headache one week previously. The headache was characterised by a dull persistent pressing intensity and was not responding to paracetamol, NSAIDs or codeine. She had no previous history, nor family history. Physical examination revealed bilateral parotid glands enlargement. Laboratory tests showed anaemia, and elevated levels of erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), with positive anti-La and anti-Ro antibodies. She was given topical treatment and different doses of Predlone, in addition to methotrexate10 mg/week. She had received three pulses of methylprednisolone and was started on azathioprine with a mild response to the headaches, so she received two initial IV doses of rituximab 375 mg/m2, then every 2 weeks, with a clinical and laboratory response. Two years later, she had no headache.

Discussion

Headache that may presented in pSS are tension headaches, migraines and cluster headaches. The therapy is disease-modifying antirheumatic drugs, hydroxychloroquine, glucocorticoids and biotherapeutics. Rituximab is used in the treatment of some patients with pSS, especially where it can affect systemic symptoms.

Conclusion

Rituximab treatment may be an option for severe headache in patients with pSS. The mechanism is unknown but may be due to depletion of brain auto-reactive B cells. Further research is needed.

LEARNING POINTS

An unresponsive headache in a patient with primary Sjögren's syndrome treated with tryptophan, opioids and NSAIDs responded successfully to B-cell depletion with rituximab.We hypothesise that brain-autoreactive B cells were involved in the pathogenesis of the headache.

Migraine in multiple sclerosis patients: potential links and treatment approach

INTRODUCTION

Migraine has been reported to be twice as prevalent in patients with multiple sclerosis (MS) compared to the non-MS population. However, prospective, controlled studies that could lead to robust conclusions are still lacking.

AREAS COVERED

Treatment of migraine in patients with MS can be challenging. Comorbidities need to be assessed and managed early, and preventive treatment should be initiated when indicated. Caution is warranted regarding the selection of the preventive medication since certain agents can magnify MS symptoms and particularly cognitive symptoms. This paper aims to discuss the association of MS and migraine, shed light on distinguishing points and red flags, as well as offer practical advice on the selection of treatment according to patients' characteristics.

EXPERT OPINION

A holistic approach including pharmacological and non-pharmacological modifications is required to treat migraine in patients with MS effectively. Anti-CGRP monoclonal antibodies are a promising option due to limited drug-to-drug interactions; however, larger prospective studies are required to draw robust conclusions on the concomitant use of anti-CGRPs with MS disease modifying treatments. Early migraine preventive treatment might be needed to reduce the burden of disease in patients with MS.

Advanced brain MRI may help understand the link between migraine and multiple sclerosis

BACKGROUND

There is a clinical association between migraine and multiple sclerosis.

MAIN BODY

Migraine and MS patients share similar demographics, with the highest incidence among young, female and otherwise healthy patients. The same hormonal constellations/changes trigger disease exacerbation in both entities. Migraine prevalence is increased in MS patients, which is further enhanced by disease-modifying treatment. Clinical data show that onset of migraine typically starts years before the clinical diagnosis of MS, suggesting that there is either a unidirectional relationship with migraine predisposing to MS, and/or a "shared factor" underlying both conditions. Brain imaging studies show white matter lesions in both MS and migraine patients. Neuroinflammatory mechanisms likely play a key role, at least as a shared downstream pathway. In this review article, we provide an overview of the literature about 1) the clinical association between migraine and MS as well as 2) brain MRI studies that help us better understand the mechanistic relationship between both diseases with implications on their underlying pathophysiology.

CONCLUSION

Studies suggest a migraine history predisposes patients to develop MS. Advanced brain MR imaging may shed light on shared and distinct features, while helping us better understand mechanisms underlying both disease entities.

Migraine and risk of rheumatoid arthritis: A systematic review and meta-analysis of observational studies

Background

Exposure to Migraine may be one of the risk factors for the onset of rheumatoid arthritis (RA), while the relationship between the two is debatable. In this study, the connection between migraine and the risk of RA was investigated using a systematic review and meta-analysis of the pertinent literature.

Methods

Up to July 2022, the PubMed, EMBASE, Web of Science (WOS), and scopus databases were employed to search for observational studies on the risk of RA in migraineurs. The effect sizes were pooled using a random-effects model or a fixed-effects model.

Results

Out of 2345 records, 5 studies (3 case and control studies and 2 cohort studies) were identified and included in the meta-analysis. According to a pooled analysis, migraine sufferers had a higher chance of developing RA (pooled adjusted effect estimate: 1.94, 95% confidence interval: 1.74-2.17; p < 0.01).

Conclusions

Migraine can be legitimately regarded as a risk factor for RA since this study demonstrated a relationship between migraine and RA. This conclusion should be treated with caution due to low power and precision. Rigorous design and larger sample sizes of studies are needed to verify the findings.

Cross-trait analyses identify shared genetics between migraine, headache, and glycemic traits, and a causal relationship with fasting proinsulin

The co-occurrence of migraine and glycemic traits has long been reported in observational epidemiological studies, but it has remained unknown how they are linked genetically. We used large-scale GWAS summary statistics on migraine, headache, and nine glycemic traits in European populations to perform cross-trait analyses to estimate genetic correlation, identify shared genomic regions, loci, genes, and pathways, and test for causal relationships. Out of the nine glycemic traits, significant genetic correlation was observed for fasting insulin (FI) and glycated haemoglobin (HbA1c) with both migraine and headache, while 2-h glucose was genetically correlated only with migraine. Among 1703 linkage disequilibrium (LD) independent regions of the genome, we found pleiotropic regions between migraine and FI, fasting glucose (FG), and HbA1c, and pleiotropic regions between headache and glucose, FI, HbA1c, and fasting proinsulin. Cross-trait GWAS meta-analysis with glycemic traits, identified six novel genome-wide significant lead SNPs with migraine, and six novel lead SNPs with headache (Pmeta < 5.0 × 10-8 and Psingle-trait < 1 × 10-4), all of which were LD-independent. Genes with a nominal gene-based association (Pgene ≤ 0.05) were significantly enriched (overlapping) across the migraine, headache, and glycemic traits. Mendelian randomisation analyses produced intriguing, but inconsistent, evidence for a causal relationship between migraine and headache with multiple glycemic traits; and consistent evidence suggesting increased fasting proinsulin levels may causally decrease the risk of headache. Our findings indicate that migraine, headache, and glycemic traits share a common genetic etiology and provide genetic insights into the molecular mechanisms contributing to their comorbid relationship.

Clinical Characteristics of Headache in Multiple Sclerosis Patients: A Cross-Sectional Study

Primary headaches are known to be associated with multiple sclerosis (MS), but previous studies concerning this relationship are not conclusive. Nowadays, there are no studies assessing the prevalence of headaches in Polish MS patients. The aim of the study was to assess the prevalence and characterise headaches in MS patients treated with disease-modifying therapies (DMTs). In a cross-sectional study of 419 consecutive RRMS patients, primary headaches were diagnosed according to the International Classification of Headache Disorders (ICHD-3) criteria. Primary headaches were observed in 236 (56%) of RRMS patients, with a higher prevalence in women (ratio of 2:1). The most common was migraine 174 (41%) (migraine with aura 80 (45%), migraine without aura 53 (30%), and probable migraine without aura 41 (23%); less frequent was tension-type headache 62 (14%). Female sex was a risk factor for migraines but not for tension-type headaches (p = 0.002). Migraines mostly started before MS onset (p = 0.023). Migraine with aura was associated with older age, longer disease duration (p = 0.028), and lower SDMT (p = 0.002). Longer DMT time was associated with migraine (p = 0.047), particularly migraine with aura (p = 0.035). Typical for migraine with aura were headaches during clinical isolated syndrome (CIS) (p = 0.001) and relapses (p = 0.025). Age and type of CIS, oligoclonal band presence, family MS history, EDSS, 9HTP, T25FW, and type of DMT did not correlate with headache. Headaches are present in more than half of MS patients treated with DMTs; migraines occur almost three times more frequently than tension-type headaches. Migraines with aura headaches during CIS and relapses are typical. Migraine in MS patients had high severity and typical migraine characteristics. DMTs had no correlation with the presence or type of headache.

Clinical Implications of the Association between Respiratory and Gastrointestinal Disorders in Migraine and Non-Migraine Headache Patients

Headaches, particularly migraine, are associated with gastrointestinal (GI) disorders. In addition to the gut-brain axis, the lung-brain axis is suspected to be involved in the relationship between pulmonary microbes and brain disorders. Therefore, we investigated possible associations of migraine and non-migraine headaches (nMH) with respiratory and GI disorders using the clinical data warehouse over 11 years. We compared data regarding GI and respiratory disorders, including asthma, bronchitis, and COPD, among patients with migraine, patients with nMH, and controls. In total, 22,444 patients with migraine, 117,956 patients with nMH, and 289,785 controls were identified. After adjustment for covariates and propensity score matching, the odds ratios (ORs) for asthma (1.35), gastroesophageal reflux disorder (1.55), gastritis (1.90), functional GI disorder (1.35), and irritable bowel syndrome (1.76) were significantly higher in patients with migraine than in controls (p = 0.000). The ORs for asthma (1.16) and bronchitis (1.33) were also significantly higher in patients with nMH than in controls (p = 0.0002). When the migraine group was compared with the nMH group, only the OR for GI disorders was statistically significant. Our findings suggest that migraine and nMH are associated with increased risks of GI and respiratory disorders.

IVIg-induced headache: prospective study of a large cohort with neurological disorders

BACKGROUND

Intravenous immune globulin (IVIg) is frequently used in some neurological diseases and is also the first-line therapy in Guillain-Barré syndrome, chronic inflammatory demyelinating polyneuropathy, and multifocal motor neuropathy. We aimed to evaluate the frequency and characteristics of headaches, which is one of the most common side effects of IVIg treatment.

METHODS

Patients who received IVIg treatment for neurological diseases were prospectively enrolled in 23 centers. Firstly, the characteristics of patients with and without IVIg-induced headaches were analyzed statistically. Then, patients with IVIg-induced headaches were classified into three subgroups determined by their history: no primary headache, tension-type headache (TTH), and migraine.

RESULTS

A total of 464 patients (214 women) and 1548 IVIg infusions were enrolled between January and August 2022. The frequency of IVIg-related headaches was 27.37% (127/464). A binary logistic regression analysis performed with significant clinical features disclosed that female sex and fatigue as a side effect were statistically more common in the IVIg-induced headache group. IVIg-related headache duration was long and affected daily living activities more in patients with migraine compared to no primary headache and TTH groups (p = 0.01, respectively).

CONCLUSION

Headache is more likely to occur in female patients receiving IVIg and those who develop fatigue as a side effect during the infusion. Clinicians' awareness of IVIg-related headache characteristics, especially in patients with migraine, may increase treatment compliance.

The putative role of neuroinflammation in the complex pathophysiology of migraine: From bench to bedside

The implications of neurogenic inflammation and neuroinflammation in the pathophysiology of migraine have been clearly demonstrated in preclinical migraine models involving several sites relevant in the trigemino-vascular system, including dural vessels and trigeminal endings, the trigeminal ganglion, the trigeminal nucleus caudalis as well as central trigeminal pain processing structures. In this context, a relevant role has been attributed over the years to some sensory and parasympathetic neuropeptides, in particular calcitonin gene neuropeptide, vasoactive intestinal peptide and pituitary adenylate cyclase-activating polypeptide. Several preclinical and clinical lines of evidence also support the implication of the potent vasodilator and messenger molecule nitric oxide in migraine pathophysiology. All these molecules are involved in vasodilation of the intracranial vasculature, as well as in the peripheral and central sensitization of the trigeminal system. At meningeal level, the engagement of some immune cells of innate immunity, including mast-cells and dendritic cells, and their mediators, has been observed in preclinical migraine models of neurogenic inflammation in response to sensory neuropeptides release due to trigemino-vascular system activation. In the context of neuroinflammatory events implicated in migraine pathogenesis, also activated glial cells in the peripheral and central structures processing trigeminal nociceptive signals seem to play a relevant role. Finally, cortical spreading depression, the pathophysiological substrate of migraine aura, has been reported to be associated with inflammatory mechanisms such as pro-inflammatory cytokine upregulation and intracellular signalling. Reactive astrocytosis consequent to cortical spreading depression is linked to an upregulation of these inflammatory markers. The present review summarizes current findings on the roles of immune cells and inflammatory responses in the pathophysiology of migraine and their possible exploitation in the view of innovative disease-modifying strategies.

Shared genetics and causal relationships between migraine and thyroid function traits

BACKGROUND

Epidemiological studies have reported a comorbid relationship between migraine and thyroid dysfunction.

METHODS

We investigated the genetic relationship between migraine and thyroid function traits using genome-wide association study (GWAS) data.

RESULTS

We found a significant genetic correlation (r_g) with migraine for hypothyroidism (r_g = 0.0608), secondary hypothyroidism (r_g = 0.195), free thyroxine (fT4) (r_g = 0.0772), and hyperthyroidism (r_g = -0.1046), but not thyroid stimulating hormone (TSH). Pairwise GWAS analysis revealed two shared loci with TSH and 11 shared loci with fT4. Cross-trait GWAS meta-analysis of migraine identified novel genome-wide significant loci: 17 with hypothyroidism, one with hyperthyroidism, five with secondary hypothyroidism, eight with TSH, and 15 with fT4. Of the genes at these loci, six (RERE, TGFB2, APLF, SLC9B1, SGTB, BTBD16; migraine + hypothyroidism), three (GADD45A, PFDN1, RSPH6A; migraine + TSH), and three (SSBP3, BRD3, TEF; migraine + fT4) were significant in our gene-based analysis (p_{Fisher's combined P-value} < 2.04 × 10^-6). In addition, causal analyses suggested a negative causal relationship between migraine and hyperthyroidism (p = 8.90 × 10^-3) and a positive causal relationship between migraine and secondary hypothyroidism (p = 1.30 × 10^-3).

CONCLUSION

These findings provide strong evidence for genetic correlation and suggest complex causal relationships between migraine and thyroid traits.

Cross-Trait Genetic Analyses Indicate Pleiotropy and Complex Causal Relationships between Headache and Thyroid Function Traits

Epidemiological studies have reported a comorbid relationship between headache and thyroid traits; however, little is known about the shared genetics and causality that contributes to this association. We investigated the genetic overlap and associations between headache and thyroid function traits using genome-wide association study (GWAS) data. We found a significant genetic correlation (rg) with headache and hypothyroidism (rg = 0.09, p = 2.00 × 10−4), free thyroxine (fT4) (rg = 0.08, p = 5.50 × 10−3), and hyperthyroidism (rg = −0.14, p = 1.80 × 10−3), a near significant genetic correlation with secondary hypothyroidism (rg = 0.20, p = 5.24 × 10−2), but not with thyroid stimulating hormone (TSH). Pairwise-GWAS analysis revealed six, 14, four and five shared (pleiotropic) loci with headache and hypothyroidism, hyperthyroidism, secondary hypothyroidism, and fT4, respectively. Cross-trait GWAS meta-analysis identified novel genome-wide significant loci for headache: five with hypothyroidism, three with secondary hypothyroidism, 12 with TSH, and nine with fT4. Of the genes at these loci, six (FAF1, TMX2-CTNND1, AARSD1, PLCD3, ZNF652, and C20orf203; headache-TSH) and six (HMGB1P45, RPL30P1, ZNF462, TMX2-CTNND1, ITPK1, SECISBP2L; headache-fT4) were significant in our gene-based analysis (pFisher’s combined p-value < 2.09 × 10−6). Our causal analysis suggested a positive causal relationship between headache and secondary hypothyroidism (p = 3.64 × 10−4). The results also suggest a positive causal relationship between hypothyroidism and headache (p = 2.45 × 10−3) and a negative causal relationship between hyperthyroidism and headache (p = 1.16 × 10−13). These findings suggest a strong evidence base for a genetic correlation and complex causal relationships between headache and thyroid traits.

Immunologic aspects of migraine: A review of literature

Migraine headaches are highly prevalent, affecting 15% of the population. However, despite many studies to determine this disease's mechanism and efficient management, its pathophysiology has not been fully elucidated. There are suggested hypotheses about the possible mediating role of mast cells, immunoglobulin E, histamine, and cytokines in this disease. A higher incidence of this disease in allergic and asthma patients, reported by several studies, indicates the possible role of brain mast cells located around the brain vessels in this disease. The mast cells are more specifically within the dura and can affect the trigeminal nerve and cervical or sphenopalatine ganglion, triggering the secretion of substances that cause migraine. Neuropeptides such as calcitonin gene-related peptide (CGRP), neurokinin-A, neurotensin (NT), pituitary adenylate-cyclase-activating peptide (PACAP), and substance P (SP) trigger mast cells, and in response, they secrete pro-inflammatory and vasodilatory molecules such as interleukin-6 (IL-6) and vascular endothelial growth factor (VEGF) as a selective result of corticotropin-releasing hormone (CRH) secretion. This stress hormone contributes to migraine or intensifies it. Blocking these pathways using immunologic agents such as CGRP antibody, anti-CGRP receptor antibody, and interleukin-1 beta (IL-1β)/interleukin 1 receptor type 1 (IL-1R1) axis-related agents may be promising as potential prophylactic migraine treatments. This review is going to summarize the immunological aspects of migraine.

Refractory Headaches

Medication overuse headache (MOH), new daily persistent headache (NDPH), and persistent refractory headache attributed to severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) infection represent a significant burden in terms of disability and quality of life, and a challenge in terms of definition, pathophysiology, and treatment. Regarding MOH, prevention without withdrawal is not inferior to prevention with withdrawal. Preventive medications like topiramate, onabotulinumtoxinA, and calcitonin gene-related peptide (CGRP) monoclonal antibodies improve chronic migraine with MOH regardless of withdrawal. The differential diagnosis of NDPH is broad and should be carefully examined. There are no guidelines for the treatment of NDPH, but options include a short course of steroids, nerve blocks, topiramate, nortriptyline, gabapentin, CGRP monoclonal antibodies, and onabotulinumtoxinA. The persistence of headache 3 months after SARS-CoV2 infection is a predictor of poor prognosis.

The Problem of Pain in Rheumatology: Clinical Profiles Associated With Concomitant Diagnoses With Chronic Overlapping Pain Conditions

OBJECTIVE

The chronification of pain is heterogeneous in rheumatology. Chronic overlapping pain conditions (COPCs) such as fibromyalgia, endometriosis, migraine, and back pain may co-occur with one another and in rheumatic diseases. We describe the sociodemographic and clinical profiles associated with concomitant COPCs among patients with rheumatic diseases.

METHODS

We retrospectively identified patients visiting rheumatology clinics at a single institution from 2010 to 2020 for five common rheumatic conditions: psoriatic arthritis (PsA), rheumatoid arthritis (RA), Sjögren syndrome (SjS), systemic lupus erythematosus (SLE), and systemic sclerosis (SSc). We compared sociodemographic, clinical, and lifestyle factors by rheumatic condition and by COPC status. We also report sex-stratified diagnosis of COPCs. The primary outcome was diagnostic validation of one or more COPCs.

RESULTS

We identified 5992 rheumatology patients: 846 with PsA, 2605 with RA, 956 with SjS, 975 with SLE, and 610 with SSc. Approximately 36-62% of patients had a concomitant COPC diagnosis. Patients with SjS had the highest prevalence (62%). Diagnosis of one or more COPCs was highest among Black patients and lowest among Asian patients. Patients using public insurance had a higher prevalence of one or more COPCs compared with those with private insurance. Patients with one or more COPCs had more depression and anxiety and more frequent emergency department visits, surgeries, and hospitalizations.

CONCLUSION

Our findings suggest that COPCs are strikingly common among patients with rheumatic disease and are associated with lower quality of life and greater health care needs. Future research may elucidate drivers of chronic pain and how to best address the unique analgesic needs of this multimorbid population.

Dural Immune Cells, CGRP, and Migraine

Migraine is the most common neurological disorder in the world, affecting 12% of the population. Migraine involves the central nervous system, trigeminal nerves and meninges. Recent advances have shown that targeting calcitonin gene-related peptide (CGRP) through either antibodies or small molecule receptor antagonists is effective at reducing episodic and chronic migraine episodes, but these therapeutics are not effective in all patients. This suggests that migraine does not have a singular molecular cause but is likely due to dysregulated physiology of multiple mechanisms. An often-overlooked part of migraine is the potential involvement of the immune system. Clinical studies have shown that migraine patients may have dysregulation in their immune system, with abnormal plasma cytokine levels either during the attack or at baseline. In addition, those who are immunocompromised appear to be at a higher risk of migraine-like disorders. A recent study showed that migraine caused changes to transcription of immune genes in the blood, even following treatment with sumatriptan. The dura mater is densely packed with macrophages, mast and dendritic cells, and they have been found to associate with meningeal blood vessels and trigeminal afferent endings. Recent work in mice shows activation and morphological changes of these cells in rodents following the migraine trigger cortical spreading depression. Importantly, each of these immune cell types can respond directly to CGRP. Since immune cells make up a large portion of the dura, have functional responses to CGRP, and interact with trigeminal afferents, CGRP actions on the dural immune system are likely to play key roles in migraine.

Autoimmune Vestibulopathy—A Case Series

Autoimmune inner ear disease (AIED) is a rare clinical entity. Its pathogenicity, heterogenous clinical presentation in the context of secondary systemic autoimmune disease and optimal treatment avenues remain poorly understood. Vestibular impairment occurring in the context of AIED is rarely subject to detailed investigation given that the auditory symptoms and their responsiveness to immunosuppression are the focus of the few proposed diagnostic criteria for AIED. We present three cases of vestibulopathy occurring in the context of autoimmune inner ear conditions, including the first known report of autoimmune inner ear pathology arising with a temporal association to administration of the Pfizer-BioNTech SARS-CoV2 vaccination. We review the available literature pertinent to each case and summarise the key learning points, highlighting the variable presentation of vestibular impairment in AIED.