Risk Of Migraine Research Articles

Long-term effectiveness and safety of transcatheter closure of patent foramen ovale compared with antithrombotic therapy alone: a meta-analysis of six randomised clinical trials and 3,560 patients with reconstructed time-to-event data.

Although three recent trials have shown a significant stroke risk reduction after tPFOc, the individual statistical power is limited and the impact on pooled evidence needs to be explored. We aimed to pool data from available randomised clinical trials (RCT) to assess whether tPFOc is more effective and safe than antithrombotic therapy alone (ATA). Major electronic databases and tangential sources were searched. Six trials (3,560 patients) were identified. At a median follow-up of 3.6 (2.0-5.2) years (13,930 person-years), the risk of stroke was significantly lower after tPFOc compared with ATA (HR 0.28, 95% CI: 0.12-0.64, p=0.003). Significant heterogeneity was detected (I2=66.1%), although single trials did not significantly influence the results. Reconstructed time-to-event data revealed that tPFOc benefits accrue after approximately one year and persist over time without significant variations (96.4% versus 88.0%; HR 0.25, 95% CI: 0.09-0.66, p=0.005; NNT=11). Although results showed a greater benefit in patients <45 years old, male, and with substantial shunt, interaction between subgroups was not significant. Trial sequential analysis showed that accumulated evidence appeared to be sufficient. However, tPFOc did not confer protection against transient ischaemic attack (TIA; HR 0.69, 95% CI: 0.31-1.54, p=0.365) and a significant excess in the risk of atrial fibrillation was observed (OR 4.99, 95% CI: 1.99-10.10, p<0.001), though generally early and transient. Major bleeding and migraine were comparable between treatments. Compared with ATA, tPFOc significantly reduces the risk of stroke at long-term follow-up but no benefit is observed in terms of TIA. Atrial fibrillation is higher after tPFOc, though generally early and transient. The risks of major bleeding and migraine are comparable between the groups.

Генетика мигрени: ассоциативные исследования

Статья посвящена анализу имеющихся на сегодняшний день данных генетических полиморфизмов, излучавшихся при мигрени. При мигрени гены-кандидаты мигрени сгруппированы в четыре функциональных семейства генов: гены нервной системы, гены сердечно-сосудистой системы, гормональные, воспалительные гены. Среди генов нервной системы значимость представляют гены, кодирующие структуру и функциональную активность калиевых каналов. Наибольший интерес представляют гены сердечно-сосудистой системы, которые как повышают риск мигрени, так и увеличивают риск коморбидных кардиоваскулярных заболеваний. Среди генов эндокринной системы роль в патогенезе мигрени играют полиморфизмы гена эстрогенового рецептора 1 типа. Для воспалительных генов циклооксегиназы 2, главного комплекса гистосовместимости HLA-DRB1, лимфотоксина альфа, фактора некроза опухоли альфа и бета найдены положительные ассоциации с мигренью. The article focused on analysis of currently available reports on genetic polymorphisms in migraine. The migraine candidate genes were grouped into four functional families: genes of the nervous system, genes of the cardiovascular system, hormonal genes, and inflammatory genes. Among the nervous system genes, the genes encoding the structure and functional activity of potassium channels are of a special significance. Of the greatest interest are the cardiovascular system genes, which increase the risk of both migraine and comorbid cardiovascular diseases. Among the endocrine system genes, polymorphisms of the type 1 estrogen receptor gene play a role in the pathogenesis of migraine. Positive associations with migraine were found for inflammatory genes of cyclooxygenase 2, the main histocompatibility complex HLA-DRB1, lymphotoxin alpha, and tumor necrosis factors alpha and beta.

Common variants at 5q33.1 predispose to migraine in African-American children

BackgroundGenome-wide association studies (GWASs) have identified multiple susceptibility loci for migraine in European adults. However, no large-scale genetic studies have been performed in children or African Americans with migraine.MethodsWe conducted...

Ambient air pollution exposure and risk of migraine: Synergistic effect with high temperature

BackgroundMigraine is a chronic and agonizing neurological disorder prevalent worldwide. Although its pathogenesis remains unclear, limited evidence exists on the role of air pollution. ObjectiveWe aimed to assess the association of short-term air pollution exposure with migraine in conjunction with the synergistic effect of temperature. MethodsWe identified 18,921 patients who visited emergency departments (EDs) for migraine as a primary disease in Seoul from the national emergency database between 2008 and 2014. We conducted a time-stratified, case-crossover analysis to compare levels of particles <2.5 μm (PM2.5), particles <10 μm (PM10), nitrogen dioxide (NO2), sulfur dioxide (SO2), ozone (O3), and carbon monoxide (CO) on ED visit days and those on the control days matched to day of the week, month, and year. We evaluated the synergistic effects of air pollution and temperature using an interaction term. ResultsHigher air pollution levels were significantly associated with risk of migraine over various lag structures. In the best fitting lags, the odds ratio (OR) associated with an interquartile range increase of PM2.5, PM10, NO2, O3, and CO was 1.031 (95% CI: 1.010–1.053), 1.032 (95% CI: 1.007–1.057), 1.053 (95% CI: 1.022–1.085), 1.034 (95% CI: 1.001–1.067), and 1.029 (95% CI: 1.005–1.053), respectively. The SO2 effect was positive but not significant (OR 1.019 [95% CI: 0.991–1.047]). The PM effect was significantly stronger on high-temperature days (above the 75th percentile) than on low-temperature days (PM2.5, high: OR 1.068, low: OR 1.021, Pinteract = 0.03; PM10, high: OR 1.066, low: OR 1.014, Pinteract = 0.02). ConclusionOur study provides new evidence that air pollution exposure may trigger migraine especially on high-temperature days, and this finding may contribute in establishing preventive measures against migraine.

Impact of migraine on the clinical presentation of insomnia: a population-based study

BackgroundInsomnia and migraine are closely related; insomnia aggravates migraine symptoms. This study was conducted to investigate the impact of migraine on the clinical presentation of insomnia symptoms.MethodsThe data of the Korean Headache-Sleep Study (KHSS) were used in the present study. The KHSS is a nation-wide cross-sectional population-based survey regarding headache and sleep in Korean adults aged 19 to 69 years. If a participant’s Insomnia Severity Index (ISI) score ≥ 10, she/he was classified as having insomnia. The clinical presentation of insomnia symptoms was assessed using total and subcomponent scores of the ISI.ResultsOf 2695 participants, 290 (10.8%) and 143 (5.3%) individuals were assigned as having insomnia and migraine, respectively. The proportions of migraine (12.8% vs. 4.4%, p < 0.001) and non-migraine headache (59.0% vs. 39.9%, p < 0.001) were higher among individuals with insomnia compared to those without insomnia. Among participants with insomnia, total ISI scores were not significantly different among participants with migraine, non-migraine, and non-headache [median and interquartile range: 13.0 (11.0–17.5) vs. 13.0 (11.0–17.5) vs. 12.0 (11.0–16.0), p = 0.245]. ISI scores for noticeability of sleep problems to others were significantly higher among participants with migraine [3.0 (2.0–4.0) vs. 2.0 (2.0–3.0), p = 0.011] and non-migraine headache [3.0 (2.0–4.0) vs. 2.0 (2.0–3.0), p = 0.001] compared to those without headache history. Other ISI subcomponent scores did not significantly differ between headache status groups.ConclusionsParticipants with insomnia had an increased risk of migraine and non-migraine headache compared to those without insomnia. Among participants with insomnia, overall insomnia severity was not significantly influenced by the headache status.

Association Between Migraine and Breast Cancer Risk: A Population-Based Cohort Study and Literature Review.

Objective: Previous case-control studies have suggested that women with migraine have lower risk of developing breast cancer, but conflicting results were noted in cohort studies. We investigated the association between migraine and breast cancer incidence in a nationwide population-based cohort study. Methods: We identified 25,606 women with migraine between 2000 and 2013 from the National Health Insurance Research Database in Taiwan. Each migraineur was randomly frequency matched with four women without migraine by age and index year of migraine diagnosis. Cox's proportional hazard regression analysis was performed to estimate the association between migraine on the risk of developing breast cancer. Results: With a mean follow-up of 7.3 years, 234 and 978 breast malignancies occurred in the migraine cohort and matched cohort, respectively. Migraine was not associated with the risk of breast cancer (adjusted hazard ratio = 1.03, 95% confidence interval = 0.89-1.21). Among women with migraine, independent risk factors for breast cancer included older age, alcohol-related illness, and receipt of a greater number of breast cancer screening examinations, and independent protective factors included the use of antihypertensive agents, statins, and nonsteroidal anti-inflammatory drugs. Further analyses indicated that women with ≥4 medical visits for migraine per year had a significantly greater risk of breast cancer than the matched cohort. Conclusions: Migraine was not associated with a decreased risk of developing breast cancer among Taiwanese women. Further prospective studies on other geographic populations or on the association between migraine frequency and the risk of developing breast cancer are warranted to validate our findings.

Endothelial nitric oxide synthase (−786T&gt;C) polymorphism and migraine susceptibility

Background:The aim of this study was to evaluate the correlation between endothelial nitric oxide synthase (eNOS) polymorphism (−786T>C) and migraine susceptibility in a meta-analysis.Methods:A literature search was performed for case–control studies from inception to July 30, 2018 focusing on eNOS polymorphism (−786T>C) and risk of migraine. From 454 full-text articles, 6 were included in this study. Heterogeneity was assessed with the I2 index and quality assessment was performed using the Newcastle–Ottawa scale.Results:CC genotype was not related to higher susceptibility of migraine compared with TT+ TC genotypes with significant difference (fixed effects model; OR = 1.27; 95% CI = 0.90–1.80; P = .17; I2 = 18%). However, subgroup analysis showed CC variant increase the risk for migraine compared with TT+ TC genotypes in Caucasian populations (fixed effects model; OR = 1.62; 95% CI = 1.03–2.56; P = .04; I2 = 18%), which could not be observed in non-Caucasian populations (fixed effects model; OR = 0.88; 95% CI = 0.51–1.53; P = .66; I2 = 0%). There was no significant difference for other genotypes and alleles between patients with migraine and healthy controls (all P > .05).Conclusion:This meta-analysis indicated that CC variant increases the risk for migraine compared with TT + TC genotypes in Caucasian populations.

Methylenetetrahydrofolate reductase polymorphism (MTHFR C677T) and headache in children: a retrospective study from a tertiary level outpatient service

BackgroundIn adult studies the MTHFR C677T polymorphism has been associated with an increased risk of migraine, but little research has been done in this area in children.MethodsA retrospective study of children referred with headache to a tertiary level Paediatric Neurology Service between 2008 and 2012. This study included only patients who had been genotyped for the MTHFR C677T polymorphism. An evaluation of homocysteine serum levels was necessary to exclude other types of migraine.ConclusionCompared with the wild-type genotype, the T/T genotype was associated with an increased risk of any type of migraine, though the statistical significance was greatest in migraine with aura. The homocysteine serum levels were significantly higher in migraine with aura compared to migraine without aura. In a pediatric population MTHFR T/T homozygosity influences susceptibility to migraine.

Synergism between Female Gender and High Levels of Daily Stress Associated with Migraine Headaches in Ontario, Canada

Background: Migraines affect women more than men and originate from interactions of genetic and environmental factors. This study assessed the prevalence of migraines in Ontario, Canada and the effect of gender and stress on migraines. Methods: Our analysis was based on data from 42,282 persons 12 years or older who participated in the 2013–2014 Canadian Community Health Survey. Multivariate log-binomial model was used to calculate adjusted prevalence ratios for migraines associated with individual and joint exposures of female gender and stress. We used relative excess risk due to interaction (RERI), attributable proportion (AP), and synergy index (S index) to measure additive interaction. Results: The prevalence of migraines was 10.7%. The adjusted prevalence ratios were 2.37 (95% CI 2.13–2.63) for female versus male, 1.63 (95% CI 1.39–1.90) for persons with high versus low levels of stress, and 3.38 (95% CI 3.00–3.80) for women with high stress versus men with low stress. The RERI estimate was 0.38 (95% CI 0.04–0.73), the AP estimate was 0.11 (95% CI 0.02–0.21), and the S index was 1.19 (95% CI 1.01–1.41). Conclusion: We report 10.7% prevalence of migraines and synergism between female gender and stress on risk of migraine, suggesting health interventions targeting women under stress may be beneficial.

Discovery of TRPM8 Antagonist ( S)-6-(((3-Fluoro-4-(trifluoromethoxy)phenyl)(3-fluoropyridin-2-yl)methyl)carbamoyl)nicotinic Acid (AMG 333), a Clinical Candidate for the Treatment of Migraine.

Transient-receptor-potential melastatin 8 (TRPM8), the predominant mammalian cold-temperature thermosensor, is a nonselective cation channel expressed in a subpopulation of sensory neurons in the peripheral nervous system, including nerve circuitry implicated in migraine pathogenesis: the trigeminal and pterygopalatine ganglia. Genomewide association studies have identified an association between TRPM8 and reduced risk of migraine. This disclosure focuses on medicinal-chemistry efforts to improve the druglike properties of initial leads, particularly removal of CYP3A4-induction liability and improvement of pharmacokinetic properties. A novel series of biarylmethanamide TRPM8 antagonists was developed, and a subset of leads were evaluated in preclinical toxicology studies to identify a clinical candidate with an acceptable preclinical safety profile leading to clinical candidate AMG 333, a potent and highly selective antagonist of TRPM8 that was evaluated in human clinical trials.

Do pre-school episodic syndromes predict migraine in primary school children? A retrospective cohort study on health care data.

To assess the relative risk, predictive value and population attributable risk fraction of pre-school episodic syndromes for later migraine in primary school age children. This retrospective cohort study used health insurance data on 55,035 children born in 2006 with no diagnosis of migraine up to the age of 5 years. The relative risk, probability and population attributable risk fraction of migraine prompting a physician visit at the age of 6-10 years in children with episodic syndromes included in the International Classification of Headache Disorders (benign paroxysmal torticollis, benign paroxysmal vertigo, cyclic vomiting syndrome, recurrent abdominal symptoms and abdominal migraine) and those not included in the International Classification of Headache Disorders (pavor nocturnus, somnabulism and bruxism) diagnosed up to the age of 5 years were determined. The period prevalence of individual episodic syndromes ranged between 0.01% and 1.40%. For episodic syndromes included in the International Classification of Headache Disorders (recurrent abdominal symptoms and abdominal migraine) and for the episodic syndromes not included in the International Classification of Headache Disorders (somnambulism), the risk for later migraine was increased by factors of 2.08, 21.87 and 3.93, respectively. The proportion of risk for migraine in primary school children explained by any episodic syndromes included in the International Classification of Headache Disorders was 2.18% and for any episodic syndromes not included in the International Classification of Headache Disorders it was 0.59%. Several pre-school episodic syndromes are risk factors for migraine in primary school age children. The fraction of migraine in primary school age children explained by prior episodic syndromes, however, is below 3%. A probability to develop primary school age migraine above 50% was only observed for abdominal migraine.

Sex and Gender Differences in Migraine-Evaluating Knowledge Gaps.

Migraine is a common chronic neurological disease that disproportionately affects women. Migraine has significant negative effects on physical, emotional, and social aspects of health, and can be costly for patients, employers, and society as a whole. Growing evidence supports the roles of sex and gender in migraine risk, pathophysiology, presentation, diagnosis, treatment, and management. However, sex and gender differences in migraine have received limited attention, which can impede advancements in migraine detection, treatment, care, and education. The Society for Women's Health Research convened an interdisciplinary expert panel of researchers, clinicians, and advocates for a roundtable meeting to review the current research on sex and gender differences in migraine. This review summarizes discussions from the roundtable and prioritizes areas of need that warrant further attention in migraine research, care, and education. Examining sex and gender differences in migraine and addressing knowledge gaps will decrease the health and economic burden of migraine for both women and men.

Migraine in adults with diabetes; is there an association? Results of a population-based study

AimsTo investigate the association between migraine and diabetes mellitus while controlling for several socio-demographic characteristics, comorbidities, and lifestyle variables. We also aimed to identify which of these variables are associated with migraine among diabetics.Patients and methodsWe conducted a cross-sectional study using data taken from the European Health Interview Surveys for Spain conducted in 2009/10 (n=22,188) and 2014 (n=22,842). We selected those subjects ≥40 years of age. Diabetes status was self-reported. One non-diabetic control was matched by the year of survey, age, and sex for each diabetic case. The presence of migraine was defined as the affirmative answer to both of the following questions: “Have you suffered migraine or frequent headaches over the last 12 months?” and “Has your physician confirmed the diagnosis?”. Independent variables included demographic and socio-economic characteristics, health status variables, lifestyle, and pain characteristics.ResultsThe prevalence of migraine was significantly higher among those suffering from diabetes (14.9% vs. 13.0%; p=0.021). The multivariable analysis showed that diabetes was not associated with a higher risk of migraine (adjusted OR 1.06; 95%CI 0.89–1.25). Among diabetic subjects, female sex, suffering concomitant mental disorders, respiratory disorders, neck pain, and low back pain were variables associated with suffering from migraine.ConclusionWe found no significant differences in the prevalence of migraine between diabetics and non-diabetic age- and sex-matched controls after controlling for possible confounders.

Estrogen, migraine, and vascular risk.

Migraine has a predilection for female sex and the course of symptoms is influenced by life stage (presence of menstrual cycle, pregnancy, puerperium, menopause) and use of hormone therapy, such as hormonal contraception and hormone replacement therapy. Hormonal changes figure among common migraine triggers, especially sudden estrogen drop. Moreover, estrogens can modulate neuronal excitability, through serotonin, norepinephrine, dopamine, and endorphin regulation, and they interact with the vascular endothelium of the brain. The risk of vascular disease, and ischemic stroke in particular, is increased in women with migraine with aura (MA), but the link is unclear. One hypothesis posits for a causal association: migraine may cause clinical or subclinical brain lesions following repeated episodes of cortical spreading depression (CSD) and a second hypothesis that may explain the association between migraine and vascular diseases is the presence of common risk factors and comorbidities. Estrogens can play a differential role depending on their action on healthy or damaged endothelium, their endogenous or exogenous origin, and the duration of their treatment. Moreover, platelet activity is increased in migraineurs women, and it is further stimulated by estrogens.This review article describes the course of migraine during various life stages, with a special focus on its hormonal pathogenesis and the associated risk of vascular diseases.

Coloring of the past via respondent's current psychological state, mediation, and the association between childhood disadvantage and morbidity in adulthood

ObjectiveMany researchers view retrospective reports with skepticism. Indeed, the observed association between retrospectively-reported childhood disadvantage (CD) and morbidity in adulthood has been criticized as an artefactual correlation driven by the psychological state of the respondent at the time of reporting (current psychological state). The aim of this study was to assess the role of current psychological state in the association between childhood disadvantage and morbidity in adulthood. MethodsThe present analysis used cross-sectional data collected in 2007–2008 within the framework of the Tromsø Study (N = 10,765), a representative study of adult men and women in Norway. The association between CD and the physical health outcomes heart attack, angina pectoris, chronic bronchitis/emphysema/COPD, diabetes mellitus, hypothyroid/low metabolism, migraine, hypertension, and comorbidity (i.e., the sum of these physical health outcomes) was assessed with Poisson regression models. Relative risks (RR) and 95% confidence intervals (CI) were estimated. A wide range of indicators of respondents’ current psychological state were included in the models to assess the % attenuation in estimates. ResultsCD was associated with an increased risk of heart attack, angina pectoris, chronic bronchitis/emphysema/COPD, diabetes mellitus, hypothyroid/low metabolism, migraine, hypertension, and comorbidity (p < 0.05), independent of respondents' current psychological state. A sizeable proportion (23–42%) of the association between CD and physical health outcomes was driven by recall bias or mediation via respondents’ current psychological state. Controlling for indicators of current psychological state reduced the strength of associations between CD and physical health outcomes; however, the independent associations remained in the same direction. ConclusionThe association between retrospectively-reported CD and physical health outcomes in adulthood is not driven entirely by respondent's current psychological state.

Harm avoidance and depression, anxiety, insomnia, and migraine in fifth-year medical students in Taiwan.

PurposeDuring medical school training, increased stress, depression, and anxiety are common. Certain personality traits, particularly harm avoidance (HA), may increase the risk of psycho-pathological disorders, insomnia, and migraine among medical students. This study evaluated the role HA may play on levels of stress, depression, anxiety, and insomnia among Taiwanese medical students starting their fifth and final year of medical school.Patients and methodsA series of self-report questionnaires were used to measure the severity of anxiety, depression, and insomnia, as well as somatic symptoms, particularly migraine headache, among 143 Taiwanese fifth-year medical students (94 males and 49 females). Most had normal or mild levels of anxiety, depression, insomnia, and migraine.ResultsHA personality trait was significantly associated with depression (all P ≤ 0.001) after adjusting for other factors. HA was not significantly associated with anxiety, insomnia, or migraine headache days.ConclusionHA personality trait was significantly associated with depression among fifth-year medical students in Taiwan.

The NRP1 migraine risk variant shows evidence of association with menstrual migraine

BackgroundIn 2016, a large meta-analysis brought the number of susceptibility loci for migraine to 38. While sub-type analysis for migraine without aura (MO) and migraine with aura (MA) found some loci showed specificity to MO, the study did not test the loci with respect to other subtypes of migraine. This study aimed to test the hypothesis that single nucleotide polymorphisms (SNPs) robustly associated with migraine are individually or collectively associated with menstrual migraine (MM).MethodsGenotyping of migraine susceptibility SNPs was conducted using the Agena MassARRAY platform on DNA samples from 235 women diagnosed with menstrual migraine as per International Classification for Headache Disorders II (ICHD-II) criteria and 140 controls. Alternative genotyping methods including restriction fragment length polymorphism, pyrosequencing and Sanger sequencing were used for validation. Statistical analysis was performed using PLINK and SPSS.ResultsGenotypes of 34 SNPs were obtained and investigated for their potential association with menstrual migraine. Of these SNPs, rs2506142 located near the neuropilin 1 gene (NRP1), was found to be significantly associated with menstrual migraine (p = 0.003). Genomic risk scores were calculated for all 34 SNPs as well as a subset of 7 SNPs that were nearing individual significance. Overall, this analysis suggested these SNPs to be weakly predictive of MM, but of no prognostic or diagnostic value.ConclusionsOur results suggest that NRP1 may be important in the etiology of MM. It also suggests some genetic commonality between common migraine subtypes (MA and MO) and MM. The identification of associated SNPs may be the starting point to a better understanding of how genetic factors may contribute to the menstrual migraine sub-type.

The association between obesity and migraine in a population of Iranian adults: a case-control study

AimTo assess the association between obesity and risk of migraine with aura and features of migraine attacks among a population of Iranian adults. MethodsIn this case-control study, 102 confirmed cases of migraine with aura were matched based on age and gender with 102 healthy subjects. Data on demographic characteristics and anthropometric measurements were collected from all cases and controls by the same methods. Overweight and obesity were considered as body mass index ≥25–30 kg/m2 and ≥ 30 kg/m2, respectively. Features of migraine attacks including frequency, duration and headache daily result were determined for patients based on international headache society criteria. ResultsMean age of subjects was 34.5 ± 7.4 years and 77.9% of them were female. Compared with subjects with normal body mass index, those with obesity had greater odds for having migraine with aura (OR: 3.06, 95% CI: 1.11–8.43). Such finding was also seen even after adjusting for confounding variables; in a way that subjects with obesity were 2.92 times more likely for having migraine with aura compared with those with normal weight (OR: 2.92, 95% CI: 1.03-8.33). Among migraine with aura patients, we found that those with obesity had higher headache daily result compared with subjects with normal weight. However, obesity was not associated with frequency and duration of migraine attacks. ConclusionsWe found that obesity was positively associated with risk of migraine with aura. In addition, subjects with obesity had higher headache daily result compared with those with normal weight.

Association of expression of DRD2 rs1800497 polymorphism with migraine risk in Han Chinese individuals.

BackgroundPrevious studies suggested that single-nucleotide polymorphisms in dopamine receptor D2 (DRD2) are the susceptibility loci for migraine. This study was aimed at evaluating the contribution of DRD2 rs1800497 and its expression to migraine risk in Han Chinese subjects.MethodsIn total, 250 patients with migraine and 250 age- and sex-matched control subjects were included in this study. TaqMan allelic discrimination assay was used for DRD2 rs1800497 genotyping. Plasma DRD2 concentration was determined using enzyme-linked immunosorbent assay.ResultsSignificant associations were observed for the rs1800497 genotype (c2=6.37, p=0.041) and allele (c2=4.69, p=0.03; odds ratio [OR]=1.33, 95% CI=1.03–1.72, power=58%) frequencies between the migraine and control groups. Sex analysis indicated a positive association for rs1800497 between female patients with migraine and control individuals (genotype: c2=7.84, p=0.019; allele: c2=6.60, p=0.010; OR=1.61, 95% CI=1.12–2.30, power=73.4%). Furthermore, a significant association was observed only in female patients with migraine without aura (MO) (genotype: c2=6.88, p=0.032; allele: c2=5.65, p=0.017; OR=1.59, 95% CI=1.08–2.36, power=65.1%). The mean plasma DRD2 levels in the control group (mean±SD: 24.20±2.78) were significantly lower than those in the migraine with aura (MA) (30.86±3.69, p<0.0001) and MO groups (31.88±4.99, p<0.0001). Additionally, there was a sex-based difference in DRD2 expression in the MA (male vs female: 29.46±3.59 vs 32.27±3.27, p<0.01) and MO groups (male vs female: 29.18±3.50 vs 34.58±4.84, p<0.0001). Moreover, plasma DRD2 levels in patients were significantly different among the three genotypes (CC vs CT vs TT: 24.76±3.76 vs 30.93±3.85 vs 37.06±3.95, p<0.0001). Similar results were observed both in the MA (CC vs CT vs TT: 25.09±3.84 vs 28.57±2.84 vs 33.37±1.58, p<0.0001) and MO groups (CC vs CT vs TT: 24.65±3.79 vs 31.65±3.86 vs 38.29±3.74, p<0.0001).ConclusionOur case–control study suggested that the DRD2 polymorphism rs1800497 was significantly associated with the risk of migraine in Han Chinese females. Additionally, the plasma DRD2 level was high in patients with migraine. Females with migraine had considerably higher DRD2 levels than males with migraine. DRD2 expression may be regulated by DRD2 rs1800497 genotype in patients with migraine.

Association between Cervical Spondylosis and Migraine: A Nationwide Retrospective Cohort Study.

Background: Few studies have investigated the longitudinal association between cervical spondylosis (CS) and migraine by using a nationwide population-based database. Methods: We conducted a retrospective cohort study from 2000 to 2011 identifying 27,930 cases of cervical spondylosis and 111,720 control subjects (those without cervical spondylosis) from a single database. The subjects were frequency-matched on the basis of sex, age, and diagnosis date. The non- cervical spondylosis cohort was four times the size of the cervical spondylosis cohort. To quantify the effects of cervical spondylosis on the risk of migraine, univariate and multivariate Cox proportional hazard regression analyses were used to calculate the hazard ratio (HR), and 95% confidence interval (CI). Results: After a 10-year follow-up controlling for potential confounding factors, overall migraine incidence was higher in the cervical spondylosis cohort than in the non-cervical spondylosis cohort (5.16 and 2.09 per 1000 people per year, respectively; crude hazard ratio = 2.48, 95% confidence interval = 2.28–2.69), with an adjusted hazard ratio of 2.03 (95% confidence interval = 1.86–2.22) after accounting for sex, age, comorbidities, and medication. Individuals with myelopathy in the cervical spondylosis cohort had a 2.19 times (95% confidence interval = 1.80–2.66) higher incidence of migraine when compared than did those in the non- cervical spondylosis cohort. Conclusions: Individuals with cervical spondylosis exhibited a higher risk of migraine than those without cervical spondylosis. The migraine incidence rate was even higher among individuals with cervical spondylotic myelopathy.