The Role of Vitamin D in Primary Headache-from Potential Mechanism to Treatment

New evidence that vitamin D prevents headache: a bidirectional two-sample Mendelian randomization analysis

Background

Previous observational clinical studies and meta-analyses have yielded inconsistent results regarding the relationship between vitamin D and headache, and the causal relationship remains unclear. The aim of this study was to investigate the causal relationship between vitamin D and headache by bidirectional two-sample Mendelian randomisation (MR) analysis.

Methods

The relationship between high levels of vitamin D and headache was investigated by two-sample MR analysis using publicly available genome-wide association study (GWAS) data. The primary method was inverse variance weighting (IVW), and secondary methods were weighted median and MR-Egger methods. No heterogeneity or horizontal multidirectionality was found in the MR results. The robustness and validity of the findings were assessed using the leave-behind method.

Results

A significant causal relationship was found between high vitamin D levels and headache using the IVW method (OR = 0.848; p = 0.007; 95% CI = 0.752-0.956). However, in a reverse analysis, no evidence of a causal relationship between headache and high levels of vitamin D was found using the IVW method (OR = 1.001; p = 0.906; 95% CI = 0.994-1.006). Our MR analyses showed no significant horizontal multidimensionality or heterogeneity (p > 0.05). Sensitivity analyses confirmed that MR estimates were not affected by single nucleotide polymorphisms (SNPs). Confirmation that our results are robust and valid has been obtained by the leave-one-out method.

Conclusion

Our study suggests that high levels of vitamin D prevent the risk of headache. However, there is no evidence of a causal relationship between headache and high levels of vitamin D. Vitamin D may reduce the risk of headache.

Recent advances in diagnosing, managing, and understanding the pathophysiology of cluster headache

Cluster headache, characterised by attacks of severe, recurrent, unilateral headache and ipsilateral cranial autonomic symptoms, remains a primary headache with an elusive pathophysiology. Recent advances have introduced effective treatments and broadened understanding of the clinical features of cluster headache. These features are similar in patients globally, but regional differences in prevalence and burden exist. International collaborations have led to identification of eight genetic loci associated with cluster headache. The pathophysiological mechanisms are still not fully understood but recent studies show that targeting the trigeminal autonomic reflex by neurostimulation, or targeting the neuropeptide calcitonin gene-related peptide (CGRP), might lessen the attack burden. The US Food and Drug Administration has approved galcanezumab, a monoclonal antibody targeting CGRP, as the first specific preventive treatment for episodic cluster headache. However, a preventive effect was not replicated in chronic cluster headache, and the European Medicines Agency did not approve galcanezumab, restricting its availability in Europe. Owing to the low prevalence of cluster headache, continued collaboration through multicentre clinical trials and data sharing will be imperative for further breakthroughs in understanding and management.

Neurasites®-A Standardized Plant Extract in the Treatment and Prevention of Migraine Attacks

Background/Objectives: Migraine is one of the most common diseases in highly developed countries, being even more common than diabetes and asthma. Migraines can affect emotional, social, and physical wellbeing as well as professional life. The most common symptoms are severe headaches associated with nausea, vomiting, photophobia and sonophobia, difficulty concentrating, sensitivity and emotional disorders. Many studies have been published to establish the best migraine-management drugs, but not many of them refer to plant extracts, which have been given more attention by patients lately. Among these generically called herbal medicines, the effect of tussilago hybrida standardized extract has been studied since the early twenties. This stands as the fundamental component of Neurasites® and the reason for research on materials and methods, results on treatment schemes for diminishing migraine attack features, as well as migraine prevention. Methods: There are two directions of research (herbal and placebo medicine) considered to be of interest due to the actual trend toward natural medicine and against chemicals and associated drugs. For quantitative research, the research tool used was that of the Neurasites® Questionnaire Survey (NQS). Results: The obtained results prove the efficacy of treatment by reducing the duration of headache attacks, diminishing pain intensity and decreasing the frequency of migraine episodes. Conclusions: Further research development should focus on other dosages and treatment schemes and on other similar natural products to be used in migraine attack treatment.

Nutrient insufficiencies and deficiencies involved in the pathogenesis of bruxism (Review)

Stress has been well-documented to have a significant role in the etiopathogenesis of bruxism. Activation of the hypothalamic-pituitary-adrenal axis (HPA) and subsequent release of corticosteroids lead to increased muscle activity. Neurological studies have demonstrated that chronic stress exposure induces neurodegeneration of important neuronal structures and destabilization of the mesocortical dopaminergic pathway. These disruptions impair the abilities to counteract the overactivity of the HPA axis and disinhibit involuntary muscle activity, while at the same time, there is activation of the amygdala. Recent evidence shows that overactivation of the amygdala under stressful stimuli causes rhythmic jaw muscle activity by over activating the mesencephalic and motor trigeminal nuclei. The present review aimed to discuss the negative effects of certain vitamin and mineral deficiencies, such as vitamin D, magnesium, and omega-3 fatty acids, on the central nervous system. It provides evidence on how such insufficiencies may increase stress sensitivity and neuromuscular excitability and thereby reduce the ability to effectively respond to the overactivation of the sympathetic nervous system, and also how stress can in turn lead to these insufficiencies. Finally, the positive effects of individualized supplementation are discussed in the context of diminishing anxiety and oxidative stress, neuroprotection and in the reversal of neurodegeneration, and also in alleviating/reducing neuromuscular symptoms.

Using Machine Learning to Identify the Relationships between Demographic, Biochemical, and Lifestyle Parameters and Plasma Vitamin D Concentration in Healthy Premenopausal Chinese Women

INTRODUCTION

Vitamin D plays a vital role in maintaining homeostasis and enhancing the absorption of calcium, an essential component for strengthening bones and preventing osteoporosis. There are many factors known to relate to plasma vitamin D concentration (PVDC). However, most of these studies were performed with traditional statistical methods. Nowadays, machine learning methods (Mach-L) have become new tools in medical research. In the present study, we used four Mach-L methods to explore the relationships between PVDC and demographic, biochemical, and lifestyle factors in a group of healthy premenopausal Chinese women. Our goals were as follows: (1) to evaluate and compare the predictive accuracy of Mach-L and MLR, and (2) to establish a hierarchy of the significance of the aforementioned factors related to PVDC.

METHODS

Five hundred ninety-three healthy Chinese women were enrolled. In total, there were 35 variables recorded, including demographic, biochemical, and lifestyle information. The dependent variable was 25-OH vitamin D (PVDC), and all other variables were the independent variables. Multiple linear regression (MLR) was regarded as the benchmark for comparison. Four Mach-L methods were applied (random forest (RF), stochastic gradient boosting (SGB), extreme gradient boosting (XGBoost), and elastic net). Each method would produce several estimation errors. The smaller these errors were, the better the model was.

RESULTS

Pearson's correlation, age, glycated hemoglobin, HDL-cholesterol, LDL-cholesterol, and hemoglobin were positively correlated to PVDC, whereas eGFR was negatively correlated to PVDC. The Mach-L methods yielded smaller estimation errors for all five parameters, which indicated that they were better methods than the MLR model. After averaging the importance percentage from the four Mach-L methods, a rank of importance could be obtained. Age was the most important factor, followed by plasma insulin level, TSH, spouse status, LDH, and ALP.

CONCLUSIONS

In a healthy Chinese premenopausal cohort using four different Mach-L methods, age was found to be the most important factor related to PVDC, followed by plasma insulin level, TSH, spouse status, LDH, and ALP.

Low Vitamin D Levels Are Associated With Long COVID Syndrome in COVID-19 Survivors

CONTEXT

Long COVID is an emerging syndrome affecting 50% to 70% of COVID-19 survivors that still lacks predicting factors.

OBJECTIVE

Due to the extraskeletal effects of vitamin D, we retrospectively assessed the association between 25(OH) vitamin D levels and long COVID in COVID-19 survivors 6 months after hospitalization.

METHODS

Long COVID was defined according to NICE guidelines. Fifty long COVID and 50 non-long-COVID subjects matched on a 1:1 basis were enrolled from an outpatient clinic post-COVID cohort seen from August to November 2020. Therapies/comorbidities affecting calcium/vitamin D/bone metabolism, and/or admission to the intensive care unit during hospitalization were exclusion criteria. 25(OH) Vitamin D was measured at hospital admission and 6 months after discharge.

RESULTS

We observed lower 25(OH) vitamin D levels, evaluated at follow-up, in subjects with long COVID than those without (20.1 vs 23.2 ng/mL, P = .03). Regarding the affected health areas evaluated in the entire cohort, we observed lower 25(OH) vitamin D levels in those with neurocognitive symptoms at follow-up (n = 7) than those without (n = 93) (14.6 vs 20.6 ng/mL, P = .042). In patients presenting vitamin D deficiency (<20 ng/mL), both at admission and at follow-up (n = 42), those affected by long COVID (n = 22) presented lower 25(OH) vitamin D levels at follow-up than those not affected (n = 20) (12.7 vs 15.2 ng/mL, P = .041). In multiple regression analyses, lower 25(OH) vitamin D levels at follow-up were the only variable significantly associated with long COVID in our cohort (P = .008, OR 1.09, CI 1.01-1.16).

CONCLUSION

COVID-19 survivors with long COVID have lower 25(OH) vitamin D levels than matched patients without long COVID. Our data suggest that vitamin D levels should be evaluated in COVID-19 patients after hospital discharge. The role of vitamin D supplementation as a preventive strategy of COVID-19 sequelae should be tested in randomized controlled trials.

Genetic Variability in Vitamin D Receptor and Migraine Susceptibility: A Southeastern European Case-Control Study

Migraine is a common primary headache disorder with both environmental and genetic inputs. Cumulative evidence indicates an association between vitamin D and headache. Unravelling the precise role of vitamin D and its receptor in the pathophysiology of migraine can eventually contribute to more efficient prevention and management of this headache disorder. The aim of the study was to investigate the relation of the three most studied VDR variants, i.e., FokI (rs2228570), TaqI (rs731236) and BsmI (rs1544410), with migraine susceptibility and distinct clinical phenotypes in a Southeastern European case-control population residing in Greece. DNA was extracted from 191 unrelated patients diagnosed with migraine and 265 headache-free controls and genotyped using real-time PCR (LightSNiP assays) followed by melting curve analysis. Genotype frequency distribution analysis of the TaqI and BsmI variants showed a statistically significant difference between migraine cases and controls. In addition, subgroup analyses revealed a significant association between all three studied VDR variants, particularly with a migraine without aura subtype. Therefore, the current study provides supporting evidence for a possible association of VDR variants with migraines, particularly migraine without aura susceptibility in Southeastern Europeans residing in Greece, further reinforcing the emerging role of vitamin D and its receptor in migraines.

Effects of eight weeks of aerobic exercise and vitamin D supplementation on psychiatric comorbidities in men with migraine and vitamin D insufficiency: A randomized controlled clinical trial

BACKGROUND

High prevalence of psychiatric comorbidities associated with migraine increases the risk of evolution from episodic migraine to chronic migraine. This study investigated the effects of eight weeks of aerobic exercise and vitamin D supplementation on psychiatric comorbidities in men with migraine and vitamin D insufficiency.

METHODS

Forty-eight participants took part in this randomized controlled clinical trial and were allocated into four groups: aerobic exercise and vitamin D (AE + VD), aerobic exercise and placebo (AE + Placebo), vitamin D (VD), and Placebo. AE + VD and AE + Placebo groups performed three aerobic exercise sessions per week for eight weeks and received a vitamin D supplement and placebo, respectively. The VD group received a vitamin D supplement, and the Placebo group received a placebo for eight weeks. The depression severity, quality of sleep, and physical self-concept were measured at baseline and after eight weeks.

RESULTS

The results showed that depression severity was significantly lower in AE + VD compared to AE + Placebo, VD, and Placebo at the post-test. Our results demonstrated that in the post-test, the mean score of sleep quality in AE + VD was significantly lower than AE + Placebo, VD, and Placebo. Finally, the results revealed that after eight weeks of intervention, the physical self-concept in AE + VD was significantly higher than in VD and Placebo groups.

LIMITATIONS

Not having complete control of sun exposure and the diet were the limitations.

CONCLUSION

The results indicated that the concomitant application of AE and VD supplementation could provoke synergistic effects leading to additional psycho-cognitive health benefits in men with migraine and vitamin D insufficiency.

Investigating Vitamin D Receptor Genetic Markers in a Cluster Headache Meta-Analysis

Patients diagnosed with the primary headache disorder known as cluster headache (CH) commonly report that their headache attacks occur in patterns of both circadian and seasonal rhythmicity. Vitamin D is essential for a variety of bodily functions and vitamin D levels are largely regulated by daylight exposure in connection with seasonal variation. For this Sweden-based study, the association between CH and three single-nucleotide polymorphisms in the vitamin D receptor gene, rs2228570, rs1544410, and rs731236, were investigated, as well as CH bouts and trigger factors in relation to seasonal and weather changes. Over 600 study participants with CH and 600 controls were genotyped for rs2228570, and genotyping results for rs1544410 and rs731236 were obtained from a previous genome-wide association study. The genotyping results were combined in a meta-analysis, with data from a Greek study. No significant association was found between rs2228570 and CH or the CH subtype in Sweden, nor did the meta-analysis show significant results for any of the three markers. The most common period of the year to experience CH bouts in Sweden was autumn, and conditions linked to weather or weather changes were also identified as potential triggers for CH bouts for a quarter of the responders who reported bout triggers. Though we cannot rule out vitamin D involvement in CH, this study does not indicate any connection between CH and the three vitamin D receptor gene markers.

Vitamin D metabolites and analytical challenges

Vitamin D is an essential micronutrient for bone health and the general cellular functions of the body. Its insufficiency/deficiency leads to the pathophysiology of disorders like diabetes, cancer, autoimmune, neurodegenerative, and cardiovascular diseases. Clinical interest in Vitamin D metabolites and their role in various medical disorders have contributed to an increase in laboratory demands for vitamin D measurements. For clinical and research laboratories worldwide, analysis of vitamin D and associated metabolites is a significant problem. The best way for determining vitamin D levels is constantly being debated. Various methods such as immunoassays and chromatographic techniques are available for determining vitamin D levels. Additionally, biosensors have recently been considered promising options for routine vitamin D analysis. The existing methods and other developments in the measurement of vitamin D metabolites and associated analytical challenges are discussed in this review.

Hematologic Differences Between Migraineurs and Tension-Type Headache Patients

Background

Headaches are among the most common complaints observed in neurology and medicine, notably migraines and tension-type headaches (TTH).

Objective

The purpose of this study was to compare hematologic parameters comprised hemoglobin, hematocrit, platelets, leukocytes, neutrophil-to-lymphocyte ratio (NLR), platelets-to-lymphocyte ratio (PLR) and lymphocyte-to-monocyte ratio (LMR) between migraineurs and tension-type headache patients.

Methods

This cross-sectional study included 23 migraineurs and 23 TTH-diagnosed patients, in accordance with the International Classification of Headache Disorders-3 beta version (ICHD-3-beta). The patients underwent hematological laboratory testing, which included assessments of their serum levels of hemoglobin, hematocrit, platelets, leucocytes as well as neutrophils, lymphocytes and monocytes.

Results

There were significant differences in the mean platelets serum levels between migraineurs and TTH patients, with migraineurs having 355.3 x 103/μl (SD±47.4 x 103/μl) and TTH patients having 282.0 x 103 /μl (SD± 44.2 x 103) /μl, respectively (p = 0.001). However, there were no differences in the mean level of hemoglobin, hematocrit and leukocytes between the two groups. There was also a significant difference in PLR between migraineurs and TTH patients, with a ratio of 138.1 (SD±36.0) in migraineurs and 110.2 (SD±21.9) in TTH patients (p =0.003), but no differences in NLR or LMR.

Conclusion

The mean serum levels of platelets and platelets-to-lymphocyte ratio of migraineurs were significantly higher than TTH patients. However, there were no differences in the mean levels of hemoglobin, hematocrit, leukocytes, NLR and LMR between the two groups.

Vitamin D Deficiency Association with Comorbid Diseases in Palestine: "A Cross-Sectional Observation Study"

BACKGROUND

Vitamin D deficiency (VDD) is a global health concern. This study aimed to determine the prevalence of vitamin D deficiency and its associated comorbidities in Palestine, such as diabetes mellitus, hypertension, hyperlipidemia, and cardiovascular and autoimmune diseases.

METHODS

A retrospective, descriptive study retrieved medical data from the Nat Health insurance processor database from 2014 to 2020. Patient information included age, sex, vitamin D laboratory order, symptoms, and comorbidities. This study included patients prescribed vitamin D at a dose of 50000IU for vitamin D deficiency confirmed by a serum vitamin D laboratory test. The collected data were analyzed using IBM SPSS. In addition, a chi-square test was conducted to assess the association between vitamin D deficiency, symptoms, and comorbidities.

RESULTS

Data of 3011 patients were collected; 639 patients were diagnosed with osteoporosis, and 39 patients prescribed vitamin D without a laboratory test were excluded. Approximately, 1837 (78%) participants had vitamin D deficiency. A total of 1330 women (81.3%) were significantly more likely to have vitamin D deficiency than males, 507 (72.7%; P < 0.001). Joint pain, back pain, and cervicalgia were significantly associated with vitamin D deficiency (P < 0.001). Asymptomatic participants (2.1%) were significantly less likely to have vitamin D deficiency than symptomatic participants (9.5%, p < 0.001). Hypothyroidism is significantly associated with vitamin D deficiency (p = 0.048).

CONCLUSION

In this retrospective study, the prevalence of vitamin D was high and alarming. There was a significant association between VDD, patients who presented with back pain, arthritis, and cervicalgia symptoms, and patients diagnosed with hypothyroidism. Therefore, health initiative programs are warranted to increase awareness regarding screening, prevention, and treatment. Further studies are needed to confirm the relationship between vitamin D supplementation and the reduced risk of comorbid diseases.

Pharmaceutical care for patients with headache

INTRODUCTION

Headache cephalalgia is the condition in which individuals feel pain in different parts of the head. It is one of the most common disorders believed to be amenable to self-treatment. The pharmacist can provide significant support to patients.

Higher Circulating Vitamin D Levels Are Associated With Decreased Migraine Risk: A Mendelian Randomization Study

Background

Evidence showed the supplementation of vitamin D might have beneficial effects for migraine patients. We aimed to investigate the causal effects of serum vitamin D levels on migraine risk using two-sample Mendelian randomization (MR) method.

Methods

A total of 184 independent genetic instruments for serum vitamin D levels were selected from a study in 417,580 Europeans from UK biobank. Six variants from an independent study were obtained to perform replication analysis. Summary-level data for migraine were obtained from three studies with 48,975 migraine cases, 28,852 migraine cases and 10,536 migraine cases, respectively.

Results

The estimated odds ratios (ORs) per standard deviation increase in circulating vitamin D levels based on the three migraine datasets were 0.948 (95% CI = 0.883-1.016, p = 0.133), 0.902 (95% confidence intervals [CI] = 0.825-0.986, p = 0.023), and 0.880 (95% CI = 0.786-0.984, p = 0.025), respectively. Using pooled migraine summary data with no sample overlap, MR analysis showed per standard deviation increase in circulating vitamin D levels was significantly associated with a decreased migraine risk (OR = 0.916, 95% CI = 0.859-0.977, p = 0.008). Multivariable MR analyses, sensitivity analyses and replication analysis confirmed the association. MR analyses showed similar estimates for migraine with aura and migraine without aura but with wider 95% CIs. Mediation analysis showed the effect of vitamin D on migraine risk via pathway of serum calcium was corresponding to an OR of 1.003 (95% CI = 1.001-1.005) and a proportion mediated of 3.42%. The reverse MR analysis showed migraine might not affect vitamin D levels.

Conclusion

This two-sample MR study showed genetically determined increased circulating vitamin D levels are associated with decreased migraine risk. The effect seems consistent across different migraine subtypes. In addition, the role of serum calcium in mediating the association between vitamin D and migraine is negligible. Future large well-designed randomized trials are warranted to assess the effects of vitamin D supplementation for migraine patients, especially in those with vitamin D deficiency.

The Vitamin D Role in Preventing Primary Headache in Adult and Pediatric Population

Headache is among the main neurological disorders with a great impact on both adults and children. The diagnosis of primary headache and proper management is often delayed with a great impact on work productivity and overall quality of life. Chronic headache often requires prophylactic therapy to reduce the frequency and severity of the attacks and the use of abortive medications. Besides the use of several classes of drugs, another treatment modality is the use of Nutraceuticals. Some studies have suggested a possible role of vitamin D in headache prophylaxis. Indeed, vitamin D is involved in several pathways of brain development, neuroprotection and neurotransmission. Moreover, there is data suggesting a close relationship between primary headache and vitamin D deficiency, both in children and in adults. To date, a few studies have evaluated the effect of vitamin D on headaches. The aim of this review is to summarize the data collected on headache prophylaxis with vitamin D comparing the effects of vitamin D in pediatric and adult populations.

Association Between Migraine Complicated With Restless Legs Syndrome and Vitamin D

Background: This study aimed to evaluate the prevalence of restless legs syndrome (RLS) in patients with migraine and explore its association with vitamin D deficiency, aiming to provide biological support for the comorbidity of migraine with RLS, and shed new lights into clinical diagnosis and treatment.

Methods: A case-control study was performed on 175 migraine patients and 151 non-headache controls. The information of all subjects concerning headache severity [visual analog scale (VAS) score], RLS, RLS severity [International Restless Legs Scale (IRLS) score], sleep quality [Pittsburgh sleep quality index (PSQI)], anxiety and depression symptoms [hospital anxiety and depression scale (HADS)], and demographic data were collected. At the same time, serum 25-(OH) D levels were also measured (concentration <20 ng/ml was defined deficiency). Afterward, the logistic regression model was adopted to explore the risk factors for RLS in patients with migraines.

Results: Compared with control group, migraine group had lower vitamin D levels [(21.10 ± 6.58) vs. (16.42 ± 5.6) ng/ml, P < 0.001], a higher rate of vitamin D deficiency (45.03 vs. 72%, P <0001), higher prevalence of RLS (6.62 vs. 22.29%, P < 0.001). Compared with the pure RLS group, RLS with the migraine group had lower vitamin D levels and higher IRLS score (P < 0.05). Compared with pure migraine group, migraine with RLS group had lower vitamin D levels [(17.36 ± 5.56) vs. (13.15 ± 4.42) ng/ml, P < 0.001], higher incidence of vitamin D deficiency (66.18 vs. 92.31%, P = 0.001), higher frequency of headache attacks (P = 0.004). Thereafter, the multivariate logistic regression model was employed to adjust confounding factors such as age, gender, season, frequency of headache attacks, PSQI score, and HADS scores. According to the results vitamin D deficiency in patients with migraines was an independent risk factor for RLS (OR = 5.03, 95%CI: 1.2–21.16, P = 0.027).

Conclusions: The prevalence of RLS in migraine patients was significantly higher than that in the non-headache population. Besides, vitamin D levels decreased, while the incidence of vitamin D deficiency increased in the migraine patients complicated with RLS. Finally, the occurrence of RLS in migraine patients was significantly related to vitamin D deficiency.

Headache as a Symptom of COVID-19: Narrative Review of 1-Year Research

PURPOSE OF REVIEW

Headache is a common symptom of COVID-19 with emerging literature being published on the subject. Although it may seem unspecific, scientific evidence has allowed a better definition of this headache type, revealing relevant associations with other COVID-19 symptoms and prognoses. We therefore sought to highlight the most remarkable findings concerning headache secondary to COVID-19, specifically focusing on epidemiology, characteristics, pathophysiology, and treatments.

RECENT FINDINGS

The real prevalence of headache as a symptom of COVID-19 is still unclear ranging from 10 to 70%. Headache mainly has a tension-type-like phenotype, although 25% of individuals present with migraine-like features that also occur in patients without personal migraine history. This finding suggests that a likely pathophysiological mechanism is the activation of the trigeminovascular system. SARS-CoV-2 neurotropism can occur by trans-synaptic invasion through the olfactory route from the nasal cavity, leading to anosmia which has been associated with headache. SARS-CoV-2 protein has been found not only in olfactory mucosa and bulbs but also in trigeminal branches and the trigeminal ganglion, supporting this hypothesis. However, other mechanisms such as brain vessels inflammation due to SARS-CoV-2 damage to the endothelium or systemic inflammation in the context of cytokine storm cannot be ruled out. Interestingly, headache has been associated with lower COVID-19 mortality. No specific treatment for COVID-19 headache is available at present. Studies show that investigating COVID-19 headache represents an opportunity not only to better understand COVID-19 in general but also to advance in the knowledge of both secondary and primary headaches. Future research is therefore warranted.

VDR Gene Polymorphisms and Cluster Headache Susceptibility: Case-Control Study in a Southeastern European Caucasian Population

Cluster headache (CH) is a severe primary headache disorder with a genetic component, as indicated by family and twin studies. Diurnal and seasonal rhythmicity are key features of the disease and might be related to vitamin D, as low vitamin D levels have been observed in patients with cluster headache. In addition, the vitamin D receptor (VDR) occurs in brain areas and particularly in the hypothalamus. The aim of the present case-control study was to investigate the association of cluster headache susceptibility and clinical phenotypes with the VDR gene polymorphisms FokI, BsmI and TaqI in a Southeastern European Caucasian population. DNA was extracted from 131 unrelated CH patients and 282 non-headache controls and genotyped using real-time PCR (melting curve analysis). Linkage disequilibrium (LD) analysis confirmed that BsmI and TaqI, both located in the 3'UTR of the VDR gene, are in strong LD. Genotype and allele frequency distribution analysis of the VDR FokI, BsmI, and TaqI polymorphisms showed no statistically significant difference between cases and controls, whereas haplotype analysis indicated that the TAC haplotype might be associated with decreased cluster headache susceptibility. Intra-patient analysis according to diverse clinical phenotypes showed an association of the BsmI GG and TaqI TT genotypes with more frequent occurrence of CH attacks in this cohort. Therefore, a possible association was observed between VDR gene polymorphisms BsmI and TaqI or a linked locus and susceptibility for cluster headache development and altered clinical phenotypes in the Southeastern European Caucasian study population. Further large-scale replication studies are needed to validate these findings.

Candidate Genes and Proteomic Biomarkers of Serum and Urine in Medication-Overuse Headache

Chronic headache is a topical problem of neurology, psychiatry and general practice. The medication-overuse headache (MOH) is one of the leading pathologies in the structure of chronic headache. However, early diagnosis of the MOH is challenging. We analyzed potential proteomic biomarkers of serum and urine in patients with MOH.

METHODS

We searched PubMed, Springer, Scopus, Web of Science, ClinicalKey, and Google Scholar databases for English publications over the past 10 years using keywords and their combinations.

RESULTS

We found and analyzed seven studies that met the search criteria for the purpose of the review, including 24 serum proteomic biomarkers and 25 urine proteomic biomarkers of MOH. Moreover, the candidate genes and locus of the studied serum (vitamin D-binding protein, lipocalin-type prostaglandin D2 synthase, apolipoprotein E, etc.) and urine proteomic biomarkers (uromodulin, alpha-1-microglobulin, zinc-alpha-2-glycoprotein, etc.) of MOH are presented in this review.

CONCLUSIONS

The serum and urine proteomic biomarkers of MOH can potentially help with the identification of patients with MOH development. Due to the relevance of the problem, the authors believe that further investigation of the MOH proteomic biomarkers in different ethnic and racial groups of patients with primary headache is necessary. In addition, it is important to investigate whether medications of different drug classes influence the levels of serum and urine proteomic biomarkers.

The role of vitamin D in subjective tinnitus-A case-control study

Regarding the high prevalence of vitamin D (25(OH)D) deficiency in the population and its possible association with ear diseases, we aimed to investigate the 25(OH)Dserum level in patients with subjective, nonpulsating tinnitus and its effect on tinnitus severity. The study included 201 tinnitus patients and 99 controls. Patient clinical information, including tinnitus characteristics and severity according to Tinnitus Handicap Inventory (THI), loudness assessed by Visual Analogue Scale (VAS), audiometry, and the blood level of vitamin D, was recorded. The level of 25(OH)D in tinnitus patients was significantly decreased compared with the controls (19.86 ± 7.53 and 27.43 ± 8.85 ng/ml, respectively; P value < 0.0001). More patients in the tinnitus group were deficient in vitamin D, compared with the controls (50.7% vs. 22.2% respectively, p < 0.0001). Tinnitus patients with a lower serum level of 25(OH)D (≤15 ng/dl) were significantly younger, had a higher degree of tinnitus severity measured with THI and VAS scales, had higher triglyceride and TSH levels, and a lower HDL level compared with individuals who had higher 25(OH)D level (>15 ng/dl). There was a strong correlation between the 25(OH)D level and THI. Our findings suggest that a large proportion of tinnitus patients suffers from vitamin D deficiency and that the vitamin D level correlates with tinnitus impact. We recommend a vitamin D assessment for all tinnitus patients.

Sleep Disorders in Pediatric Migraine: A Questionnaire-Based Study

There is a high comorbidity between migraine and sleep disorders (SD), with a mutual dependence between sleep and headache. This study aimed to analyze the relationship between headache features (migraine frequency and severity, migraine equivalents, use and efficacy of treatments) and sleep in pediatric migraine. Parents of children and adolescents with migraine completed the Children’s Sleep Habits Questionnaire (CSHQ) and the Epworth Sleepiness Scale for Children and Adolescents (ESS-CHAD) and answered questions about headache characteristics. The presence of SD was defined according to CSHQ score. SD were detected in 72.9% of 140 subjects, but only 5.0% already received a diagnosis. Patients with SD presented statistically significant higher headache frequency (p = 0.031) and higher prevalence of migraine equivalents (p = 0.007). A higher CSHQ total score was associated with higher frequency of severe attacks (p = 0.012) and lower acute drug efficacy (p = 0.003). Significant positive correlations of sleep onset delay, sleep duration and nightwakings subscales with migraine frequency emerged. Our findings indicate that SD are highly prevalent in pediatric migraine and frequently associated with a higher headache severity and lower response to acute therapy, but often remain underdiagnosed. Improving sleep quality could help to reduce migraine intensity and disability and vice versa.

Recent advancements in tension-type headache: a narrative review

INTRODUCTION

Tension-type headache (TTH) is the most common primary headache disorder with a prevalence of up to 78% in general population and huge expenses in terms of health service. Despite its high incidence and impact on life's quality the knowledge on the pathophysiology and efficacious treatment of TTH was still limited.

AREAS COVERED

In recent years, a series of studies highlighted the heterogeneous nature of this pathology that seems to be determined by a complex interaction between genetic, environmental, and neuromuscular factors, which result in nociceptive system activation. In this setting, alongside the simple analgesic therapies used during the acute attack, a series of therapeutic options based on newly acquired experiences have taken hold.

EXPERT REVIEW

Not having a single substrate or a typical site of pathophysiology, TTH must be analyzed in a global and multidisciplinary way. Herein, we perform a narrative review of the most recent advancement stimulating the concept of this disease as the tip of the iceberg of a more complex individual malaise secondary to different alterations. Strategies based solely on symptomatic drugs should therefore be avoided by experienced personnel and treatment should aim at taking charge of the patient considering the processes behind this complex pathology.

Metabolic Aspects of Migraine: Association With Obesity and Diabetes Mellitus

Migraine is a disabling neurovascular disorder, characterized by moderate to severe unilateral headaches, nausea, photophobia, and/or phonophobia, with a higher prevalence in women than in men, which can drastically affect the quality of life of migraine patients. In addition, this chronic disorder is related with metabolic comorbidities associated with the patient's lifestyle, including obesity and diabetes mellitus (DM). Beyond the personal and socioeconomic impact caused by migraine, obesity and DM, it has been suggested that these metabolic disorders seem to be related to migraine since: (i) they are a risk factor for developing cardiovascular disorders or chronic diseases; (ii) they can be influenced by genetic and environmental risk factors; and (iii) while clinical and epidemiological studies suggest that obesity is a risk factor for migraine, DM (i.e., type 1 and type 2 DM) have been reported to be either a protective or a risk factor in migraine. On this basis, and given the high worldwide prevalence of migraine, obesity, and DM, this article provides a narrative review of the current literature related to the association between the etiology and pathophysiology of migraine and these metabolic disorders, considering lifestyle aspects, as well as the possible involvement of neurotransmitters, neuropeptides, and/or sex hormones. While a link between migraine and metabolic disorders has been suggested, many studies are contradictory and the mechanisms involved in this association are not yet sufficiently established. Therefore, further research should be focused on understanding the possible mechanisms involved.

Vitamin D Levels in COVID-19 Outpatients from Western Mexico: Clinical Correlation and Effect of Its Supplementation

BACKGROUND

The immunomodulatory effects of vitamin D are known to be beneficial in viral infections; it is also known that its deficiency is associated with a prognosis more critical of Coronavirus Disease 2019. This study aimed to determine baseline vitamin D serum concentrations and the effects of its supplementation in asymptomatic or mildly symptomatic Coronavirus Disease 2019 outpatients.

METHODS

42 outpatients were included, 22 of which received a supplement of 10,000 IU of vitamin D3 for 14 days; the remaining 20 outpatients were designated as a control group. Serum levels of transferrin, ferritin, vitamin D, and D-dimer were measured at baseline in both groups. After 14 days, serum levels of total vitamin D were determined in the supplemented group.

RESULTS

At baseline, only 19% of infected outpatients had vitamin D levels corresponding to sufficiency. All outpatients with vitamin D insufficiency had at least one symptom associated with the disease, while only 75% of patients with symptoms presented sufficiency. On the seventh and fourteenth day of follow-up, the supplemented group presented fewer symptoms with respect to those non-supplemented. A vitamin D3 dose of 10,000 IU/daily for 14 days was sufficient to raise vitamin D serum concentrations.

CONCLUSIONS

Immunomodulatory effects of vitamin D appear to be linked to the development of symptoms in positive outpatients. Vitamin D supplementation could have significant benefits in the Western Mexican population.

Vitamin D and Temporomandibular Disorders: What Do We Know So Far?

Background and aims. Vitamin D is synthesized in the skin with the aid of ultraviolet-B radiation, playing a variety of roles in the body. Temporomandibular disorders (TMDs) are a group of pathological conditions involving the temporomandibular joints as well as the masticatory muscles and othersurrounding tissues. In the present narrative review, we investigated the potential role of vitamin D in the etiology of temporomandibular disorders in order todetermine whether the current knowledge supports 25-hidroxyvitamin D (25-OHD) supplementation in temporomandibular disorders associated with insufficient or deficient levels of vitamin D. Methods. A literature research was performed in PubMed, Scopus, Science Direct, and Google Scholar databases, and a total of 10 articles were included for analysis. Results.Among the observational studies published to date, investigating the role for vitamin D in the etiology of TMDs, six of them suggest that there is a connection between the two aspects. In this context, patients suffering from TMD, with deficient levels of vitamin D (<30 ng/mL), are most likely to benefit from supplementation, whereas individuals with vitamin D level >50ng/mL probably have little benefit from supplementation.Conclusion.Vitamin D might be a safe, simple, and potentially beneficial way to prevent TMDs or to reduce pain; however, more randomized and placebo-controlled trials are required before any firm conclusions can be drawn.