Cytokines in primary headache disorders: a systematic review and meta-analysis

BACKGROUND

The role of inflammation and cytokines in the pathophysiology of primary headache disorders is uncertain. We performed a systematic review and meta-analysis to synthesise the results of studies comparing peripheral blood cytokine levels between patients with migraine, tension-type headache, cluster headache, or new daily persistent headache (NDPH), and healthy controls; and in migraine between the ictal and interictal stages.

METHODS

We searched PubMed/Medline and Embase from inception until July 2022. We included original research studies which measured unstimulated levels of any cytokines in peripheral blood using enzyme-linked immunosorbent assay or similar assay. We assessed risk of bias using the Newcastle-Ottawa Quality Assessment Scale. We used random effects meta-analysis with inverse variance weighted average to calculate standardised mean difference (SMD), 95% confidence intervals, and heterogeneity for each comparison. This study is registered with PROSPERO (registration number CRD42023393363). No funding was received for this study.

RESULTS

Thirty-eight studies, including 1335 patients with migraine (32 studies), 302 with tension-type headache (nine studies), 42 with cluster headache (two studies), and 1225 healthy controls met inclusion criteria. Meta-analysis showed significantly higher interleukin (IL)-6 (SMD 1.07, 95% CI 0.40-1.73, p = 0.002), tumour necrosis factor (TNF)-α (SMD 0.61, 95% CI 0.14-1.09, p = 0.01), and IL-8 (SMD 1.56, 95% CI 0.03-3.09, p = 0.04), in patients with migraine compared to healthy controls, and significantly higher interleukin-1β (IL-1β) (SMD 0.34, 95% CI 0.06-0.62, p = 0.02) during the ictal phase of migraine compared to the interictal phase. Transforming growth factor (TGF)-β (SMD 0.52, 95% CI 0.18-0.86, p = 0.003) and TNF-α (SMD 0.64, 95% CI 0.33-0.96, p = 0.0001) were both higher in patients with tension-type headache than controls.

CONCLUSIONS

The higher levels of the proinflammatory cytokines IL-6, IL-8 and TNF-α in migraine compared to controls, and IL-1β during the ictal stage, suggest a role for inflammation in the pathophysiology of migraine, however prospective studies are required to confirm causality and investigate the mechanisms for the increase in cytokine levels identified. Cytokines may also have a role in tension-type headache. Due a lack of data, no conclusions can be made regarding cluster headache or NDPH.

Examining the correlation between salivary cytokine concentrations and CRP in people experiencing social-cognitive stress

OBJECTIVES

The study aims to determine the relationship of migraine and chronic tension-type headache (TTHs) with alterations in the salivary markers of inflammation .

METHODS

The prospective study involved 75 patients . The concentrations of inflammatory markers (CRP, IL-1 β, and IL-6) in migraine and chronic TTH patients were determined in distinct time points: headache-free period (interictal period), during headache (ictal period), day after headache attack. The STAI-Y (State Trait Anxiety Inventory - Y) and BDI (Beck Depression Inventory) questionnaires were used to measure the level of anxiety and depression in the interictal and ictal periods.

RESULTS

The interictal levels of CRP, IL1-β, and IL-6 were significantly higher in headache groups compared to healthy controls (p < 0.001). Differences in the ictal concentrations were even stronger. Twenty-four hours after headache attack, patients with migraine and chronic TTH experienced a decrease in CRP, IL1-β, and IL-6 levels; yet, those levels were still higher compared with the interictal ones. The repeated analysis of variance revealed no significant statistical differences in CRP, IL-β, and IL-6 levels between the migraine and TTH groups over time (p > 0.05). Statistically higher levels of anxiety and depression were seen in unhealthy groups (p < 0.01).

CONCLUSIONS

The relationship of CRP, IL1-β, and IL-6 concentrations with migraine and chronic TTH has been established. No statistically significant differences were found in the dynamics between migraine and chronic TTH groups. There was a direct correlation of migraine and chronic TTH with anxiety and depression.

Role of SARS-CoV-2-induced Cytokine Storm in Multi-Organ Failure: Molecular Pathways and Potential Therapeutic Options

Coronavirus disease 2019 (COVID-19) outbreak has become a global public health emergency and has led to devastating results. Mounting evidence proposes that the disease causes severe pulmonary involvement and influences different organs, leading to a critical situation named multi-organ failure. It is yet to be fully clarified how the disease becomes so deadly in some patients. However, it is proven that a condition called “cytokine storm” is involved in the deterioration of COVID-19. Although beneficial, sustained production of cytokines and overabundance of inflammatory mediators causing cytokine storm can lead to collateral vital organ damages. Furthermore, cytokine storm can cause post-COVID-19 syndrome (PCS), an important cause of morbidity after the acute phase of COVID-19. Herein, we aim to explain the possible pathophysiology mechanisms involved in COVID-19-related cytokine storm and its association with multi-organ failure and PCS. We also discuss the latest advances in finding the potential therapeutic targets to control cytokine storm wishing to answer unmet clinical demands for treatment of COVID-19.

Immunological findings in patients with migraine and other primary headaches: a narrative review

Experimental findings suggest an involvement of neuroinflammatory mechanisms in the pathophysiology of migraine. Specifically, preclinical models of migraine have emphasized the role of neuroinflammation following the activation of the trigeminal pathway at several peripheral and central sites including dural vessels, the trigeminal ganglion, and the trigeminal nucleus caudalis. The evidence of an induction of inflammatory events in migraine pathophysiological mechanisms has prompted researchers to investigate the human leukocyte antigen (HLA) phenotypes as well as cytokine genetic polymorphisms in order to verify their potential relationship with migraine risk and severity. Furthermore, the role of neuroinflammation in migraine seems to be supported by evidence of an increase in pro-inflammatory cytokines, both ictally and interictally, together with the prevalence of Th1 lymphocytes and a reduction in regulatory lymphocyte subsets in peripheral blood of migraineurs. Cytokine profiles of cluster headache (CH) patients and those of tension-type headache patients further suggest an immunological dysregulation in the pathophysiology of these primary headaches, although evidence is weaker than for migraine. The present review summarizes available findings to date from genetic and biomarker studies that have explored the role of inflammation in primary headaches.

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

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

Nutrient Status in Patients with Frequent Episodic Tension-Type Headache: A Case-Control Study

OBJECTIVE

To investigate the relationship between frequent episodic tension-type headache (FE-TTH) and 25-hydroxyvitamin-D (25(OH)D), folate, vitamin B12, and magnesium.

DESIGN-METHODS

A prospective case-control study involving adults with FETTH and age-sex matched healthy controls (HC) was performed. Individuals under the responsibility of the three provincial Health Centres of the prefecture of Trikala (Central Greece) were recruited during their regular check-up visits. The relationship between FETTH and serum levels of 25(OH)D, vitamin B12, folate, and magnesium was investigated (primary outcomes). Demographics, daily habits, somatometrics, psychometric and sleep quality measurements, laboratory indices, cardiovascular comorbidities and medications taken were also recorded and compared (secondary outcomes). Potential associations of the above-listed parameters with headache parameters (headache frequency, severity and analgesic consumption) were also examined (secondary outcomes).

RESULTS

Between September and December 2020, 30 patients with FETTH and 30 HC were successfully recruited. Demographics, comorbidities, regular medications, smoking habits, alcohol and coffee consumption, body mass index measurements, markers of systemic inflammation, folate and vitamin B12 levels were similar between the two groups (P>0.05). Lower serum 25(OH)D was both univariately (P<0.001) and multivariately [OR= 0.72, 95%CI=(0.55, 0.94) per 1ng/ml increase] associated with FETTH, while serum magnesium was found lower in FETTH only according to the univariate approach (P=0.036). Higher levels of depression (P=0.050) and anxiety (P=0.020), as well as poor quality of sleep (P=0.008), were univariately associated with FETTH. Only the effect of anxiety remained significant following the multivariate logistic regression [OR=7.90, 95%CI=(1.00, 62.47)]. Headache parameters were not associated with any one of the assessed variables.

DISCUSSION

Lower serum 25(OH)D was related to the presence of FETTH. This finding could imply a potential role for vitamin D in the pathophysiology of TTH.

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.

Evaluation of Neutrophil-to-Lymphocyte Ratio, Platelet-to-Lymphocyte Ratio, and C-Reactive Protein in Tension-Type Headache Patients

Objectives  A tension headache is the most common type of headache, and its causes are multifactorial. A relationship has been shown between migraine headaches and neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and C-reactive protein (CRP). In this study, we investigated the NLR, PLR, and serum CRP levels in frequent episodic tension-type headache (FETTH) and chronic tension-type headache (CTTH) patients.

Materials and Methods  This retrospective study included 64 patients with FETTH, 80 patients with CTTH, and 60 healthy controls who were followed up in the neurology clinic. Hematological parameters were compared between the patient and control groups.

Results  In CTTH patients, platelets, NLR, PLR, and CRP values were statistically higher than in FETTH patients and patients in the control group. In FETTH patients, the PLR value was higher than in patients in the control group, but there was no statistically significant difference in NLR and CRP values between FETTH patients and patients in the control group. Also, there was no correlation between these values and age and gender.

Conclusion  Increase platelet count might have an effect on tension-type headache pathophysiology. Systemic inflammation parameters were shown to be significantly higher in CTTH patients. More comprehensive studies are needed to evaluate the effect of systemic inflammation on the chronicity of tension headaches.

Cytokine and interleukin profile in patients with headache and COVID-19: A pilot, CASE-control, study on 104 patients

Background

The presence of headache during the acute phase of COVID-19 could be associated with the innate response and the cytokine release. We aim to compare the cytokine and interleukin profile in hospitalized COVID-19 patients at the moment of admission with and without headache during the course of the disease.

Methods

An observational analytic study with a case control design was performed. Hospitalized patients from a tertiary hospital with confirmed COVID-19 disease were included. Patients were classified into the headache or the control group depending on whether they presented headache not better accounted for by another headache disorder other than acute headache attributed to systemic viral infection. Several demographic and clinical variables were studies in both groups. We determined the plasmatic levels of 45 different cytokines and interleukins from the first hospitalization plasma extraction in both groups.

Results

One hundred and four patients were included in the study, aged 67.4 (12.8), 43.3% female. Among them, 29 (27.9%) had headache. Patients with headache were younger (61.8 vs. 69.5 years, p = 0.005) and had higher frequency of fever (96.6 vs. 78.7%, p = 0.036) and anosmia (48.3% vs. 22.7%, p = 0.016). In the comparison of the crude median values of cytokines, many cytokines were different between both groups. In the comparison of the central and dispersion parameters between the two groups, GROa, IL-10, IL1RA, IL-21, IL-22 remained statistically significant. After adjusting the values for age, sex, baseline situation and COVID-19 severity, IL-10 remained statistically significant (3.3 vs. 2.2 ng/dL, p = 0.042), with a trend towards significance in IL-23 (11.9 vs. 8.6 ng/dL, p = 0.082) and PIGF1 (1621.8 vs. 110.6 ng/dL, p = 0.071).

Conclusions

The higher levels of IL-10 -an anti-inflammatory cytokine- found in our sample in patients with headache may be explained as a counteract of cytokine release, reflecting a more intense immune response in these patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s10194-021-01268-w.

Acupoints for Tension-Type Headache: A Literature Study Based on Data Mining Technology

Objectives

This study aimed to explore the characteristics and principles of acupoints, which were applied for treating tension-type headache (TTH).

Methods

Four databases were searched for the literature studies of treating TTH with acupuncture and moxibustion up to September 1, 2020. Titles, journals, authors, key words, interventions, main acupoints, and outcomes of the included literature studies were extracted and inputted into the self-established Data Excavation Platform of Acupoint Specificity for analysis.

Results

In total, 128 papers containing 137 prescriptions, 89 meridian acupoints, and 7 extraordinary acupoints of treating TTH with acupuncture and moxibustion were included. The total frequency of acupoints' application was 763 times. Fengchi (GB20), Baihui (GV20), Taiyang (EX-HN5), Hegu (LI4), and Taichong (LR3) were used most frequently. The acupoints in Yang meridians were utilized more than those in Yin meridians (66.1% vs. 17.8%), and the acupoints in the Gallbladder Meridian of Foot Shaoyang were applied most commonly. 59.9% (457/763) of the applied acupoints were on the head, face, and neck, and 31.7% (242/763) were on the four limbs. Additionally, the proportion of specific acupoints' application was 78.2% (597/763).

Conclusions

The prescription of Fengchi (GB20), Baihui (GV20), Taiyang (EX-HN5), Hegu (LI4), and Taichong (LR3) might be relatively reasonable in clinical practices of treating TTH with acupuncture, which should be verified in further studies.

Italian folk plant-based remedies to heal headache (XIX-XX century)

BACKGROUND

Headache has been recognized since antiquity. From the late nineteenth to the early to mid-twentieth century, Italian folk remedies to treat headache were documented in a vast corpus of literature sources.

AIM

The purpose of this paper is to bring to light the plant-based treatments utilized by Italian folk medicine to heal headache in an attempt to discuss these remedies from a modern pharmacological point of view. Moreover, we compare the medical applications described by Hippocrates, Pliny the Elder, Dioscorides, Galen and Serenus Sammonicus with those utilized by Italian folk medicine to check if they result from a sort of continuity of use by over two thousand years.

RESULTS

A detailed search of the scientific data banks such as Medline and Scopus was undertaken to uncover recent results concerning the anti-inflammatory, anti-nociceptive and analgesic activities of the plants. Fifty-eight (78.4%) plant-based remedies have shown in vivo, in vitro or in human trials a large spectrum of anti-inflammatory, anti-nociceptive and analgesic activities. Moreover, thirty-one of remedies (41.9%) were already included in the pharmacopoeia between the 5th century BC and the 2nd century AD.

CONCLUSION

Italian folk medicine could be a promising source of knowledge and could provide evidences for active principles that have not as of yet been fully used for their potential.

Loss of Microglia and Impaired Brain-Neurotrophic Factor Signaling Pathway in a Comorbid Model of Chronic Pain and Depression

Major depressive disorder (MDD) and chronic pain are two complex disorders that often coexist. The underlying basis for this comorbidity is unknown. In the current investigation, microglia and the brain-derived neurotrophic factor (BDNF)-cAMP response element-binding protein (CREB) pathway were investigated. A comorbidity model, with characteristics of both MDD and chronic pain, was developed by the administration of dextran sodium sulfate (DSS) and the induction of chronic unpredictable psychological stress (CUS). Mechanical threshold sensory testing and the visceromotor response (VMR) were employed to measure mechanical allodynia and visceral hypersensitivity, respectively. RT-qPCR and western blotting were used to assess mRNA and protein levels of ionized calcium-binding adaptor molecule 1 (Iba-1), nuclear factor-kappa B (NF-κB), nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha (IκBa), BDNF, and CREB. In comorbid animals, mechanical allodynia and visceral hypersensitivities were significant with increased mRNA and protein levels for NF-κB-p65 and IκBa. Furthermore, the comorbid animals had deceased mRNA and protein levels for Iba-1, BDNF, and CREB as well as a reduced number and density of microglia in the medial prefrontal cortex (mPFC). These results together suggest that DSS and CUS can induce the comorbidities of chronic pain and depression-like behavior. The pathology of this comorbidity involves loss of microglia within the mPFC with subsequent activation of NF-κB-p65 and down-regulation of BDNF/p-CREB signaling.

Serum levels of adiponectin, CCL3/MIP-1α, and CCL5/RANTES discriminate migraine from tension-type headache patients

OBJECTIVES

Inflammatory molecules and neurotrophic factors are implicated in pain modulation; however, their role in primary headaches is not yet clear. The aim of this study was to compare the levels of serum biomarkers in migraine and tension-type headache.

METHODS

This was a cross-sectional study. We measured serum levels of adiponectin, chemokines, and neurotrophic factors in patients with migraine and tension-type headache. Depression and anxiety symptoms, headache impact and frequency, and allodynia were recorded.

RESULTS

We included sixty-eight patients with migraine and forty-eight with tension-type headache. Cutaneous allodynia (p = 0.035), CCL3/MIP-1α (p = 0.041), CCL5/RANTES (p = 0.013), and ADP (p = 0.017) were significantly higher in migraine than in tension-type headache. The differences occurred independently of anxiety and depressive symptoms, frequency and impact of headache, and the presence of pain.

CONCLUSIONS

This study showed higher CCL3/MIP-1α, CCL5/RANTES, and ADP levels in migraine in comparison with tension-type headache. Our findings suggest distinctive roles of these molecules in the pathophysiology of these primary headaches.

Headaches and Risk of Dementia

BACKGROUND

Primary headaches include migraines, tension-type headaches and other primary headache syndromes. Migraines and tension-type headaches are associated with patient discomfort and other diseases. This study aimed to investigate the association between primary headaches and the risk of developing dementia, and to clarify the association between different types of headaches and dementia.

MATERIALS AND METHODS

We conducted a nationwide matched cohort population-based study. A total of 3,620 patients with newly diagnosed primary headaches, including migraines and tension-type headaches, between January 1 and December 31, 2000 were selected from the National Health Insurance Research Database of Taiwan, along with 10,860 controls matched for sex and age. After adjusting for confounding factors, Fine and Gray׳s competing risk analysis was used to compare the risk of developing dementia during 10 years of follow-up.

RESULTS

Of the study subjects, 170 (4.70 %) developed dementia compared with 433 (3.99%) of the controls. Fine and Gray׳s competing risk analysis revealed that the study subjects were more likely to develop dementia (hazard ratio = 2.057; 95% CI: 1.718-2.462; P < 0.001). After adjusting for sex, age, monthly income, urbanization level, geographic region of residence and comorbidities, the hazard ratio for dementia was 2.048 (95% CI: 1.705-2.461, P < 0.001). Migraines and tension-type headaches were associated with nonvascular dementia but not vascular dementia.

CONCLUSIONS

The patients with headaches had a 105% increased risk of dementia. Further studies are needed to elucidate the underlying mechanisms.

Reduced serum levels of adiponectin in tension-type headache

BACKGROUND AND OBJECTIVES

Inflammatory mediators have been studied in tension type headache (TTH) pathophysiology; however, their role is not yet well established. The aim of the present study was to investigate adiponectin (ADP) and its association with clinical parameters and psychiatric comorbidities in TTH patients.

METHODS

This was a cross sectional study including TTH patients and controls. Beck Depression (BDI) and Anxiety (BAI) Inventories, and Headache Impact Test (HIT-6) were recorded. Serum levels of ADP were measured by ELISA.

RESULTS

Forty-eight TTH patients and forty-eight controls without headache were enrolled in the study. ADP levels were significantly lower among patients with TTH [31.1 (20.4-69.20) versus 37.8 (24.9-71.4) ng/mL (P=0.008)]. ADP levels were not influenced by BDI and BAI scores, body mass index (BMI), or HIT-6.

CONCLUSION

ADP levels were reduced in TTH, independently of psychiatric comorbidities, BMI, and headache impact.