Long COVID and especially headache syndromes.

PURPOSE OF REVIEW: This is an expert overview on recent literature about the complex relationship between coronavirus disease 2019 (COVID-19) and headache. RECENT FINDINGS: Long COVID is a clinical syndrome characterized by the presence of persistent symptoms following the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Headache is one of the most common symptoms and is described most often as throbbing pain, associated with photo and phonofobia and worsening with physical exercise. In acute COVID-19, headache is usually described as moderate or severe, diffuse and oppressive although sometimes it has been described with a migraine-like phenotype, especially in patients with a previous history of migraine. Headache intensity during acute phase seems to be the most important predictor of duration of headache over time. Some COVID-19 cases can be associated with cerebrovascular complications, and red flags of secondary headaches (e.g. new worsening or unresponsive headache, or new onset of neurological focal signs) should be urgently investigated with imaging. Treatment goals are the reduction of number and intensity of headache crises, and the prevention of chronic forms. SUMMARY: This review can help clinicians to approach patients with headache and infection from SARS-CoV-2, with particular attention to persistent headache in long COVID.

New drugs targeting calcitonin gene-related peptide for the management of migraines.

INTRODUCTION: Significant advances in migraine research have contributed to the development of new drugs for the treatment of migraine. Monoclonal antibodies (mAbs) against Calcitonin Gene-Related Peptide (CGRP) or its receptor and CGRP receptor antagonists (gepants) have been associated with a good safety profile and resulted in an overall efficacy in reducing the number of monthly migraine days both in episodic and chronic forms of migraine. AREAS COVERED: The results from main investigation studies (phase 2 or 3) of CGRP-targeting drugs (both anti-CGRP mAbs and gepants) are reported in this expert-opinion review. EXPERT OPINION: The introduction of new drugs targeting CGRP is a significant breakthrough in the migraine field, and represents a new generation of therapeutic agents that are available to manage migraine. The evaluation of efficacy and safety in the long-term follow-up and the development of trials comparing the available drugs could improve the current knowledge. The economic sustainability of these drugs remains to be clarified, and a cost-cutting campaign should be promoted based on the high burden of migraine.

Common Clinical and Molecular Pathways between Migraine and Sarcoidosis.

Migraine and sarcoidosis are two distinct medical conditions that may have some common biological and clinical pathways. Sarcoidosis is a chronic granulomatous disease characterized by the formation of granulomas in various organs, including the lungs, skin, cardiovascular system, lymph nodes, and brain. Migraine is a common comorbidity in sarcoidosis patients and a common neurological disorder characterized by recurrent headaches that can be accompanied by other symptoms, such as nausea, vomiting, and sensitivity to light and sound. There have been several reports of individuals with neurosarcoidosis experiencing migraines, though the exact relationship between the two disorders is not well understood. Both conditions have been associated with inflammation and the activation of the immune system. In sarcoidosis, the formation of granulomas is thought to be an immune response to the presence of an unknown antigen. Similarly, the pain and other symptoms associated with migraines are thought to be caused by inflammation in the brain and the surrounding blood vessels. There is also evidence to suggest an interplay of environmental and genetic factors playing a role in both conditions, but evidence is inconsistent with the hypothesis of shared genetic susceptibility. This review aims to illustrate common clinical and biological pathways between migraine and sarcoidosis, including inflammation and dysregulation of the immune system, with a focus on the cumulative burden of concurrent disorders and therapeutic implications.

Prognostic Significance of Chest Imaging by LUS and CT in COVID-19 Inpatients: The ECOVID Multicenter Study.

BACKGROUND: Point-of-care lung ultrasound (LUS) score is a semiquantitative score of lung damage severity. High-resolution computed tomography (HRCT) is the gold standard method to evaluate the severity of lung involvement from the novel coronavirus disease (COVID-19). Few studies have investigated the clinical significance of LUS and HRCT scores in patients with COVID-19. Therefore, the aim of this study was to evaluate the prognostic yield of LUS and of HRCT in COVID-19 patients. METHODS: We carried out a multicenter, retrospective study aimed at evaluating the prognostic yield of LUS and HRCT by exploring the survival curve of COVID-19 inpatients. LUS and chest CT scores were calculated retrospectively by 2 radiologists with >10 years of experience in chest imaging, and the decisions were reached in consensus. LUS score was calculated on the basis of the presence or not of pleural line abnormalities, B-lines, and lung consolidations. The total score (range 0-36) was obtained from the sum of the highest scores obtained in each region. CT score was calculated for each of the 5 lobes considering the anatomical extension according to the percentage parenchymal involvement. The resulting overall global semiquantitative CT score was the sum of each single lobar score and ranged from 0 (no involvement) to 25 (maximum involvement). RESULTS: One hundred fifty-three COVID-19 inpatients (mean age 65 ± 15 years; 65% M), including 23 (15%) in-hospital deaths for any cause over a mean follow-up of 14 days were included. Mean LUS and CT scores were 19 ± 12 and 10 ± 7, respectively. A strong positive linear correlation between LUS and CT scores (Pearson correlation r = 0.754; R2 = 0.568; p < 0.001) was observed. By ROC curve analysis, the optimal cut-point for mortality prediction was 20 for LUS score and 4.5 for chest CT score. According to Kaplan-Meier survival analysis, in-hospital mortality significantly increased among COVID-19 patients presenting with an LUS score ≥20 (log-rank 0.003; HR 9.87, 95% CI: 2.22-43.83) or a chest CT score ≥4.5 (HR 4.34, 95% CI: 0.97-19.41). At multivariate Cox regression analysis, LUS score was the sole independent predictor of in-hospital mortality yielding an adjusted HR of 7.42 (95% CI: 1.59-34.5). CONCLUSION: LUS score is useful to stratify the risk in COVID-19 patients, predicting those that are at high risk of mortality.

Comparing the relative and absolute effect of erenumab: is a 50% response enough? Results from the ESTEEMen study.

BACKGROUND: Monoclonal antibodies acting on the calcitonin gene-related peptide (CGRP) or its receptor have changed migraine preventive treatment. Those treatments have led to reconsidering the outcomes of migraine prevention. Available data mostly considered benefits in terms of relative efficacy (percent or absolute decrease in monthly migraine days [MMDs] or headache days compared with baseline). However, not enough attention has been paid to residual MMDs and/or migraine-related disability in treated patients. In the present study, we aimed at comparing the relative and absolute efficacy of erenumab. METHODS: ESTEEMen was a collaborative project among 16 European headache centers which already performed real-life data collections on patients treated with erenumab for at least 12 weeks. For the present study, we performed a subgroup analysis on patients with complete data on MMDs at baseline and at weeks 9-12 of treatment. Starting from efficacy thresholds proposed by previous literature, we classified patients into 0-29%, 30-49%, 50-74%, and ≥75% responders according to MMD decrease from baseline to weeks 9-12 of treatment. For each response category, we reported the median MMDs and Headache Impact test-6 (HIT-6) scores at baseline and at weeks 9-12. We categorized the number of residual MMDs at weeks 9-12 as follows: 0-3, 4-7, 8-14, ≥15. We classified HIT-6 score into four categories: ≤49, 50-55, 56-59, and ≥60. To keep in line with the original scope of the ESTEEMen study, calculations were performed in men and women. RESULTS: Out of 1215 patients, at weeks 9-12, 381 (31.4%) had a 0-29% response, 186 (15.3%) a 30-49% response, 396 (32.6%) a 50-74% response, and 252 (20.7%) a ≥75% response; 246 patients (20.2%) had 0-3 residual MMDs, 443 (36.5%) had 4-7 MMDs, 299 (24.6%) had 8-14 MMDs, and 227 (18.7%) had ≥15 MMDs. Among patients with 50-74% response, 246 (62.1%) had 4-7 and 94 (23.7%) 8-14 residual MMDs, while among patients with ≥75% response 187 (74.2%) had 0-3 and 65 (25.8%) had 4-7 residual MMDs. CONCLUSIONS: The present study shows that even patients with good relative response to erenumab may have a clinically non-negligible residual migraine burden. Relative measures of efficacy cannot be enough to thoroughly consider the efficacy of migraine prevention.

Early outcomes of migraine after erenumab discontinuation: data from a real-life setting.

BACKGROUND: Monoclonal antibodies targeting the calcitonin gene-related peptide, including erenumab, are migraine-specific preventive treatments, whose long-term effectiveness has still to be evaluated in real-life settings. We assessed early outcomes of erenumab discontinuation after a 52-week treatment in patients with a continuous positive response to the drug. METHODS: We evaluated the early outcomes after treatment completion in migraineurs from a real-life multicenter register. All patients received monthly erenumab for 52 weeks and attended a 8-week follow-up after treatment completion. Primary outcomes were responder rates and changes in monthly migraine days (MMDs), acute medications days (AMDs), and pain intensity on a Numerical Rating Scale (NRS score) during weeks 1-4 after erenumab treatment completion. RESULTS: The 32 included patients reported a decrease in MMDs, AMDs, and NRS score during the last 4 weeks of treatment compared with baseline (P<0.001). During weeks 1-4 after treatment completion, all the outcome measures increased compared with the last 4 weeks of treatment (P < 0.001) despite staying lower than baseline (MMDs and AMDs P < 0.001, NRS score P = 0.005). Over the same time frame, 18 (56%) patients maintained a ≥ 50% reduction from baseline in MMDs. At week 4 after treatment completion, 10 (31%) patients restarted treatment due to disease rebound to baseline levels. CONCLUSIONS: More than half patients had an early disease worsening, while the remaining patients maintained their responder status during weeks 1-4 after treatment completion. Further studies might identify predictors of prolonged response to erenumab and define the optimal treatment duration according to patients' characteristics.

Association between response to triptans and response to erenumab: real-life data.

BACKGROUND: Triptans and erenumab are both migraine-specific agents acting on the calcitonin gene-related peptide pathway. Therefore, response to triptans might be associated with response to erenumab. MAIN BODY: In our study, consecutive patients referring to the Headache Centers of the Abruzzo region from January 2019 to March 2020 and treated with erenumab were interviewed about past use and efficacy of triptans. Triptan users were classified as 'triptan responders' if they were headache-free 2 h after treating ≥3 migraine attacks with ≥1 triptan. We considered patients as 'erenumab responders', if they had a ≥ 50% mean reduction in monthly migraine days between the 4th and the 6th month from treatment start compared with baseline. Of 91 triptan users, 73 (80.2%) were triptan responders and 58 (63.7%) were erenumab responders. The odds ratio of being erenumab responder was 3.64 (95% CI, 1.25-10.64) for triptan users as compared to non-users. (P = 0.014). Besides, starting erenumab improved triptan response in both erenumab responders and non-responders. CONCLUSIONS: Our data of an association between response to triptans and response to erenumab can be useful for patient advice and to improve the understanding of migraine pathophysiology and treatment.

Co-occurrence of pain syndromes.

Many pain conditions in patients tend to co-occur, influencing the clinical expressions of each other in various ways. This paper summarizes the main concurrent pain conditions by analyzing the major interactions observed. In particular, co-occurrence will be examined in: visceral pain (especially ischemic heart disease, irritable bowel syndrome, dysmenorrhea/endometriosis and urinary pain), fibromyalgia, musculoskeletal pain and headache. Two concurrent visceral pains from internal organs sharing at least part of their central sensory projection can give rise to viscero-visceral hyperalgesia, i.e., enhancement of typical pain symptoms from both districts. Visceral pain, headache and musculoskeletal pains (myofascial pain from trigger points, joint pain) can enhance pain and hyperalgesia from fibromyalgia. Myofascial pain from trigger points can perpetuate pain symptoms from visceral pain conditions and trigger migraine attacks when located in the referred pain area from an internal organ or in cervico-facial areas, respectively. The pathophysiology of these pain associations is complex and probably multifactorial; among the possible processes underlying the mutual influence of symptoms recorded in the associations is modulation of central sensitization phenomena by nociceptive inputs from one or the other condition. A strong message in these pain syndrome co-occurrence is that effective treatment of one of the conditions can also improve symptoms from the other, thus suggesting a systematic and thorough evaluation of the pain patient for a global effective management of his/her suffering.

Conversion from chronic to episodic migraine in patients treated with erenumab: real-life data from an Italian region.

BACKGROUND: Most patients treated with erenumab in clinical practice have chronic migraine (CM). We assessed the rate and possible predictors of conversion from CM to episodic migraine (EM) in a real-life study. MAIN BODY: We performed a subgroup analysis of patients treated with erenumab from January 2019 to February 2020 in the Abruzzo region, central Italy. Treatment was provided according to current clinical practice. For the purpose of the present study, we included patients fulfilling the definition of CM for the three months preceding erenumab treatment and with at least 6 months of follow-up after treatment. We assessed the rate of conversion to EM from baseline to Months 4-6 of treatment and during each month of treatment. To test the clinical validity of conversion to EM, we also assessed the decrease in monthly headache days (MHDs), acute medication days, and median headache intensity on a Numerical Rating Scale (NRS). We included in our study 91 patients with CM. At Months 4-6, 62 patients (68.1%) converted from CM to EM; the proportion of converters increased from Month 1 to Month 5. In the overall group of patients, median MHDs decreased from 26.5 (IQR 20-30) to 7.5 (IQR 5-16; P < 0.001) compared with baseline, while median acute medication days decreased from 21 (IQR 16-30) to 6 (IQR 3-10; P < 0.001) and median NRS scores decreased from 8 (IQR 7-9) to 6 (IQR 4-7; P < 0.001). Significant decreases were found both in converters and in non-converters. We found no significant predictors of conversion to EM among the patients' baseline characteristics. CONCLUSIONS: In our study, two thirds of patients with CM converted to EM during 6 months of treatment with erenumab. MHDs, acute medication use, and headache intensity decreased regardless of conversion from CM to EM.

Real-life data on the efficacy and safety of erenumab in the Abruzzo region, central Italy.

BACKGROUND: We aimed to assess the efficacy and safety of erenumab, a fully human monoclonal antibody inhibiting the calcitonin gene-related peptide receptor (CGRPr), for the prevention of migraine in a real-life setting. MAIN BODY: We included in our observational study all patients with episodic or chronic migraine treated with erenumab during the year 2019 in the Abruzzo region, central Italy, and with a 6-month follow-up. We included 89 patients; 76 (85.4%) received 6 doses of erenumab, 11 (12.4%) autonomously withdrew the drug due to perceived inefficacy, and 2 (2.2%) due to adverse events. Seventy-eight patients (87.6%) were female, with a mean age of 46.8 ± 11.2 years; 84 (94.4%) had chronic migraine, and 64 (71.9%) medication overuse. All patients had ≥2 prior preventive treatment failures. Fifty-three patients (69.7%) had a 50% decrease in monthly migraine days (MMDs) within the first three doses; 46 (71.9%) of 64 patients withdrew medication overuse. In the 76 patients who completed a 6-dose treatment, erenumab decreased median MMDs from 19 (interquartile range [IQR] 12-27.5) to 4 (IQR 2-9.5; P < 0.001), median monthly days of analgesic use from 10 (IQR 4.5-20) to 2 IQR 0-5; P < 0.001), and median monthly days of triptan use from 5 (IQR 0-15.5) to 1 (IQR 0-4; P < 0.001). We recorded 27 adverse events in 20 (22.5%) patients, the most common being constipation (13.5%). One adverse event, i.e. allergic reaction, led to treatment discontinuation in one patient. CONCLUSIONS: Our real-life data confirm the efficacy and tolerability of erenumab for the prevention of migraine in a difficult-to-treat population of patients with a high prevalence of chronic migraine and medication overuse.

Iron status and oxidative stress in the aged rabbit heart.

Altered iron status may be relevant to the pathophysiology of aging. We have assessed redox-active catalytic low molecular weight iron (LMWI), non-heme iron (NHI), heme iron (HI), and total iron (TI) in the aerobically perfused hearts of aged rabbits (AR, about 4.5years old) and young adult control rabbits (YACR, 3-4months old); myocardial lipid and protein oxidations were also assessed as oxidative stress biomarkers. The levels of LMWI and NHI, as well as of lipid and protein oxidation, were higher, while HI content was lower, in the hearts of AR than in those of YACR; TI did not differ significantly between the two groups. Together with these findings, hemodynamic dysfunction, namely heightened end-diastolic pressure (EDP) and lowered coronary flow (CF), occurred in the AR hearts. Notably, such pattern of hemodynamic dysfunction associated with myocardial oxidant damage occurred in the hearts of other YACR perfused in the presence of a cell-permeable form of iron, i.e., the iron/hydroxyquinoline complex, pointing to the involvement of catalytic iron in the aged heart damage. Moreover, as shown in other AR, heart perfusion in the presence of the iron chelator deferoxamine (0.6mM or 3.6mM) reduced the myocardial levels of LMWI, without significantly affecting those of NHI, HI, and TI; concomitantly, in AR deferoxamine lowered myocardial lipid and protein oxidation, and reduced EDP with a tendency to augment CF. Instead, deferoxamine, even at high concentration of 3.6mM, had no significant effects in the YACR. In conclusion, altered iron status with catalytic LMWI burden occurs in the aged rabbit heart, eventually resulting in iron-dependent cardiac oxidative stress and hemodynamic dysfunction.

Differential TBXA2 receptor transcript stability is dependent on the C924T polymorphism.

BACKGROUND: In order to better characterize the molecular mechanisms involved in processing mutated transcripts, we investigated the post-transcriptional role of the C924T polymorphism (rs4523) located in the 3' region of the TBXA2R gene. METHODS AND RESULTS: Experiments of dose response with Actinomycin D on MEG-01 human cell line showed a significant decrease on cell viability that was more evident on cells treated for 24h. In addition, we showed that treatments with 5-10µM, 15µM and 20µM of actinomycin D reduced cell viability by 44%, 72% and 75%, respectively, compared to the control group. Conversely, the samples treated with 1µM of actinomycin D did not show significant difference on cell viability as compared to the control group. Analysis of the steady state mRNA level of TBXA2R by qRT-PCR evidenced an increase in mRNA stability for the wild type (C) compared to the mutant (T) allele. Furthermore, the expression levels of TBXA2R on wild type (CC) and mutant type (TT) patients, based on C924T polymorphism, were analyzed. The wild type showed a higher expression of TBXA2 receptor also with two different degrees of glycosylation (55 and 64kDa), when compared to the mutant. These observations correlated with platelet aggregation, which was reduced in TT, independently of the platelet aggregation stimuli. CONCLUSIONS: The instability of the TBXA2R transcript and the lack of effect on platelet aggregation might suggest a protective role for the TBXA2R TT genotype against atherothrombosis and its complications in high-risk aspirin-treated patients.

Effects of topical vs injection treatment of cervical myofascial trigger points on headache symptoms in migraine patients: a retrospective analysis.

BACKGROUND: In migraine patients with cervical myofascial trigger points whose target areas coincide with migraine sites (M + cTrPs), TrP anesthetic injection reduces migraine symptoms, but the procedure often causes discomfort. This study evaluated if a topical TrP treatment with 3% nimesulide gel has similar efficacy as the injection but produces lesser discomfort with higher acceptability by the patients. METHODS: Retrospective analysis of medical charts of M + cTrPs patients in the period January 2012-December 2016 at a single Headache Center. Three groups of 25 patients each were included, all receiving migraine prophylaxis (flunarizine 5 mg/day) for 3 months and symptomatic treatment on demand. Group 1 received no TrP treatment, group 2 received TrP injections (bupivacaine 5 mg/ml at basis, 3rd, 10th, 30th and 60th day), group 3 received daily TrP topical treatment with 1.5 g of 3% nimesulide gel for 15 consecutive days, 15 days interruption and again 15 consecutive days. The following were evaluated: monthly number of migraine attacks and rescue medications, migraine intensity; pain thresholds to skin electrical stimulation (EPTs) and muscle pressure stimulation (PPTs) in TrP and target (basis, 30th, 60th and 180th days); discomfort from, acceptability of and willingness to repeat treatment (end of study). ANOVA for repeated measures and 1-way ANOVA were used to assess temporal trends in each group and comparisons among groups, respectively. Significance level was set at p < 0.05. RESULTS: Migraine improved over time in all groups, but significantly more and earlier in those receiving TrP treatment vs no TrP treatment (0.02 < p < 0.0001, 30-180 days for intensity and rescue medication, 60-180 days for number). All thresholds in the non-TrP-treated group did not change over time, while significantly improving in both the injection and nimesulide gel groups (0.01 < p < 0.0001, 30-180 days). Improvement of migraine and thresholds did not differ in the two TrP-treated groups. Discomfort was significantly lower, acceptability and willingness to repeat treatment significantly higher (0.05 < p < 0.0001) with gel than injection. CONCLUSION: In migraine patients, topical treatment of cervical TrPs with 5% nimesulide gel proves equally effective as TrP injection with local anesthetics but more acceptable by the patients. This treatment could be effectively associated to standard migraine prophylaxis to improve therapeutic outcomes.

Use of Nonsteroidal Anti-Inflammatory Drugs for Symptomatic Treatment of Episodic Headache.

INTRODUCTION: Primary headaches have high epidemiologic impact but their symptomatic treatment often remains problematic. Nonsteroidal anti-inflammatory drugs (NSAIDs) are frequently used, but their modality of employment and efficacy/differential efficacy are highly variable. This study investigated current NSAID use for episodic headache at an Italian headache center (January 2000 to February 2013). METHODS: A retrospective evaluation was performed on 6,443 patient records: migraine (n = 2,330), tension-type headache (TTH; n = 807), and migraine plus TTH (n = 3,306). RESULTS: Among migraine patients, 80% had used NSAIDs in the past year. Preferences were: nimesulide (57%), ketoprofen (25%), and ibuprofen (24%); complete efficacy was significantly higher than incomplete/absent efficacy (P < 0.0001). NSAIDs were replaced with triptans in 53% of patients at first visit; after 1 year there was a spontaneous significant return to NSAIDs (56%; P < 0.0005). Among TTH patients, 90% were NSAID users; preferences were: nimesulide (48%), ketoprofen (47%), and diclofenac (19%), with significantly higher complete vs. incomplete/absent efficacy (nimesulide and ketoprofen, P < 0.02). Replacement with analgesics was performed in 24% of patients; after 1 year, there was a 29% return to NSAIDs. Among migraine plus TTH patients, 89% were NSAID users. Preferences were: nimesulide (44%), ibuprofen (42%), and ketoprofen (38%), with significantly higher complete vs. incomplete/absent efficacy (0.001 < P < 0.0001). Replacement with analgesics was performed in 31% of patients; after 1 year, there was a 37% return to NSAIDs. CONCLUSIONS: Nonsteroidal anti-inflammatory drug use in headache was higher than could be hypothesized based on guidelines, with NSAID preferences not entirely coinciding with international recommendations. This outcome suggests the need for greater awareness of all treatment options in headache by both patients and physicians.

Emerging drugs for migraine treatment.

INTRODUCTION: Migraine is a highly prevalent and disabling neurological condition whose personal, social and economic impact is substantial. Abortive and preventative treatments of this condition are still unsatisfactory, with poor control of the acute symptoms of the single attacks in many cases and a frequent progression towards chronicity. AREAS COVERED: The major drug classes recently developed and/or in current development for migraine treatment are discussed. These include: Calcitonin-Gene-Related Peptide (CGRP) receptor antagonists, mAbs against CGRP or its receptor, selective 5 hydroxytryptamine (5-HT)1F receptor agonists, drugs targeting Acid-Sensing Ion Channels, Transient Receptor Potential channels and Nitric Oxide. EXPERT OPINION: The most convincing results appear those obtained with mAbs against CGRP, particularly in migraine preventative treatment, given the absence of serious adverse events, and the good response in terms of pain relief. If these results are confirmed in larger studies, these compounds have the potential to significantly improve the pharmacological control of migraine and also its evolution towards chronicity.

Altered serum levels of kynurenine metabolites in patients affected by cluster headache.

BACKGROUND: The reported efficacy of memantine in the treatment of patients with cluster headache (CH) suggests that NMDA receptors are involved in mechanisms of nociceptive sensitization within the trigeminal system associated with CH. NMDA receptors are activated or inhibited by neuroactive compounds generated by tryptophan metabolism through the kynurenine pathway. In the accompanying manuscript, we have found that serum levels of all kynurenine metabolites are altered in patients with chronic migraine. Here, we have extended the study to patients affected by episodic or chronic CH as compared to healthy controls. METHOD: We assessed serum levels of kynurenine (KYN), kynurenic Acid (KYNA), anthranilic acid (ANA), 3-hydroxy-anthranilic acid (3-HANA), 3-hydroxykynurenine (3-HK), xanthurenic acid (XA), quinolinic acid (QUINA), tryptophan (Trp) and 5-hydroxyindolacetic acid (5-HIAA) by means of a liquid chromatography/tandem mass spectrometry (LC/MS-MS) method in 21 patients affected by CH (15 with episodic and 6 with chronic CH), and 35 age-matched healthy subjects. Patients with psychiatric co-morbidities, systemic inflammatory, endocrine or neurological disorders, and mental retardation were excluded. RESULTS: LC/MS-MS analysis of kynurenine metabolites showed significant reductions in the levels of KYN (-36 %), KYNA (-34 %), 3-HK (-51 %), 3-HANA (-54 %), XA (-25 %), 5-HIAA (-39 %) and QUINA (-43 %) in the serum of the overall population of patients affected by CH, as compared to healthy controls. Serum levels of Trp and ANA were instead significantly increased in CH patients (+18 % and +54 %, respectively). There was no difference in levels of any metabolite between patients affected by episodic and chronic CH, with the exception of KYN levels, which were higher in patients with chronic CH. CONCLUSION: The reduced levels of KYNA (an NMDA receptor antagonist) support the hypothesis that NMDA receptors are overactive in CH. A similar reduction in KYNA levels was shown in the accompanying manuscript in patients affected by chronic migraine. The reduced levels of XA, a putative analgesic compound, may contribute to explain the severity of pain attacks in CH. These data, associated with the data reported in the accompanying manuscript, supports a role for the kynurenine pathway in the pathophysiology of chronic headache disorders.

Impact of migraine on fibromyalgia symptoms.

BACKGROUND: Fibromyalgia (FMS) and high frequency episodic/chronic migraine (M) very frequently co-occur, suggesting common pathophysiological mechanisms; both conditions display generalized somatic hyperalgesia. In FMS-M comorbidity we assessed if: a different level of hyperalgesia is present compared to one condition only; hyperalgesia is a function of migraine frequency; migraine attacks trigger FMS symptoms. METHODS: Female patients with fibromyalgia (FMS)(n.40), high frequency episodic migraine (M1)(n.41), chronic migraine (M2)(n.40), FMS + M1 (n.42) and FMS + M2 (n.40) underwent recording of: -electrical pain thresholds in skin, subcutis and muscle and pressure pain thresholds in control sites, -pressure pain thresholds in tender points (TePs), -number of monthly migraine attacks and fibromyalgia flares (3-month diary). Migraine and FMS parameters were evaluated before and after migraine prophylaxis, or no prophylaxis, for 3 months with calcium-channel blockers, in two further FMS + H1 groups (n.49, n.39). 1-way ANOVA was applied to test trends among groups, Student's t-test for paired samples was used to compare pre and post-treatment values. RESULTS: The lowest electrical and pressure thresholds at all sites and tissues were found in FMS + M2, followed by FMS + H1, FMS, M2 and M1 (trend: p < 0.0001). FMS monthly flares were progressively higher in FMS, FMS + M1 and FMS + M2 (p < 0.0001); most flares (86-87 %) occurred within 12 h from a migraine attack in co-morbid patients (p < 0.0001). Effective migraine prophylaxis vs no prophylaxis also produced a significant improvement of FMS symptoms (decreased monthly flares, increased pain thresholds)(0.0001 < p < 0.003). CONCLUSIONS: Co-morbidity between fibromyalgia and migraine involves heightened somatic hyperalgesia compared to one condition only. Increased migraine frequency - with shift towards chronicity - enhances both hyperalgesia and spontaneous FMS pain, which is reversed by effective migraine prophylaxis. These results suggest different levels of central sensitization in patients with migraine, fibromyalgia or both conditions and a role for migraine as a triggering factor for FMS.

Altered kynurenine pathway metabolites in serum of chronic migraine patients.

BACKGROUND: Activation of glutamate (Glu) receptors plays a key role in the pathophysiology of migraine. Both NMDA and metabotropic Glu receptors are activated or inhibited by metabolites of the kynurenine pathway, such as kynureninic acid (KYNA), quinolinic acid (QUINA), and xanthurenic acid (XA). In spite of the extensive research carried out on KYNA and other kynurenine metabolites in experimental models of migraine, no studies have ever been carried out in humans. Here, we measured all metabolites of the kynurenine pathway in the serum of patients affected by chronic migraine (CM) and age- and gender-matched healthy controls. METHODS: We assessed serum levels of tryptophan (Trp), L-kynurenine (KYN), KYNA, anthranilic acid (ANA), 3-hydroxyanthranilic acid (3-HANA), 3-hydroxykynirenine (3-HK), XA, QUINA, and 5-hydroxyindolacetic acid (5-HIAA) in 119 patients affected by CM (ICHD-3beta criteria) and 84 age-matched healthy subjects. Patients with psychiatric co-morbidities, systemic inflammatory, endocrine or neurological disorders, and mental retardation were excluded. Serum levels of all metabolites were assayed using liquid chromatography/tandem mass spectrometry (LC-MS/MS). RESULTS: LC-MS/MS analysis of kynurenine metabolites showed significant reductions in the levels of KYN (-32 %), KYNA (-25 %), 3-HK (-49 %), 3-HANA (-63 %), 5-HIAA (-36 %) and QUINA (-80 %) in the serum of the CM patients, as compared to healthy controls. Conversely, levels of Trp, ANA and XA were significantly increased in CM patients (+5 %, +339 % and +28 %, respectively). CONCLUSIONS: These findings suggest that in migraine KYN is unidirectionally metabolized into ANA at expenses of KYNA and 3-HK. The reduction in the levels of KYNA, which behaves as a competitive antagonist of the glycine site of NMDA receptors, is consistent with the hypothesis that NMDA receptors are overactive in migraine. The increase in XA, a putative activator of Glu2 receptors, may represent a compensatory event aimed at reinforcing endogenous analgesic mechanisms. The large increase in the levels of ANA encourages research aimed at establishing whether ANA has any role in the regulation of nociceptive transmission.

Correlation between Migraine Severity and Cholesterol Levels.

INTRODUCTION: Several studies have documented increased cardiovascular risk factors, particularly hypercholesterolemia, in the migraine population with respect to controls. However, no studies have investigated the possible relationship between headache severity parameters and lipid serum levels. METHODS: This study evaluated the lipid asset in 52 migraine patients (17 with and 36 without aura) before and after treatment with drugs for migraine prophylaxis for 3 months. RESULTS: High frequency (HF, ≥ 8/month) and intensity (HI, ≥ 5 Numeric Rating Score) vs. low frequency (LF, < 8/month) and intensity (LI, < 5) of crises were associated with significantly higher cholesterol levels, both total (TC, HF vs. LF, P < 0.0001; HI vs. LI, P < 0.0001) and LDL (LDL-c, HF vs. LF, P < 0.0001, and HI vs. LI, P < 0.0001). In treated patients, a significant decrease in number and intensity of crises was associated with a significant reduction of TC and LDL-c (P < 0.001). A direct linear correlation was also found between frequency and intensity of crises and lipid levels (TC/frequency, P < 0.0001; TC/intensity, P < 0.0001; LDL-c/frequency, P < 0.0001; LDL-c/intensity, P < 0.0001). No significant difference was found in the evaluated parameters for the subgroups of patients with and without aura. DISCUSSION: This study shows a significant positive association between migraine frequency and intensity with total and LDL cholesterol, demonstrating for the first time a significant reduction of these lipid parameters after migraine prophylaxis. However, in view of the retrospective design of the study and the small population size, these results should be considered as preliminary, to be confirmed by future prospective controlled trials.

Effects of topical diclofenac plus heparin (DHEP+H plaster) on somatic pain sensitivity in healthy subjects with a latent algogenic condition of the lower limb.

OBJECTIVE: To evaluate whether a diclofenac epolamine + heparin topical (plaster) is more effective than diclofenac plaster alone in reducing deep somatic hyperalgesia in subjects without spontaneous pain and whether the effect is linked to or independent of the anti-edematous action of heparin. DESIGN: Prospective, double-blind, randomized and controlled, four-arm parallel design trial. SUBJECTS: One hundred and four patients (84 women, 20 men, mean age 42.2 ± 13.3 years), with deep somatic hyperalgesia in one thigh, randomly assigned to one of 4 groups of 26 each. INTERVENTION: Each group underwent one of the following plaster treatments on one thigh: diclofenac+heparin; diclofenac; heparin; placebo, for 7 days, renewing the plaster every 24 hours. OUTCOME MEASURES: Before treatment (day 1), at day 4 and day 8, assessment of (a) pressure and electrical pain thresholds of vastus lateralis and overlying subcutis and skin; and (b) structure/thickness of subcutis and muscle with ultrasounds at the same level. RESULTS: During treatment, in placebo and heparin, no significant threshold changes, except subcutis thresholds which increased slightly (P < 0.02); in diclofenac and diclofenac+heparin, significant increase in all thresholds (0.0001 < P < 0.04). Electrical muscle pain thresholds increased significantly more in diclofenac+heparin than in diclofenac, heparin, and placebo (0.0001 < P < 0.04). In all groups: no edema and thickness changes at ultrasounds in muscle and subcutis. CONCLUSIONS: Topical diclofenac+heparin is significantly more effective than diclofenac alone in reducing muscle hyperalgesia in subjects without spontaneous pain, independently of the anti-edematous action of heparin. The results provide a rationale for the use of diclofenac+heparin also in algogenic conditions without evident signs of injury/edema/hematoma.