Calcitonin Gene-Related Peptide Systemic Effects: Embracing the Complexity of Its Biological Roles-A Narrative Review.

The calcitonin gene-related peptide (CGRP) is a neuropeptide widely distributed throughout the human body. While primarily recognized as a nociceptive mediator, CGRP antagonists are currently utilized for migraine treatment. However, its role extends far beyond this, acting as a regulator of numerous biological processes. Indeed, CGRP plays a crucial role in vasodilation, inflammation, intestinal motility, and apoptosis. In this review, we explore the non-nociceptive effects of CGRP in various body systems, revealing actions that can be contradictory at times. In the cardiovascular system, it functions as a potent vasodilator, yet its antagonists do not induce arterial hypertension, suggesting concurrent modulation by other molecules. As an immunomodulator, CGRP exhibits intriguing complexity, displaying both anti-inflammatory and pro-inflammatory effects. Furthermore, CGRP appears to be involved in obesity development while paradoxically reducing appetite. A thorough investigation of CGRP's biological effects is crucial for anticipating potential side effects associated with its antagonists' use and for developing novel therapies in other medical fields. In summary, CGRP represents a neuropeptide with a complex systemic impact, extending well beyond nociception, thus offering new perspectives in medical research and therapeutics.

Rapid response to galcanezumab and predictive factors in chronic migraine patients: A 3-month observational, longitudinal, cohort, multicenter, Italian real-life study.

BACKGROUND AND PURPOSE: A rapid response to preventive therapy is of pivotal importance in severely disabled patients with chronic migraine (CM) and diverse preventive treatment failures. This prospective, observational, multicenter real-life study aimed at investigating the effectiveness of galcanezumab in the first 3 months of treatment of CM patients at 14 Italian headache centers. METHODS: All consecutive adult patients with CM diagnosis with the clinical indication for galcanezumab were considered. We collected patients' baseline characteristics, monthly headache days, monthly painkiller intake, migraine clinical characteristics, and disability scale scores during a 1-month run-in period (baseline) and the first 3 months of therapy. Possible predictive factors of treatment were considered. RESULTS: A total of 156 patients (82.4% female, aged 47.3 ± 12.3 years) were enrolled. The 65 (41.7%) patients with a consecutive ≥50% response rate (RR) in the 3 months of therapy presented a lower body mass index (p = 0.004) and more frequently presented unilateral migraine pain (p = 0.002) and good response to triptans (p = 0.003). Persistent conversion from CM to episodic migraine was observed in 55.8% (87/156) of patients. They more frequently presented a good response to triptans (p = 0.003) and unilateral pain (p = 0.046). At baseline, 131 of 156 (83.9%) patients presented medication overuse (MO). Of these, 61.8% (81/131) no longer displayed MO consistently during the 3 months. These patients were more frequently responders to triptans (p = 0.002) and less frequently suffered from gastrointestinal comorbidity (p = 0.007). CONCLUSIONS: Unilateral pain, good response to triptans, and normal weight may be associated with a persistent positive response in the first 3 months of therapy with galcanezumab in CM patients.

Improving distress perception and mutuality in migraine caregivers after 6 months of galcanezumab treatment.

OBJECTIVE: This prospective cohort, real-life study aimed to evaluate whether galcanezumab, a monoclonal antibody anti-calcitonin gene-related peptide (CGRP) ligand, can reduce caregivers' distress and improve their mutuality with patients. BACKGROUND: Migraine is a highly disabling chronic disease that negatively impacts patients' and often their relatives' lives, occurring during an active phase of life with direct consequences on leisure- and work-related activities. The figure of caregiver is crucial in several neurological conditions but poorly accounted for in migraine care so far. Studies on monoclonal antibodies against the CGRP pathway, recently introduced as migraine-preventive treatments, demonstrated that they significantly reduce migraine frequency and disability in the first weeks of treatment. METHODS: Consecutive patient-caregiver dyads were evaluated at baseline and after 6 months of treatment with galcanezumab (V6) at our headache center from September 2020 to September 2021. Enrolled patients were requested to report their monthly migraine days, monthly intake of acute medications, attack pain intensity (on the Numeric Rating Scale), concomitant preventives, and disability questionnaires (Headache Impact Test, Migraine Disability Assessment). Each dyad filled in the Mutuality Scale to check their reciprocity; moreover, the Relatives' Stress Scale was used to detect caregivers' distress. RESULTS: We enrolled 27 patient-caregiver dyads. At 6 months, migraine burden significantly improved with reductions in monthly migraine days (falling from 14.8 [SD = 4.8] days by 10.3 [SD = 4.8] days; 95% CI: 8.4, 12.2; p < 0.001) and Migraine Disability Assessment scores (lowering from 83.6 [SD = 46.7] by 71.5 points [SD = 49.3]; 95% CI: 51.2, 91.9; p < 0.001). From baseline to month 6, the caregiver Relatives' Stress Scale score significantly decreased (falling from 20.7 [SD = 13.7] by 6.5 [SD = 14.1] points; 95% CI: 0.8, 12.2; p = 0.027), while the Mutuality Scale's caregiver total score increased (from 3.04 [SD = 0.61] by 0.29 [SD = 0.49] points; 95% CI: -0.508, -0.064; p = 0.014). CONCLUSIONS: Our findings preliminarily demonstrated that patients' migraine improvement after 6 months of galcanezumab treatment could be favorably perceived by caregivers, significantly reducing their distress with better reciprocity within the dyad.

Gepants - a long way to cure: a narrative review.

Calcitonin gene-related peptide (CGRP) is probably the most potent vasodilator in cerebral circulation. Forty years after its discovery, the new CGRP-targeted therapy monoclonal antibodies, and the small molecule gepants, are now available for clinical practice. While randomized controlled trials and real-world experience consistently demonstrated the high efficacy and tolerability of monoclonal antibodies, limited evidence is available to characterize gepants fully. Depending on pharmacokinetics, these CGRP receptor antagonists can be used for acute (ubrogepant, rimegepant, and the not yet approved zavegepant) or preventive (atogepant and rimegepant) migraine treatment. Randomized placebo-controlled trials demonstrated gepants efficacy in treating acute attacks to obtain 2 h pain freedom in about 20% of patients and pain relief in about 60%, while up to 60% of treated patients with episodic migraine may experience a 50% reduction in monthly migraine days. The most common treatment-related emergent adverse events were gastrointestinal (nausea, constipation) for the acute or preventive use. No vascular or hepatic concerns have emerged so far. More studies are ongoing to investigate gepant tolerability and safety also if associated with monoclonal antibodies targeting CGRP and other therapeutic classes. Gepants are also under investigation to treat other painful and non-painful conditions. Real-life studies are necessary to confirm the trials' findings and investigate more practical clinical aspects.

Erenumab in the prevention of high-frequency episodic and chronic migraine: Erenumab in Real Life in Italy (EARLY), the first Italian multicenter, prospective real-life study.

OBJECTIVE: To assess the effectiveness, safety, and tolerability of erenumab in a real-life migraine population, while trying to identify responsiveness predictors. BACKGROUND: Erenumab is a fully human Ig-2 monoclonal antibody blocking the calcitonin gene-related peptide receptor, indicated for migraine prophylaxis. Phase II and III trials demonstrated that erenumab is effective, safe, and well tolerated in the prevention of episodic and chronic migraine (CM), showing an early onset of action. METHODS: This is a multicenter, prospective, cohort, and real-life study. We considered for enrolment all consecutive patients aged 18-65 affected by high-frequency episodic migraine (HFEM) or CM, with or without medication overuse, visited at nine Italian Headache Centers from December 20, 2018 to September 30, 2019. Each patient was treated with erenumab 70 mg, administered subcutaneously every 4 weeks. Treatment duration was planned to last from 6 to 12 months, depending on the patient's response. The primary endpoint was the change in monthly migraine days (MMDs) at weeks 9-12 compared to baseline. Secondary endpoints included changes in monthly analgesics intake, ≥50%, ≥75%, and 100% responder rates and any variation in the Visual Analog Scale (VAS) and Headache Impact Test scores (HIT). RESULTS: In total, 372 migraine patients were treated with at least one dose of erenumab 70 mg. At weeks 9-12, erenumab decreased MMDs by 4.5 ± 4.1 days (mean ± SD) in patients with HFEM and by 9.3 ± 9.1 (mean ± SD) days in those with CM compared to baseline. At weeks 9-12 VAS score was reduced by 1.9 ± 1.9 (mean ± SD), HIT score by 10.7 ± 8.8 (mean ± SD), and median monthly analgesics intake passed from 12.0 (interquartile range [IQR] 10.0-14.0) to 5.0 (IQR 3.0-7.0) in HFEM. In CM patients, VAS was reduced by 1.7 ± 2.0 (mean ± SD), HIT by 9.7 ± 10.4 (mean ± SD), and median monthly analgesics intake passed from 20.0 (IQR 15.0-30.0) to 8.0 (IQR 5.0-15.0). At week 12, ≥50% responders were 60/101 (59.4%) for HFEM and 146/263 (55.5%) for CM, ≥75% responders were 17/101 (16.8%) and 59/263 (22.4%) and 100% responders 1/101 (1.0%) and 3/263 (1.1%), respectively. Erenumab responsiveness in HFEM was positively associated with unilateral pain localization (OR: 3.03, 95% CI: 1.24-7.40; p = 0.015), whereas in CM responsiveness was positively associated with and baseline migraine frequency (OR: 1.06, 95% CI:1.02-1.11; p = 0.031), dopaminergic symptoms (OR: 2.01, 95% CI: 1.14-3.52; p = 0.015), and negatively associated with psychiatric comorbidities (OR: 0.43, 95% CI: 0.20-0.93; p = 0.003). CONCLUSIONS: Erenumab 70 mg is effective, safe, and well tolerated in real life. Easily obtainable clinical features might be of help in predicting patient's responsiveness.

Long-term (48 weeks) effectiveness, safety, and tolerability of erenumab in the prevention of high-frequency episodic and chronic migraine in a real world: Results of the EARLY 2 study.

OBJECTIVE: To evaluate the long-term effectiveness, safety, and tolerability of erenumab in a real-world migraine population, looking for putative predictors of responsiveness. BACKGROUND: Erenumab proved to be effective, safe, and well tolerated in the prevention of episodic migraine (EM) and chronic migraine (CM) in long-term extension studies of double-blind, placebo-controlled trials in patients with no more than two (EM) or three (CM) prior preventive treatment failures. METHODS: A 48-week, multicenter, longitudinal cohort real-life study was conducted at 15 headache centers across eight Italian regions between December 20, 2018 and July 31, 2020. We considered all consecutive patients with high-frequency episodic migraine (HFEM) or CM aged 18-65 years. Each patient was treated with erenumab 70 mg, administered monthly. The dose was switched to 140 mg in nonresponders and in responders who had become nonresponders for at least 4 weeks. Change in monthly migraine days (MMDs) or monthly headache days (MHDs) at Weeks 45-48 compared with baseline was the primary efficacy endpoint. Secondary endpoints encompassed variation in monthly analgesic intake, achievement of a ≥50%, ≥75%, or 100% reduction in migraine or headache days, and any change in the Visual Analogue Scale (VAS) and Headache Impact Test-6 scores (HIT-6) during the same time interval. RESULTS: A total of 242 patients with migraine received at least one dose of erenumab 70 mg and were considered for safety analysis, whereas 221 received a monthly erenumab dose for ≥48 weeks and were included in the effectiveness and safety analysis set. All patients had previously been treated unsuccessfully with ≥3 migraine-preventive medication classes. From baseline to Weeks 45-48, erenumab treatment reduced MMD by 4.3 ± 5.3 (mean ± SD) in patients with HFEM, and MHD by 12.8 ± 8.9 (mean ± SD) in subjects with CM. VAS and HIT-6 scores were decreased by 1.8 ± 1.9 (mean ± SD) and 12.3 ± 11 (mean ± SD) in HFEM, and by 3.0 ± 2.2 (mean ± SD) and 13.1 ± 11.2 (mean ± SD) in CM. Median monthly analgesic intake passed from 11.0 (interquartile range [IQR] 10.0-13.0) to 5 (IQR 2.0-8.0) in HFEM and from 20.0 (IQR 15.0-30.0) to 6.0 (IQR 3.8-10.0) in CM. The ≥50% responders were 56.1% (32/57) in HFEM and 75.6% (124/164) in CM; ≥75% responders were 31.6% (18/57) and 44.5% (73/164); and 100% responders were 8.8% (5/57) and 1.2% (2/164), respectively. At Week 48, 83.6% (137/164) of patients with CM had reverted to EM. Erenumab was safe and well tolerated. Responsiveness to erenumab was positively associated with cutaneous allodynia (OR: 5.44, 95% CI: 1.52-19.41; p = 0.009) in HFEM. In patients with CM, ≥50% responsiveness was positively associated with male sex (OR: 2.99, 95% CI: 1.03-8.7; p = 0.044) and baseline migraine frequency (OR: 1.12, 95% CI: 1.05-1.20; p = 0.001) and negatively associated with psychiatric comorbidities (OR: 0.37, 95% CI: 0.15-0.87; p = 0.023) and prior treatment failures (OR: 0.77, 95% CI: 0.64-0.92; p = 0.004). CONCLUSIONS: Long-term (48-week) erenumab treatment provides sustained effectiveness, safety, and tolerability in real-life patients with HFEM or CM with ≥3 prior preventive treatment failures. The dose of 140 mg was required in most patients along the study and should be taken into consideration as the starting dose. Allodynia (in HFEM), male sex, and baseline migraine frequency (in CM) might represent positive responsiveness predictors. Conversely, psychiatric comorbidities and multiple prior preventive treatment failures could be negative predictors in patients with CM.

Clinical features, disease progression, and use of healthcare resources in a large sample of 866 patients from 24 headache centers: A real-life perspective from the Italian chROnic migraiNe (IRON) project.

OBJECTIVE: To develop a dedicated Italian chronic migraine (CM) database (IRON project) to overcome disease misconceptions, improve clinical administration, reduce patients' burden, and rationalize economic resource allotment. BACKGROUND: Proper CM management requires a comprehensive appraisal of its full clinical, social, and economic complexity. METHODS: In this cross-sectional study, CM patients were screened in 24 certified headache centers with face-to-face interviews. Information on sociodemographic factors, medical history, characteristics of CM, and of prior episodic migraine (EM), and healthcare resource use was gathered using a semistructured web-based questionnaire. RESULTS: A total of 866 CM patients were enrolled. CM started ~20 years after EM onset (age at EM onset 17.4 ± 9.1 vs. age at CM onset 35.3 ± 12.5 [mean ± SD]). CM prophylaxis, used by 430/866 (49.6%) of the patients, was often ineffective, not tolerated, and prematurely discontinued. Medications and diagnostic workup, frequently inappropriate, were mostly subsidized by the Italian national health service. CM patients with ≥25 headache days/month revealed substantial clinical differences and heavier disability and economic burden compared with those with <25 headache days/month. CONCLUSIONS: CM is a heterogeneous headache disorder deserving more in-depth clinical characterization, sharper diagnostic criteria, and tailored treatments. CM registries are expected to improve clinical management, resulting in increased disease awareness, better healthcare resource allocation, and reduced economic burden.

Galcanezumab for the prevention of high frequency episodic and chronic migraine in real life in Italy: a multicenter prospective cohort study (the GARLIT study).

BACKGROUND: The clinical benefit of galcanezumab, demonstrated in randomized clinical trials (RCTs), remains to be quantified in real life. This study aimed at evaluating the effectiveness, safety and tolerability of galcanezumab in the prevention of high-frequency episodic migraine (HFEM) and chronic migraine (CM) in a real-life setting. METHODS: This multicenter prospective observational cohort study was conducted between November 2019 and January 2021 at 13 Italian headache centers. Consecutive adult HFEM and CM patients clinically eligible were enrolled and treated with galcanezumab subcutaneous injection 120 mg monthly with the first loading dose of 240 mg. The primary endpoint was the change in monthly migraine days (MMDs) in HFEM and monthly headache days (MHDs) in CM patients after 6 months of therapy (V6). Secondary endpoints were the Numerical Rating Scale (NRS), monthly painkiller intake (MPI), HIT-6 and MIDAS scores changes, ≥50% responder rates (RR), the conversion rate from CM to episodic migraine (EM) and Medication Overuse (MO) discontinuation. RESULTS: One hundred sixty-three patients (80.5% female, 47.1 ± 11.7 years, 79.8% CM) were included. At V6, MMDs reduced by 8 days in HFEM and MHDs by 13 days in CM patients (both p < .001). NRS, MPI, HIT-6 and MIDAS scores significantly decreased (p < .001). Ten patients (6.1%) dropped out for inefficacy and classified as non-responders. Patients with ≥50%RRs, i.e. responders, were 76.5% in the HFEM and 63.5% in the CM group at V6. Among CM patients, the V6 responders presented a lower body mass index (p = .018) and had failed a lower number of preventive treatments (p = .013) than non-responders. At V6, 77.2% of CM patients converted to EM, and 82.0% ceased MO. Adverse events, none serious, were reported in up to 10.3% of patients during evaluation times. CONCLUSIONS: Galcanezumab in real life was safe, well tolerated and seemed more effective than in RCTs. Normal weight and a low number of failed preventives were positively associated with galcanezumab effectiveness in CM patients. TRIAL REGISTRATION: ClinicalTrials.gov NCT04803513 .

Dopaminergic symptoms in migraine: A cross-sectional study on 1148 consecutive headache center-based patients.

BACKGROUND: Dopaminergic symptoms may be extremely pronounced in some migraine patients during the attack, representing a major source of disability. OBJECTIVES: We aimed to carefully characterize the clinical picture of migraine patients with dopaminergic symptoms in a large patients' population as a putative migraine endophenotype, allowing more precise disease management, treatment and outcome prediction. METHODS: We screened 1148 consecutive tertiary care episodic and chronic migraine patients with face-to-face interviews collecting thorough data on lifestyle, socio-demographic factors, and clinical migraine features. RESULTS: We identified 374 patients with migraine with dopaminergic symptoms (32.6%). The most frequent dopaminergic symptom was yawning followed by somnolence, nausea, vomiting, fatigue, mood changes and diuresis. Migraine patients with dopaminergic symptoms had longer attack duration (OR: 1.82; 95% CI: 1.41-2.36, p < 0.0001), more frequent osmophobia (OR: 2.01; 95% CI: 1.50-2.69, p < 0.0001), allodynia (OR: 1.43; 95% CI: 1.10-1.85, p = 0.0071) and unilateral cranial autonomic symptoms (OR: 1.31; 95% CI: 1.01-1.68, p = 0.045), but used less preventative treatments (OR: 0.74; 95% CI: 0.57-0.98, p = 0.033) than patients without dopaminergic symptoms. CONCLUSIONS: Migraine patients with dopaminergic symptoms are characterized by a full-blown, more disabling migraine. Dopaminergic system modulation should be carefully considered in individuals with migraine with dopaminergic symptoms for both acute and preventative treatments in future ad hoc designed studies.

Locking down the CGRP pathway during the COVID-19 pandemic lockdown: the PandeMig study.

OBJECTIVES: The COVID-19 pandemic and the consequent lockdown came as a storm disrupting people's everyday life. This study aimed at observing whether the COVID-19 related lockdown influenced migraine frequency and disability in migraine patients on therapy with monoclonal antibodies inhibiting the CGRP pathway. METHODS: In this longitudinal observational cohort study, 147 consecutive patients receiving monthly administration of erenumab or galcanezumab were enrolled in four Italian headache centers. All patients filled a questionnaire concerning working and household settings, recent flu symptoms or COVID-19 diagnosis, and family loss due to COVID-19 infection. Monthly migraine days (MMDs), monthly painkiller intake (MPI), and HIT-6 disability relative to the first month of lockdown imposition (T-lock) and the month before (T-free) were also collected. RESULTS: From T-free to T-lock, the cohort displayed a reduction in MMDs (from 10.5 ± 7.6 to 9.8 ± 7.6, p = .024) and HIT-6 scores (from 59.3 ± 8.3 men reduced MPI more frequently than women (p = .005). CONCLUSIONS: Our study observed that the lockdown impact to 57.8 ± 8.8, p = .009), while MPI resulted unchanged (from 11.6 ± 11.5 to 11.1 ± 11.7; p = .114). MMDs, MPI, and HIT-6 variations from T-free to T-lock did not differ according to work settings or household. Patients beyond the first 3 months of therapy presented less often a reduction in MMDs (p = .006) and on everyday life did not affect the migraine load in patients receiving monoclonal antibodies inhibiting the CGRP pathway. Patients in the first months of therapy experienced a greater improvement according to drug pharmacokinetics, while women more frequently needed rescue medications, possibly indicating presenteeism or cephalalgophobia.

Does the migraine attack start in the cortex and is the cortex critical in the migraine process?

Migraine is a pure human neurovascular disorder with no reliable corresponding animal model. The cerebral cortex (CC) has long been discussed as a crucial element of its complex mechanism. The present review considers the state of the art of experimental evidence on the involvement of CC in migraine. An ample series of research data points to a role of CC in the migraine process, also at the beginning of the attack, especially in the form with aura. However, in spite of several CC, peculiarities emerged in experimental settings, the enigma on their significance (cause or consequence of the disease?) remains. All in all, we believe that pure clinical observations and reasoning, i.e., its exclusive human nature and the precipitating role of stress, are still the most persuasive cues supporting the CC involvement in migraine.

Dopamine-beta-hydroxylase 19-bp insertion/deletion polymorphism affects medication overuse in patients with chronic migraine.

Dopamine-beta-hydroxylase (DBH) enzyme activity is modulated at the genetic level by the presence of several polymorphisms. Among these, the 19-bp insertion/deletion (I/D) polymorphism (rs72393728/rs141116007) was investigated in several genetic association studies for its correlation with the susceptibility to develop episodic migraine, but conflicting results were achieved. In the present study we analyzed this genetic variant in a carefully characterized population of migraineurs encompassing both episodic and chronic migraine (with and without medication overuse) with the aim to perform a replication study and verify any possible correlation with migraine endophenotypes. Genotyping of the DBH 19-bp I/D polymorphism was performed on 400 migraine patients and 204 healthy individuals. The associations between genotypic frequencies and the clinical and sociodemographic features of migraineurs were then investigated. The DBH 19-bp I/D polymorphism did not correlate with migraine susceptibility or most clinical variables, with the exception of a statistically significant correlation within the subgroup of patients affected by chronic migraine were the individuals carrying the deleted (D) allele were significantly more prone to abuse in analgesics. As a result of this finding, the DBH 19-bp I/D polymorphism does not influence migraine susceptibility, but it might contribute to the development of medication overuse in patient with chronic migraine.

Ketogenic diet in migraine: rationale, findings and perspectives.

Ketogenic diet (KD) is an established treatment for refractory pediatric epilepsy and a promising therapy for diverse neurological diseases. Clinical data on KD in migraine-obtained from 150 patients investigated in case reports and prospective studies-suggest that KD may be a rapid onset effective prophylaxis for episodic and chronic migraine. KD would contribute to restore brain excitability and metabolism and to counteract neuroinflammation in migraine, although its precise mechanism is still unclear. Randomized controlled studies are needed to confirm the usefulness of KD in migraine and to investigate its optimal duration, repeatability, feasibility in normal weight subjects, efficacy in pediatric population and association to conventional migraine prophylaxis.

The role of anti-CGRP antibodies in the pathophysiology of primary headaches.

Calcitonin gene-related peptide (CGRP), a potent vasodilator and pain-signaling neuropeptide, is a validated therapeutic target for migraine and cluster headache. Four anti-CGRP monoclonal antibodies (mAbs) have been developed, representing the first specific, mechanism-based, migraine prophylactic treatment. CGRP mAbs demonstrated good efficacy coupled to excellent tolerability and safety in 5 phase II clinical trials. Notably, CGRP mAbs induced complete migraine remission in a patients' subset. To date, more than 20 phase III trials using CGRP mAbs for of episodic and chronic migraine and cluster headache prevention are ongoing. Future investigations will shed light on migraine endophenotypes predictive of good CGRP mAbs responsiveness and provide answers on their long-term cardiovascular safety.

Look beyond Catechol-O-Methyltransferase genotype for cathecolamines derangement in migraine: the BioBIM rs4818 and rs4680 polymorphisms study.

BACKGROUND: The study of COMT gene polymorphisms in migraine could be of particular interest since impaired catecholaminergic neurotransmission, namely chronic dopaminergic and noradrenergic hypofunction, is a peculiar migraine trait. In this study, for the first time, we focused on the role of COMT rs4818 genetic variant, the polymorphism most strongly affecting COMT activity, in migraine. This study was conducted in a cohort of carefully clinical characterized Caucasian migraineurs recruited in a specifically dedicated migraine biobank, providing also a replication study on rs4680 polymorphism. FINDINGS: Genotyping of rs4680 and rs4818 Catechol-O-Methyltransferase gene polymorphisms was performed on 380 unrelated migraine patients, and 132 healthy subjects matched for age, gender and race-ethnicity, with no clinical evidence or family history of migraine or other neurological diseases. The rs4680 and rs4818 genotypic frequencies did not deviate from those expected for a population in Hardy-Weinberg equilibrium and did not correlate with demographics or clinical migraine features, even when considering migraine subtypes such as dopaminergic migraine, menstrual migraine, and menstrually related migraine . CONCLUSIONS: COMT genotype does not influence migraine susceptibility or phenotype, even considering rs4818 polymorphism and peculiar clinical subtypes. This finding prompts to go over COMT to explain catecholamine derangement in migraine, exploring enzymes involved in catecholamines synthesis and catabolism, such as monoamine-oxidase, dopamine beta-hydroxylase, tyrosine-hydroxylase or tyrosine-decarboxylase, among others.

Headache in chronic cocaine users: A cross-sectional study.

BACKGROUND: Headache is one of the most common symptoms after cocaine use. METHODS: We investigated headache frequency and characteristics and the correlation between headache and acute cocaine intake in a cross-sectional study in a consecutive series of chronic cocaine users. RESULTS: Participation rate was 94.1%. Of the 80 subjects enrolled, 72 (90%) reported current headaches, in most cases migraine or probable migraine without aura. Of these 72, 29 (40.3%) had a headache history, whereas 43 (59.7%) reported de novo headache after beginning to use cocaine. After acute cocaine use, a large percentage of users reported headache attacks: 86.2% of previous headache sufferers (migraine or probable migraine without aura in all cases) and 93% of de novo headache sufferers (migraine/probable migraine without aura = 35; episodic tension-type headache = three patients; cocaine-induced headache= two patients). Most subjects reported that when they used cocaine headaches worsened. CONCLUSION: Chronic cocaine use frequently seems to worsen or induce headache with migraine or migraine-like characteristics, probably owing to a serotoninergic and dopaminergic system impairment. In headache sufferers, especially those with migraine headaches, clinicians should enquire into possible cocaine use.