Pathogenesis of migraine

Metabolic syndrome and components exacerbate osteoarthritis symptoms of pain, depression and reduced knee function

BACKGROUND

The purpose of this study was to investigate the prevalence of metabolic syndrome and its co-morbidities in patients with primary knee osteoarthritis and to assess if the severity of metabolic syndrome, and components, correlates with the severity of osteoarthritis symptoms.

METHODS

A case controlled analysis of 70 patients with osteoarthritis compared to a control group of 81 patients. Each patient underwent clinical review including history, examination, and pathology tests. The case-group all had stage IV osteoarthritis as determined by radiographs and intra-operative assessment. In addition a visual analogue scale (VAS), Hospital for Special Surgery knee score (HSS), and Hamilton Depression scores were completed.

RESULTS

The prevalence of hypertension, obesity, dyslipidemia and metabolic syndrome was significantly higher in the patients with osteoarthritis compared to the control group. There is a significant correlation between the degree of hypertension, the presence of dyslipidemia or hyperglycemia and the severity of osteoarthritis symptoms. Variables hypertension, low HDL-C levels, and the number of co-morbidities were all identified as risk factors for increased osteoarthritis symptoms.

CONCLUSIONS

There is a correlation between the number of metabolic disorders, the severity of hypertension and severity of osteoarthritis symptoms. Hypertension and decreased HDL-cholesterol were positive risk factors for increased osteoarthritis symptomatology.

Is Helicobacter pylori infection a risk factor for childhood periodic syndromes?

Background and objectives

Helicobacter pylori (H. pylori) infection has been assumed to have roles in various extra-digestive diseases. The current study was designed to evaluate the incidence of H. pylori infection in patients with cyclic vomiting syndrome and its possible role in the etiology of this disease.

Design and setting

In this case-control study, 120 cases with diagnoses of cyclic vomiting or abdominal migraine who were registered at the Gastroenterology Clinic at Shiraz University of Medical Sciences from 2010 to 2013 were enrolled.

Materials and methods

Primarily information regarding the patients' diseases were collected with a data gathering sheet, and fresh morning stool samples were collected from the patients and examined for H. pylori stool antigen with the H. pylori Ag EIA test kit. The results were compared with those of healthy children from the control group.

Results

A total of 120 patients with cyclic vomiting (47.5%) and abdominal migraine (52.5%) with a mean age of 7.1 ± 3.4 (range 2-16 years) and a male-to-female ratio of 1.6 were included. The HPs Ag tests were positive in only 7 (5.8%) patients in our case group, and the HPs Ag tests were positive in 13 (13%) of the children in the control group; this difference was statistically insignificant.

Conclusion

Our study did not support H. pylori infection as an etiological factor in CV or AM.

Endothelial Function in Patients with Migraine without Aura during the Interictal Period

Background:

In most of the studies, the association of vascular events is limited to migraine with aura or it is stronger in this group, whereas the link between migraine without aura (MO) and vascular events remained uncertain. Therefore, we decided to evaluate endothelial function by chemical and functional markers of endothelium in MO and compare with normal population.

Methods:

In this study, 39 patients and 25 healthy subjects were enrolled and flow-mediated dilatation (FMD), C-reactive protein (CRP), nitrite and nitrate were measured in these two groups.

Results:

The mean of FMD in healthy people was higher than the migraine patients (mean difference − 7.67%; 95% confidence interval [CI] −9.90-−5.44). The means of nitrite concentration in migraineurs was significantly lower than healthy subjects (mean difference − 2.0 μmol/L; 95% CI − 3.45-−0.54). But the CRP concentrations in both groups were not significantly different (mean difference 0.42 pmol/L; 95% CI − 0.13-0.98).

Conclusions:

This study can show the endothelial dysfunction in migraineurs without aura and suggest that MO could also be a risk for cardiovascular disease.

Endothelial function in migraine: a cross-sectional study

Background

Migraine has been associated with cardiovascular disorders. Endothelial dysfunction may be a mechanism underlying this association. The present study tested the hypothesis that endothelium-dependent vasodilation, basal endothelial nitric oxide release and endothelial fibrinolytic capacity are impaired in migraine patients.

Methods

Graded doses of sodium nitroprusside (SNP, 0.2 to 0.8 μg.min^-1.dL^-1 forearm), substance P (0.2 to 0.8 pmol.min^-1.dL^-1 forearm) and N^G-monomethyl-L-arginine (L-NMMA, 0.1 to 0.4 μmol.min^-1.dL^-1 forearm) were infused into the brachial artery of 16 migraine patients with or without aura during a headache-free interval and 16 age- and sex-matched subjects without a history of migraine. Forearm blood flow (FBF) was measured by strain-gauge venous occlusion plethysmography. Local forearm release of tissue plasminogen activator (t-PA) in response to substance P infusion was assessed using the arteriovenous plasma concentration gradient. Responses to infused drugs were compared between patients and matched controls by analysis of variance.

Results

In both migraine patients and control subjects, SNP and substance P caused a dose-dependent increase, and L-NMMA a dose-dependent decrease in FBF (P < 0.001 for all responses). In both groups, substance P caused an increase in t-PA release (P < 0.001). FBF responses and t-PA release were comparable between migraine patients and control subjects.

Conclusions

The absence of differences in endothelium-dependent vasodilation, basal endothelial nitric oxide production and stimulated t-PA release between migraine patients and healthy control subjects argues against the presence of endothelial dysfunction in forearm resistance vessels of migraine patients.

Increased vulnerability to oxidative stress in pediatric migraine patients

Little is known about the role of oxidative stress in the pathogenesis of pediatric migraine. The objective of the present study was to investigate, during a headache-free period, the activities of erythrocyte antioxidant enzymes in children and adolescents diagnosed with migraine. In all, 47 migraine patients (age range, 8-17 years; mean, 14.1 +/- 2.4 years, 14 with aura) and 35 control subjects were included. Superoxide dismutase, glutathione peroxidase, and catalase activities were measured in erythrocytes. Although superoxide dismutase activities did not differ between groups, both catalase and glutathione peroxidase activities were significantly lower in migraine patients (P = 0.001 and P = 0.009, respectively). Activities of all three antioxidant enzymes were similar across migraine subgroups; there was no correlation with age and sex. These results confirm vulnerability to oxidative stress in pediatric migraine. Further studies and search for new therapeutic agents with antioxidant properties are needed.

No arguments for increased endothelial nitric oxide synthase activity in migraine based on peripheral biomarkers

OBJECTIVES

To assess whether migraine patients display a chronic nitric oxide synthase (NOS) hyperactivity by comparing the nitric oxide (NO) production before and following a loading dose of L-arginine between migraine patients (interictally) and matched healthy control subjects. In addition, we evaluated whether a loading dose of L-arginine triggers an acute migraine headache in migraineurs.

SUBJECTS AND METHODS

Twenty healthy subjects and 20 migraine patients participated in a 2-period, randomised, double-blind, placebo-controlled study. Each subject received a 30-min infusion, by peripheral vein, of 30 g L-arginine hydrochloride or placebo (i.e. an equal volume of 0.9% saline solution). Meanwhile, biomarkers associated with the L-arginine-NO pathway (i.e. exhaled NO/nasal NO), plasma citrulline and urinary excretion of nitrite/nitrate and cGMP were assessed before and for 6 h following the start of the infusion.

RESULTS

At baseline, exhaled NO and nasal NO were higher in migraineurs compared to healthy subjects (mean±95% confidence interval): 15.9 (8.8, 23.0) parts per billion (ppb) versus 10.8 (7.0, 14.5) ppb for exhaled NO (P=0.04) and 76.3 (61.2, 91.4) versus 61.6 (51.2, 72.0) ppb for nasal NO (P=0.03), respectively. The AUC0-6 in ppb for exhaled NO and nasal NO following L-arginine or saline infusion did not differ between both groups. The increase in L-citrulline, following L-arginine infusion, was smaller in migraine patients (15 (13, 18) µmol/l) compared to healthy volunteers (19 (16, 23) µmol/l; P=0.046). In healthy subjects, both nitrate and cGMP excretion were higher following L-arginine compared to placebo infusion: 132.63 (100.24, 165.02) versus 92.07 (66.33, 117.82) µmol/mmol creatinine for nitrate (P=0.014) and 50.53 (42.19, 58.87) versus 39.64 (33.94, 45.34) nmol/mmol creatinine for cGMP (P=0.0003), respectively. In migraineurs, excretion of these biomarkers was comparable following L-arginine or saline infusion.

CONCLUSIONS

The results of the present study do not support the idea of a generalised increase in NO synthase activity in migraine patients outside of a migraine attack. The smaller increase in plasma L-citrulline, urinary nitrate and cGMP excretion following L-arginine infusion in migraine patients might indicate dysfunction of endothelial NO synthase.

Forearm vascular response to nitric oxide and calcitonin gene-related peptide: comparison between migraine patients and control subjects

The forearm vascular response to nitric oxide (NO) and calcitonin gene-related peptide (CGRP) was investigated in 10 migraine patients and 10 matched control subjects. Changes in forearm blood flow (FBF) during intrabrachial infusion of: (i) serotonin (releasing endogenous NO), (ii) sodium nitroprusside (SNP, exogenous NO-donor), and (iii) CGRP were measured using venous occlusion plethysmography. Flow-mediated dilation (FMD) of the brachial artery, a measure for the endogenous release of NO reactive to occlusion, was measured using ultrasound and expressed as percentage change vs. baseline diameter. FBF ratio (i.e. FBF in the infused over the control arm) at baseline (1.1 +/- 0.1) did not differ between both populations. Serotonin, SNP and CGRP induced a dose-dependent increase (P < 0.001) in FBF ratio in controls (to 2.8 +/- 0.3, 6.7 +/- 1.4 and 6.9 +/- 1.2 at the highest dose, respectively) and migraineurs (2.5 +/- 0.4, 5.6 +/- 0.8 and 6.5 +/- 1.3, respectively); these ratios did not differ between both groups. FMD was comparable in control subjects (5.8 +/- 1%) and migraine patients (5.2 +/- 1%). Based on the forearm vascular response to NO and CGRP, migraine patients do not display generalized changes in vascular function.

Migraine and Raynaud phenomenon: possible late complications of Kawasaki disease

Migraine and Raynaud phenomenon often coexist and may reflect similar vascular reactions. Both have been associated with vascular endothelial cell dysfunction. Kawasaki disease is a systemic vasculitis of unknown etiology that affects children and may lead to the formation of coronary artery aneurysms. Endothelial cell dysfunction has been demonstrated late in Kawasaki disease and is not restricted to coronary vessels. We report the case of a patient who developed typical migraine with aura and Raynaud phenomenon at the age of 14, 12 years after onset of Kawasaki disease. His migraine responded well to pizotifen, and both migraine and Raynaud phenomenon improved after initiation of treatment with valproic acid. We postulate that both migraine and Raynaud phenomenon in this case represent late consequences of Kawasaki disease and result from extracoronary endothelial dysfunction.

Simultaneous monitoring of endothelin-1 and vasopressin plasma levels in migraine

Vasopressin levels in plasma rise during migraine attacks. Vasopressin also induces endothelin-1 synthesis in endothelial cells, suggesting a role as a mediator of elevated plasma endothelin-1 in migraine. To explore a possible relationship between endothelin-1 and vasopressin in migraine, plasma concentrations of both peptides were monitored simultaneously throughout an attack and during two migraine-free intervals (control) in 20 patients. Endothelin-1 was elevated 6 h after the onset of an attack (3.3 +/- 0.3 pg/ml vs 2.7 +/- 0.2 pg/ml during migraine-free intervals; p = 0.12) whereas vasopressin was increased over control levels (2.8 +/- 0.3 pg/ml) by 3 h (3.6 +/- 0.4 pg/ml; p < 0.05) and remained elevated at 6 h (3.9 +/- 0.5 pg/ml; p < 0.01). These data suggest that vasopressin may act as a peripheral mediator of increased plasma endothelin-1 in migraine.

The pharmacodynamics of sumatriptan in nitroglycerin-induced headache

Migraine is a common disorder that causes significant morbidity in those afflicted. Many novel antimigraine compounds are in clinical development, yet full characterization of each one's pharmacodynamic behavior is a formidable task due to the difficulty in studying a migraineur during an attack. Nitroglycerin (NTG) administration commonly causes a headache with some features similar to those of a migraine. As such, NTG has been used as a model of vascular headaches, including migraine. The pharmacodynamic effects of nitroglycerin and sumatriptan on middle cerebral artery blood flow velocity (MCAv) and headache scores were studied in 10 healthy male volunteers. An intravenous infusion of NTG titrated to 0.5 mcg/kg/min over 30 minutes resulted in a median reduction from baseline in MCAv of 27% (range: 16.4%-37.3%). Nine of the subjects developed a headache with a median verbal score of 3.5 of 10 (range: 0-5). Subjects received sumatriptan either 2 mg intravenously or 6 mg subcutaneously, which abated clinical headache in 9 of the 10 subjects (p = 0.030). A median sumatriptan-induced increase in MCAv of 21% (p = 0.054) suggested a constricting effect on the NTG-induced dilated MCA. A two-compartment pharmacokinetic/indirect-effects pharmacodynamic model was fit to the sumatriptan concentration and MCAv data using iterative two-stage analysis. This model was unbiased and fit the concentration (r2 = 0.98) and the MCAv (r2 = 0.79) data well. These results suggest that NTG-induced headache and the development of pharmacokinetic/pharmacodynamic models could serve as a useful method for exploring the mechanisms of abortive migraine drugs.

Ketorolac as a rapid and effective treatment of migraine headache: evaluations by patients

The objective of this study was to determine the speed and efficiency of ketorolac in reducing the symptoms of migraine headache. Twenty-three patients who presented in the emergency department during the period between April and July 1992 with a previous diagnosis of migraine headache were considered for the study. Patients subjectively evaluated parameters of their migraine headaches (eg, pain and nausea) with a numerical scale and were asked to re-evaluate these same parameters at 30, 60, and 360 minutes after a single injection of Ketorolac. Seventeen (74%) patients reported a decrease in headache symptoms that was significant (P < .005) after 1 hour. Relief lasted at least 6 hours after injection.

Ketorolac versus meperidine and hydroxyzine in the treatment of acute migraine headache: a randomized, prospective, double-blind trial

STUDY OBJECTIVE

To compare the effectiveness of IM ketorolac with that of meperidine and hydroxyzine in the treatment of acute migraine headache.

DESIGN

Prospective, randomized, double-blind trial.

SETTING

Urban emergency department with an annual census of 42,000 patients.

PARTICIPANTS

Forty-seven adult patients with migraines enrolled on 50 visits.

INTERVENTIONS

Patients were randomly assigned to receive a single injection of either 60 mg ketorolac (group 1) or 100 mg meperidine and 50 mg hydroxyzine (group 2). Pain assessment was made using both visual-analog and verbal descriptor scales.

RESULTS

At 60 minutes, 15 patients (60%) from group 1 (25) and 14 patients (56%) from group 2 (25) reported a great deal of complete relief (P = .77) Sixty-minute mean pain relief scores (3.35 versus 3.37) were different (P = .76). Nine patients (36%) from group 1 and seven patients (28%) from group 2 required additional analgesia (P = .76).

CONCLUSION

Ketorolac is as effective as meperidine and hydroxyzine for the treatment of acute migraine headache.