Predictive index for the onset of medication overuse headache in migraine patients

[Therapeutic Effects of Intranasal Sumatriptan for Cluster Headache]

To clarify the associated factors for negative response to sumatriptan nasal spray in patients with cluster headache, we investigated the involvement of clinical information, such as the characteristics of headaches, before commencing sumatriptan nasal spray treatment. There were 18 male patients and 4 female patients. A total of 17 responders and 5 non-responders to sumatriptan nasal spray participated in the present study. Three factors for negative response to sumatriptan nasal spray, "young age of onset", "psychiatric disorder", and "the headache is not in the orbit," were found. Oxygen inhalation and/or subcutaneous injection were effective for nonresponsive cases. Therefore, these factors are considered to be useful for predicting therapy before applying sumatriptan nasal spray.

Development of an AmpliSeqTM Panel for Next-Generation Sequencing of a Set of Genetic Predictors of Persisting Pain

Background: Many gene variants modulate the individual perception of pain and possibly also its persistence. The limited selection of single functional variants is increasingly being replaced by analyses of the full coding and regulatory sequences of pain-relevant genes accessible by means of next generation sequencing (NGS).

Methods: An NGS panel was created for a set of 77 human genes selected following different lines of evidence supporting their role in persisting pain. To address the role of these candidate genes, we established a sequencing assay based on a custom AmpliSeq^TM panel to assess the exomic sequences in 72 subjects of Caucasian ethnicity. To identify the systems biology of the genes, the biological functions associated with these genes were assessed by means of a computational over-representation analysis.

Results: Sequencing generated a median of 2.85 ⋅ 10⁶ reads per run with a mean depth close to 200 reads, mean read length of 205 called bases and an average chip loading of 71%. A total of 3,185 genetic variants were called. A computational functional genomics analysis indicated that the proposed NGS gene panel covers biological processes identified previously as characterizing the functional genomics of persisting pain.

Conclusion: Results of the NGS assay suggested that the produced nucleotide sequences are comparable to those earned with the classical Sanger sequencing technique. The assay is applicable for small to large-scale experimental setups to target the accessing of information about any nucleotide within the addressed genes in a study cohort.

The role of personality, disability and physical activity in the development of medication-overuse headache: a prospective observational study

Background

Factors associated with development of medication-overuse headache (MOH) in migraine patients are not fully understood, but with respect to prevention, the ability to predict the onset of MOH is clinically important. The aims were to examine if personality characteristics, disability and physical activity level are associated with the onset of MOH in a group of migraine patients and explore to which extend these factors combined can predict the onset of MOH.

Methods

The study was a single-center prospective observational study of migraine patients. At inclusion, all patients completed questionnaires evaluating 1) personality (NEO Five-Factor Inventory), 2) disability (Migraine Disability Assessment), and 3) physical activity level (Physical Activity Scale 2.1). Diagnostic codes from patients’ electronic health records confirmed if they had developed MOH during the study period of 20 months. Analyses of associations were performed and to identify which of the variables predict onset MOH, a multivariable least absolute shrinkage and selection operator (LASSO) logistic regression model was fitted to predict presence or absence of MOH.

Results

Out of 131 participants, 12 % (n=16) developed MOH. Migraine disability score (OR=1.02, 95 % CI: 1.00 to 1.04), intensity of headache (OR=1.49, 95 % CI: 1.03 to 2.15) and headache frequency (OR=1.02, 95 % CI: 1.00 to 1.04) were associated with the onset of MOH adjusting for age and gender. To identify which of the variables predict onset MOH, we used a LASSO regression model, and evaluating the predictive performance of the LASSO-mode (containing the predictors MIDAS score, MIDAS-intensity and –frequency, neuroticism score, time with moderate physical activity, educational level, hours of sleep daily and number of contacts to the headache clinic) in terms of area under the curve (AUC) was weak (apparent AUC=0.62, 95% CI: 0.41-0.82).

Conclusion

Disability, headache intensity and frequency were associated with the onset of MOH whereas personality and the level of physical activity were not. The multivariable LASSO model based on personality, disability and physical activity is applicable despite moderate study size, however it can be considered as a weak classifier for discriminating between absence and presence of MOH.

Association of expression of DRD2 rs1800497 polymorphism with migraine risk in Han Chinese individuals

Background

Previous studies suggested that single-nucleotide polymorphisms in dopamine receptor D2 (DRD2) are the susceptibility loci for migraine. This study was aimed at evaluating the contribution of DRD2 rs1800497 and its expression to migraine risk in Han Chinese subjects.

Methods

In total, 250 patients with migraine and 250 age- and sex-matched control subjects were included in this study. TaqMan allelic discrimination assay was used for DRD2 rs1800497 genotyping. Plasma DRD2 concentration was determined using enzyme-linked immunosorbent assay.

Results

Significant associations were observed for the rs1800497 genotype (c²=6.37, p=0.041) and allele (c²=4.69, p=0.03; odds ratio [OR]=1.33, 95% CI=1.03-1.72, power=58%) frequencies between the migraine and control groups. Sex analysis indicated a positive association for rs1800497 between female patients with migraine and control individuals (genotype: c²=7.84, p=0.019; allele: c²=6.60, p=0.010; OR=1.61, 95% CI=1.12-2.30, power=73.4%). Furthermore, a significant association was observed only in female patients with migraine without aura (MO) (genotype: c²=6.88, p=0.032; allele: c²=5.65, p=0.017; OR=1.59, 95% CI=1.08-2.36, power=65.1%). The mean plasma DRD2 levels in the control group (mean±SD: 24.20±2.78) were significantly lower than those in the migraine with aura (MA) (30.86±3.69, p<0.0001) and MO groups (31.88±4.99, p<0.0001). Additionally, there was a sex-based difference in DRD2 expression in the MA (male vs female: 29.46±3.59 vs 32.27±3.27, p<0.01) and MO groups (male vs female: 29.18±3.50 vs 34.58±4.84, p<0.0001). Moreover, plasma DRD2 levels in patients were significantly different among the three genotypes (CC vs CT vs TT: 24.76±3.76 vs 30.93±3.85 vs 37.06±3.95, p<0.0001). Similar results were observed both in the MA (CC vs CT vs TT: 25.09±3.84 vs 28.57±2.84 vs 33.37±1.58, p<0.0001) and MO groups (CC vs CT vs TT: 24.65±3.79 vs 31.65±3.86 vs 38.29±3.74, p<0.0001).

Conclusion

Our case-control study suggested that the DRD2 polymorphism rs1800497 was significantly associated with the risk of migraine in Han Chinese females. Additionally, the plasma DRD2 level was high in patients with migraine. Females with migraine had considerably higher DRD2 levels than males with migraine. DRD2 expression may be regulated by DRD2 rs1800497 genotype in patients with migraine.

A systematic review and critical appraisal of gene polymorphism association studies in medication-overuse headache

Purpose of review

Medication-overuse headache is a secondary chronic headache disorder, evolving from an episodic primary headache type, caused by the frequent and excessive use of headache symptomatic drugs. While gene polymorphisms have been deeply investigated as susceptibility factors for migraine, little attention has been paid to medication-overuse headache genetics. In the present study we conducted a systematic review to identify, appraise and summarize the current findings of gene polymorphism association studies in medication-overuse headache.

Methods

A comprehensive literature search was conducted on PubMed and Web of Knowledge databases of primary studies that met the diagnostic criteria for medication-overuse headache according to the temporally-relevant Classification of Headache Disorder of the International Headache Society.

Results

A total of 17 candidate gene association studies focusing on medication-overuse headache were finally included in the qualitative review. Among these, 12 studies investigated the role of common gene polymorphisms as risk factors for medication-overuse headache susceptibility, six studies focused on the relationship with clinical features of medication-overuse headache patients, and four studies evaluated their role as determinants of clinical outcomes in medication-overuse headache patients.

Conclusion

Results of single studies show a potential role of polymorphic variants of the dopaminergic gene system or of other genes related to drug-dependence pathways as susceptibility factors for disease or as determinants of monthly drug consumption, respectively. In this systematic review, we summarize the findings of gene polymorphism association studies in medication-overuse headache and discuss the methodological issues that need to be addressed in the design of future studies.

Clinical Response to Valproate in Patients with Migraine

Background and Purpose

Valproate is used as a prophylactic drug for migraine, but it is not be effective in all patients. We used medical records to investigate which clinical factors affected the response to valproate in patients with migraine as an original headache, and established a scoring system for predicting the clinical response to prophylactic therapy.

Methods

We investigated clinical factors from the medical records of 95 consistent responders (CRs) and 24 inconsistent responders (IRs) to valproate.

Results

Multivariate stepwise logistic regression analysis revealed that a history of hyperlipidemia and hay fever and the complication of depression or other psychiatric disorder were significant factors that independently contributed to a negative response, with odds ratios of 6.024 [no vs. yes; 95% confidence interval (CI)=1.616–22.222], 2.825 (no vs. yes; 95% CI=1.046–7.634), and 2.825 (no vs. yes; 95% CI=1.052–7.576), respectively. A predictive index (PI) of the clinical response to valproate in patients with migraine was calculated using the regression coefficients of these three factors as an integer, and the index was significantly higher for IRs than for CRs (1.46±1.10 vs. 0.69±0.74, mean±SD, p<0.001).

Conclusions

The obtained PI may represent an appropriate scoring system for predicting the responses in these patients.

Medication overuse headache

Medication overuse headache (MOH) is a common and disabling headache disorder. It has a prevalence of about 1-2 % in the general population. The International Classification of Headache Disorders 3rd edition (beta version) has defined MOH as a chronic headache disorder in which the headache occurs on 15 or more days per month due to regular overuse of medication. These headaches must have been present for more than 3 months. The pathophysiology is complex and not completely known. It involves genetic and behavioural factors. There is evidence that cortical spreading depression, trigeminovascular system and neurotransmitters contribute to the pain pathway of MOH. The treatment of MOH includes patient education, stopping the offending drug(s), rescue therapy for withdrawal symptoms and preventative therapy. Relapse rates for MOH are high at 41 %. MOH can severely impact quality of life, so it is important to identify patients who are at risk of analgesic overuse.