Negative predictors of clinical response to triptans in patients with migraine

The impact of genetic factors on the response to migraine therapy

Migraine is a multidimensional disease affecting a large portion of the human population presenting with a variety of symptoms. In the era of personalized medicine, successful migraine treatment presents a challenge, as several studies have shown the impact of a patient's genetic profile on therapy response. However, with the emergence of contemporary treatment options, there is promise for improved outcomes. A literature search was conducted in PubMed and Scopus, in order to obtain studies investigating the impact of genetic factors on migraine therapy outcome. Overall, 23 studies were included in the current review, exhibiting diversity in the treatments used and the genetic variants investigated. Divergent genes were assessed for each category of migraine treatment. Several genetic factors were identified to contribute to the heterogeneous response to treatment. SNPs related to pharmacodynamic receptors, pharmacogenetics and migraine susceptibility loci were the most investigated variants, revealing some interesting significant results. To date, various associations have been recorded correlating the impact of genetic factors on migraine treatment responses. More extensive research needs to take place with the aim of shedding light on the labyrinthine effects of genetic variations on migraine treatment, and, consequently, these findings can promptly affect migraine treatment and improve migraine patients' life quality in the vision of precise medicine.

New management strategies for primary headache disorders: Insights from P4 medicine

Primary headache disorder is the main cause of headache attacks, leading to significant disability and impaired quality of life. This disorder is increasingly recognized as a heterogeneous condition with a complex network of genetic, environmental, and lifestyle factors. However, the timely diagnosis and effective treatment of these headaches remain challenging. Precision medicine is a potential strategy based on P4 (predictive, preventive, personalized, and participatory) medicine that may bring new insights for headache care. Recent machine learning advances and widely available molecular biology and imaging data have increased the usefulness of this medical strategy. Precision medicine emphasizes classifying headaches according to their risk factors, clinical presentation, and therapy responsiveness to provide individualized headache management. Furthermore, early preventive strategies, mainly utilizing predictive tools, are critical in reducing headache attacks and improving the quality of life of individuals with headaches. The current review comprehensively discusses the potential application value of P4 medicine in headache management.

Polymorphisms of the Proinflammatory Cytokine Genes Modulate the Response to NSAIDs but Not to Triptans in Migraine Attacks

Migraine is a common neurovascular disorder characterized by recurrent episodes of headache and associated neurological symptoms. At present, a significant portion of patients do not obtain a satisfactory response to acute pain-relieving therapies, including NSAIDs and triptans. In this context, pharmacogenetics plays a key role in the understanding of such a diverse response. In order to investigate whether functional polymorphisms in proinflammatory cytokine genes (IL-1α, IL-1β, IL-1RN; IL-6 and TNF-α) may influence the response to acute treatment, 313 consecutive patients with episodic migraine without aura were enrolled. Pain relief by administration of NSAIDs or triptans for three consecutive migraine attacks was evaluated. We found a significant association between A allele of the TNF-α promoter (−308 A/G) and a lack of efficacy after NSAID administration (p < 0.01, OR 2.51, 95% CI: 1.33 < OR < 4.75 compared to the G allele). Remaining polymorphisms had no significant effect on pain relief. Our study showed that a functional polymorphism in the TNF-α gene significantly modulates the clinical response to NSAID administration in acute attacks. Patients with higher production of the active cytokine during stress showed a significantly lower anti-migraine effect. Our results further support a role for TNF-α in the pathophysiological mechanisms of migraine attack.

Individual differences of maladaptive brain changes in migraine and their relationship with differential effectiveness of treatments

Migraine is a difficult disorder to identify with regard to its pathophysiological mechanisms, and its treatment has been primarily difficult owing to interindividual differences. Substantial rates of nonresponsiveness to medications are common, making migraine treatment complicated. In this review, we systematically analyzed recent studies concerning neuroimaging findings regarding the neurophysiology of migraine. We linked the current imaging research with anecdotal evidence from interindividual factors such as duration and pain intensity of migraine, age, gender, hormonal interplay, and genetics. These factors suggested the use of nonpharmacological therapies such as transcranial magnetic stimulation, transcranial direct current stimulation, and placebo therapy for the treatment of migraine. Finally, we discussed how interindividual differences are related to such nondrug treatments.

CALCA and TRPV1 genes polymorphisms are related to a good outcome in female chronic migraine patients treated with OnabotulinumtoxinA

Background

Some variables have been proposed as predictors of efficacy of OnabotulinumtoxinA in chronic migraine patients, but data available are inconclusive. We aimed to analyse the influence of single nucleotide polymorphisms in the response to OnabotulinumtoxinA.

Methods

We included 156 female patients treated with OnabotulinumtoxinA accordingly to PREEMPT paradigm in three headache units. OnabotulinumtoxinA was offered to patients that had not responded to topiramate and at least one other preventative. Age at first procedure was 43.7 ± 11.8 years (16–74). Patients with a reduction of at least 50% in the number of migraine days after two OnabotulinumtoxinA procedures were considered as responders. We analysed 25 polymorphisms selected for their relevance regarding migraine pathophysiology and their association with migraine according to previously published genome-wide association studies. Genotyping was performed using KASP probes and a LightCycler-480 (Roche-Diagnostics). Allelic, genotypic frequencies and dominance/recesivity hypothesis of the allelic variants were compared between responders and non-responders by Fisher’s exact test.

Results

Response to treatment with OnabotulinumtoxinA was achieved in 120 patients (76,9%). Two polymorphisms showed differences: CALCA rs3781719, where allele C represents 26.9% in responders and 40.9% in non-responders (p = 0.007, OR = 3.11 (1.33–7.26)); and TRPV1 rs222749, where allele A represents 4.17% in responders and 12.5% in non-responders (p = 0.013, OR = 3.29 (1.28–8.43)). No significant differences in rest of polymorphisms or clinical or demographic variables were found.

Conclusions

Polymorphic variations of CALCA and TRPV1 genes might play a role as prognostic markers of efficacy of OnabotulinumtoxinA in chronic migraine female patients in our population.

[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.

Using a Genetic Risk Score Approach to Predict Headache Response to Triptans in Migraine Without Aura

A large meta-analysis of genome-wide association studies has recently identified a number of risk loci for migraine without aura (MwoA). In this study, we tested the hypothesis that a genetic risk score based on single-nucleotide polymorphisms (SNPs), previously reported to be associated with MwoA at genome-wide significance, may influence headache response to triptans in patients with migraine without aura. Genotyping of rs9349379, rs2078371, rs6478241, rs11172113, rs1024905, and rs6724624 was conducted with a real-time PCR allelic discrimination assay in 172 MwoA patients, of whom 36.6% were inconsistent responders to triptans. Each genetic risk score model was constructed as an unweighted score, calculated by adding the number of risk alleles for MwoA across each SNP at selected loci. The association with headache response to triptans was evaluated by logistic regression analysis adjusted for triptan, and the P values were corrected for the false discovery rate. The genetic risk score including susceptibility risk alleles at TRPM8 rs6724624 and FGF6 rs1024905 was found to be inversely associated with risk of inconsistent response to triptans (OR, 0.62; 95%CI, 0.43-0.89; false discovery rate q value, 0.045). In addition, adding this genetic risk score to the triptan-adjusted logistic regression model significantly improved (P = .037) the discrimination accuracy, from 0.57 (95%CI, 0.50-0.65) to 0.64 (95%CI, 0.57-0.72). A modest but significant effect on risk of inconsistent response to triptans was identified for a genetic risk score model composed of 2 known risk alleles for MwoA, suggesting its potential utility in predicting headache response to triptan therapy.

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.

Genetic Polymorphisms in the Dopamine Receptor 2 Predict Acute Pain Severity After Motor Vehicle Collision

OBJECTIVES

Dopaminergic signaling is implicated in nociceptive pathways. These effects are mediated largely through dopamine receptors and modulated in part by dopamine transporters. This study tested the hypothesis that genetic variants in the genes encoding dopamine receptor 2 (DRD2) and the dopamine active transporter (SLC6A3) influence acute pain severity after motor vehicle collision.

MATERIALS AND METHODS

European Americans presenting to the emergency department after motor vehicle collision were recruited. Overall pain intensity in emergency department was assessed using a 0 to 10 numeric rating scale. DNA was extracted from blood samples and genotyping of single-nucleotide polymorphisms (SNPs) in the DRD2 and SLC6A3 gene was performed.

RESULTS

A total of 948 patients completed evaluation. After correction for multiple comparisons, SNP rs6276 at DRD2 showed significant association with pain scores, with individuals with the A/A genotype reporting lower mean pain scores (5.3; 95% confidence interval [CI], 5.1-5.5) than those with A/G (5.9; 95% CI, 5.6-6.1) or G/G (5.7; 95% CI, 5.2-6.2) genotypes (P=0.0027). Secondary analyses revealed an interaction between sex and DRD2 SNPs rs4586205 and rs4648318 on pain scores: females with 2 minor alleles had increased pain intensity, whereas males with 2 minor alleles had less pain than individuals with a major allele (interaction P=0.0019).

DISCUSSION

Genetic variants in DRD2 are associated with acute pain after a traumatic stressful event. These results suggest that dopaminergic agents may be useful for the treatment of individuals with acute posttraumatic pain as part of a multimodal opioid-sparing analgesic regimen.

Pharmacogenomics of episodic migraine: time has come for a step forward

Migraine is characterized by heterogeneous behavior in response to drugs. Many resources have been invested in attempting to unravel the genetic basis of migraine, while the role of genetics in responses to currently available drugs has received less attention. We performed a systematic literature search identifying original articles pertaining to pharmacogenomics of episodic migraine. Few primary studies on the pharmacogenomics of symptomatic and preventive medication in episodic migraine were found. The number of patients studied in the individual articles ranged from 40 up to 130. There was a strong heterogeneity among these studies. We believe that pharmacogenomics studies, if properly designed, could contribute towards optimizing the treatment and reducing the burden of migraine, in turn helping patients and optimizing resources. Our knowledge on the pharmacogenomics of migraine is growing too slowly, and concerted measures should be undertaken to speed up the process.

Characteristics of inconsistent responders to prophylaxis therapy with lomerizine in patients with migraine: a retrospective study in Japan

Although lomerizine is used as a first-line prophylactic drug for migraines in Japan, approximately 30% of patients fail to respond to this treatment. On the basis of medical records, we investigated the involvement of clinical factors in response to lomerizine used in patients with migraine as primary headache and established a scoring system for predicting clinical responses to prophylactic therapy. Ninety-four consistent responders and 33 inconsistent responders to lomerizine were enrolled in this study. Multivariate stepwise logistic regression analysis revealed that migraine plus tension-type headache as primary headache and frequency of headache attacks were significant factors that contributed independently to negative response [odds ratio, 3.817 (no vs. yes; 95% confidence interval (CI), 1.264-11.628) and 5.814 (>15 episode days/month vs. 0-14 episode days/month; 95% CI, 2.381-14.286), respectively]. The predictive index (PI) of clinical responses to lomerizine in patients with migraine was calculated using the regression coefficients of two factors as an integer, where the score for inconsistent responders (1.00±0.71) was significantly higher than that for consistent responders (0.37±0.53, p<0.001). Sensibility of the low-scoring group (PI=0) was 75.8%, and specificity of the high-scoring group (PI=2) was 97.9%. Groups scoring low, intermediated and high included 11.6%, 35.4% and 80.0% of inconsistent responders, respectively. The PI value obtained might represent an appropriate scoring system to predict responses in these patients.

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

Migraine patients are particularly prone to develop medication overuse headache (MOH). However, the risk factors for the transformation of migraine to MOH are still not clear. We investigated gene polymorphisms, personality traits, and characteristics of headache and lifestyle in 47 migraine patients (aged 36.4 ± 10.3) and 22 MOH patients (aged 39.6 ± 9.9) who progressed from migraine and made a scoring system for a predictive index (PI) of the onset of MOH in patients with migraine. By multivariate logistic stepwise regression analysis, type of migraine, regular and sufficient dietary intake, and methylenetetrahydrofolate reductase (MTHFR) C677T (rs1801133) and dopamine D2 receptor (DRD2) C939T (rs6275) polymorphisms were selected as significant factors that contribute independently to the development from migraine to MOH (P < 0.05). The regression coefficients (β) of these four selected factors were approximated and scored. The PI score in MOH patients (7.32 ± 1.60) was significantly higher than that in migraine patients (4.62 ± 1.83, P < 0.001). The proposed scoring system should in the future be the object of larger studies to confirm its validity.