Chronic migraine and medication overuse

Lack of association between TRPV1 gene polymorphisms and risk of migraine chronification: a case-control study and meta-analysis

OBJECTIVE

To confirm a previously reported association of TRPV1 rs8065080 with the risk of transformation from episodic (EM) to chronic migraine (CM) and to extend knowledge about the role of other TRPV1 single nucleotide polymorphisms (SNPs), we first investigated the impact of three TRPV1 SNPs (rs8065080, rs222747 and rs222749) on the risk of migraine chronification in a case-control study. A systematic review and meta-analysis were then conducted to summarize the accumulated findings.

METHODS

Genotyping of the selected TRPV1 SNPs was performed using TaqMan real-time PCR in 167 EM and 182 CM participants. Crude and adjusted odds ratios with associated 95% confidence intervals were calculated in the log-additive, dominant, and recessive genetic models. A comprehensive literature search was performed in PubMed, Web of Knowledge, Cochrane Library, and OpenGrey until February 2024.

RESULTS

In our case-control study, no association was found between TRPV1 SNPs and the risk of migraine chronification, both in the unadjusted logistic regression models and after adjustment for confounding clinical variables. The results of the meta-analysis with a total of 241 participants with EM and 223 with CM confirmed no association between TRPV1 SNPs and the risk of migraine chronification in any of the genetic models tested.

CONCLUSION

The results of the present case-control study and meta-analysis exclude a major role of TRPV1 rs8065080, rs222747, and rs222749 as risk factors for migraine chronification. However, further research is needed to investigate the gene-gene and gene-environment interactions of TRPV1 SNPs on the risk of transformation from episodic to chronic migraine.

Calcitonin gene-related peptide-targeting therapies are a first-line option for the prevention of migraine: An American Headache Society position statement update

OBJECTIVE

To provide a position statement update from The American Headache Society specifically regarding therapies targeting calcitonin gene-related peptide (CGRP) for the prevention of migraine.

BACKGROUND

All migraine preventive therapies previously considered to be first-line treatments were developed for other indications and adopted later for migraine. Adherence to these therapies is often poor due to issues with efficacy and tolerability. Multiple new migraine-specific therapies have been developed based on a broad foundation of pre-clinical and clinical evidence showing that CGRP plays a key role in the pathogenesis of migraine. These CGRP-targeting therapies have had a transformational impact on the management of migraine but are still not widely considered to be first-line approaches.

METHODS

Evidence regarding migraine preventive therapies including primary and secondary endpoints from randomized placebo-controlled clinical trials, post hoc analyses and open-label extensions of these trials, and prospective and retrospective observational studies were collected from a variety of sources including PubMed, Google Scholar, and ClinicalTrials.gov. The results and conclusions based upon these results were reviewed and discussed by the Board of Directors of The American Headache Society to confirm consistency with clinical experience and to achieve consensus.

RESULTS

The evidence for the efficacy, tolerability, and safety of CGRP-targeting migraine preventive therapies (the monoclonal antibodies: erenumab, fremanezumab, galcanezumab, and eptinezumab, and the gepants: rimegepant and atogepant) is substantial, and vastly exceeds that for any other preventive treatment approach. The evidence remains consistent across different individual CGRP-targeting treatments and is corroborated by extensive "real-world" clinical experience. The data indicates that the efficacy and tolerability of CGRP-targeting therapies are equal to or greater than those of previous first-line therapies and that serious adverse events associated with CGRP-targeting therapies are rare.

CONCLUSION

The CGRP-targeting therapies should be considered as a first-line approach for migraine prevention along with previous first-line treatments without a requirement for prior failure of other classes of migraine preventive treatment.