Prevention of chronic migraine in New Zealand
By Dr Fiona Imlach, MBChB, PhD Co-founder of Migraine Foundation Aotearoa New Zealand
19 September 2022
For a disease that affects an estimated 642,000 people in Aotearoa New Zealand, and is the fourth largest cause of disability, migraine gets very little attention. It’s not mentioned in any strategies from the Ministry of Health and the last published data on prevalence was from 2006/07. This is why the estimate of 642,000 people comes from the 2019 Global Burden of Disease (1) which is useful, but leaves us with no idea of the number of Māori or Pasifika people affected or how people are accessing health services.
We also estimate that 45,000 people in Aotearoa New Zealand have chronic migraine, based on international data that this occurs in around 7-8% of people with migraine, and 1-2 percent of the population. Chronic migraine is defined as 15 or more headache days a month (at least 8 with typical migraine features) and is associated with high levels of disability, often meaning that people struggle to remain in employment.
"Most days I have brain fog, trouble finding words/getting them out in the right order, focusing my eyes on anything, focusing on work. I feel like I am a grape that has had every last bit of juice sucked out of me and I am shrivelled! My Grandad who is aged 97 has more cognitive energy than me." Suzanne, Canterbury.
Most patients with chronic migraine start out with episodic migraine (migraine attacks on 14 days or fewer per month) and around three percent of people with episodic migraine develop chronic migraine per year. Overuse and/or ineffective use of acute migraine medication can lead to chronic migraine, and it is linked to obesity, depression and stressful life events. (2) Clinical features that predict progression to chronic migraine include a higher monthly headache frequency, cutaneous allodynia and persistent nausea. (3)
After the birth of my second child, my migraine attacks became more chronic and I started to try more migraine-specific medications. Preventative medications didn’t decrease the attacks enough, and some of the medicines were too hard on my stomach as I suffered from gastric ulcers in my 20s.
By age 39, I was taking way too many NSAIDs and triptans to be healthy. I also ended up in the hospital every three months or so because of week-long episodes that just wouldn’t respond to treatment. Mara, Auckland
In general practice, the most important ways to prevent chronic migraine are to ensure that acute attacks are treated quickly and effectively, and to instigate preventive treatment. Preventives should be considered in patients having four or more migraine attacks a month, intolerance or contraindication to acute treatment, and medication overuse. (4) Medication overuse can cause daily headache in people with migraine who have been taking triptans, opioids, or combination analgesics for 10 days or more per month, or simple analgesics for 15 days or more per month. (5) Management involves the reduction or withdrawal of the overused medication.
Chronic migraine is reversible. Besides preventive medications, treatment options include onabotulinum toxin-A injections (not funded), occipital nerve blocks (6) and neuromodulation (supra-orbital transcutaneous electrical nerve stimulation devices are available in New Zealand). (7)
Current issues with standard preventive medications include the relatively low efficacy (around half of patients achieve a 50 percent reduction in migraine attacks), poor tolerability due to adverse effects and safety concerns (e.g. valproate in women of child-bearing age). (8,9) Efficacy also tends to wane over time. New preventive treatments developed specifically for migraine target calcitonin gene-related peptide, a small protein involved in the pathogenesis of migraine attacks. These are generally well-tolerated, with relatively few side effects, and similar efficacy to older preventives, although they appear to be more effective in treating medication overuse and patients who have not had success with other preventives.
Managing migraine, particularly chronic migraine, can be challenging, as demonstrated by the quotes in this piece from real patient stories. Migraine Foundation Aotearoa New Zealand is a charity that aims to raise awareness and support people living with migraine in New Zealand. In our online support group, people are encouraged and realise they are not alone. Through evidence-based information on the causes of migraine, acute and preventive migraine treatments and lifestyle management, we help people find tools that can improve their control of migraine disease.
- Global Burden of Disease Collaborative Network. Global Burden of Disease Study 2019 (GBD 2019) Results.; 2020.
- May A, Schulte LH. Chronic migraine: risk factors, mechanisms and treatment. Nat Rev Neurol. 2016;12(8):455-464. doi:10.1038/NRNEUROL.2016.93
- Rattanawong W, Rapoport A, Srikiatkhachorn A. Neurobiology of migraine progression. Neurobiology of Pain. 2022;12:100094. doi:10.1016/J.YNPAI.2022.100094
- Ha H, Gonzalez A, Rosa S. Migraine Headache Prophylaxis. Am Fam Physician. 2019;99(1):17-24. Accessed August 18, 2022. www.aafp.org/afpAmericanFamilyPhysician17https://familydoctor.org/condition/migraines/.
- Fischer MA, Jan A. Medication-overuse Headache. StatPearls. Published online July 4, 2022. Accessed August 18, 2022. https://www.ncbi.nlm.nih.gov/books/NBK538150/
- Velásquez-Rimachi V, Chachaima-Mar J, Cárdenas-Baltazar EC, et al. Greater occipital nerve block for chronic migraine patients: A meta-analysis. Acta Neurol Scand. Published online June 21, 2022. doi:10.1111/ANE.13634
- Moisset X, Pereira B, Ciampi De Andrade D, Fontaine D, Lantéri-Minet M, Mawet J. Neuromodulation techniques for acute and preventive migraine treatment: a systematic review and meta-analysis of randomized controlled trials. Journal of Headache and Pain. 2020;21(142). doi:10.1186/s10194-020-01204-4
- Ailani J, Burch RC, Robbins MS. The American Headache Society Consensus Statement: Update on integrating new migraine treatments into clinical practice. Headache: The Journal of Head and Face Pain. 2021;61(7):1021-1039. doi:10.1111/HEAD.14153
- Blumenfeld AM, Bloudek LM, Becker WJ, et al. Patterns of use and reasons for discontinuation of prophylactic medications for episodic migraine and chronic migraine: Results from the second international burden of migraine study (IBMS-II). Headache. 2013;53(4):644-655. doi:10.1111/head.12055
- Mascarella D, Matteo E, Favoni V, Cevoli S. The ultimate guide to the anti-CGRP monoclonal antibodies galaxy. Neurol Sci. Published online June 20, 2022. doi:10.1007/S10072-022-06199-1