The first time I experienced a migraine was one evening after school. A dull headache turned into splitting pain, blurring my vision and converting my bedroom light into a source of pure agony. Then came the vomiting. It’s a cycle I’ve experienced countless times in recent years – one that forced me to quit my job and left me feeling helpless.
A migraine attack has long been passed off as ‘just a headache’. But while ‘normal’ headaches can usually be held at bay with a paracetamol or two, a migraine is aggressive, sometimes enough to be severely debilitating. It has no conclusive cause (hormones and abnormal brain activity are just two potential reasons) or sustainable treatment on offer.
Perhaps it’s little surprise, then, that the world’s leading survey of health conditions across 195 countries found that, in every year from 1990 to 2016, migraine attacks remained the second-largest global contributor to years lived with disability. They come with a huge economic cost, too, causing an estimated 25 million sick days to be taken in the UK alone each year. But compared to their health and economic burden, migraines remain one of the world’s most under-funded diseases.
The disorder is also much more prevalent in women. In general, one in five women suffer compared to one in 15 men.
Reasons remain unclear – though a University of Arizona study of male and female rats, published in April 2018, suggests that it may be because of the link between higher oestrogen levels and lower levels of the sodium proton exchanger NHE1. Without enough NHE1, pain signalling increases. “Based on our findings, we think that women are more susceptible to migraine because the larger magnitude sex hormone fluctuations lead to changes in NHE1 expression,” researcher Emily Galloway explained.
But when it comes to research and funding, migraines have been less investigated than other ailments. Despite the enormous economic costs, they continue to receive the least public funding of any neurological illness in Europe. In the US, where migraines affect an estimated 15% of people, the condition received $22m in research funding (£17m) in 2017. Asthma, which affects half as many people, received 13 times that amount ($286m or £218m); diabetes, affecting two-thirds as many people, received 50 times as much ($1.1bn or £84m). (Of course, it’s worth noting that asthma and diabetes are potentially life-threatening conditions).
When the condition is studied, it often is affected by a trend seen in other healthcare research: most migraine research on animals has been done on males even though women suffer from migraines more, as one of the University of Arizona study researchers Emily Galloway has noted.
Given the prevalence of migraines among women, this apparent neglect could be a result of how physicians tend to underrate pain in female patients. It may also reflect the historic – and similarly gendered – associations between migraines and mental illness.