Dr. Andrew Charles and his associates at UCLA just published a fascinating report on migraine aura in the journal Brain. We still do not understand the brain mechanisms that lead to the phenomenon of migraine aura. The published report characterizes a large number of visual auras recorded by a single individual over nearly two decades. This person made detailed drawings of his visual aura in real time during more than 1000 attacks of migraine aura. His auras were never followed by a headache. The drawings showed the shape and location of the aura wavefront or blackout areas in the visual field with one minute intervals. These drawings were digitized by the researchers to make it easier to analyze them. Consistent patterns of aura initiation, propagation and termination were observed in both right and left visual fields. Most aura attacks started centrally, but some also started in the periphery, which in most people is more common. The auras that started centrally moved down and in first and then up and to the side. The speed of progression of the auras was always the same. The speed was about 2-3 millimeters per minute, which is what has been reported by most other people in the past. Some auras started and then quickly stopped without progressing. In some episodes the visual aura disappeared for several minutes before reappearing in a distant location, suggesting that the aura can be clinically ‘silent’. The authors concluded that these results indicate that there can be multiple distinct sites of aura initiation in a given individual, which has never been established before. They also stated that the visual perception of migraine aura changes depending on the region of the brain’s occipital cortex that is involved. This study is another small contribution to the unraveling of the puzzle that is migraine headache.

Art credit: JulieMauskop.com

Thirty-two percent of patients with multiple sclerosis experience both migraine and pain with neuropathic (related to nerve damage) characteristics, according to a report by French researchers led by Xavier Moisse. These two symptoms appear to be caused by different mechanisms.

The authors conducted a postal survey to assess the prevalence and characteristics of neuropathic pain and migraine in multiple sclerosis (MS) patients. Of the 1300 questionnaires sent, 673 were complete enough be used for statistical analysis. Among the respondents, the overall pain prevalence in the previous month was 79%, with 51% experiencing pain with neuropathic characteristics and 46% migraine. MS patients with both migraine and neuropathic pain (32% of the respondents) reported more severe pain and had lower health-related quality of life than MS patients with either migraine or just pain. Migraine was mostly episodic, but in 15% they were chronic, meaning that they occurred on 15 or more days per month. Neuropathic pain was most often located in the extremities, back and head, and was frequently described as tingling and pins-and-needles. The intensity of pain was low to moderate. Nonetheless, patients with pain were more disabled than patients with migraine. Migraine, but not pain, was more common with older age, disease duration, relapsing-remitting course, and interferon-beta treatment.

We do see patients without a history of headaches who develop headaches, including migraines, as a side effect of interferon treatment, both when it is given for MS as well as hepatitis C. These headaches can be managed just like any other migraine or chronic migraine with magnesium, medications, Botox injections, etc., although the response to treatment sometimes is not as good. If a patient with MS has both migraines and pain, we try using medications such as gabapentin or amitriptyline, which can help both conditions.

Migraine headaches can be triggered by exposure to a variety of chemicals, including fumes, MSG, artificial sweeteners and many other. Now, scientists at the university of Kansas Medical Center published a study suggesting that BPA, a ubiquitous toxic chemical found in plastics, canned food, and ATM receipts, may be also involved in triggering migraine attacks. The New York Times columnist, Nicholas Kristof has been publicizing the dangers of BPA (bisphenol A) in many of his articles. BPA was recently banned from baby bottles and cups, but it is still widely used everywhere else and can be found in significant amounts in the bodies of 90% of the US population. It is not surprising that BPA could impact migraines because it can produce hormonal estrogen-like effects. Women are three times more likely to have migraines than men, with estrogen being the likely culprit.

The Kansas researchers hypothesized that BPA exposure exacerbates migraine symptoms through estrogen mechanisms. They studied the effect of BPA on female rats, in which a migraine-like state of increased sensitivity was induced. They studied changes in movement of these rats, light and sound sensitivity, grooming, and startle response. They also measured changes in genes related to estrogen and pain perception. After BPA exposure these rats had significantly increased migraine-like behaviors. They moved less, had an increase in light and sound sensitivity, altered grooming habits, and increased startle responses. BPA exposure also increased expression of estrogen and pain-modulating receptors. These results suggest that BPA may be also a contributing factor to migraines in humans.

This study has many limitations, with the main one being that it was done in rats. However, it is possible that BPA is one of many potential triggers which can make migraine headaches worse. However, there is little doubt that BPA is a chemical that should be avoided regardless of its effect on migraines.

White matter lesions (WML) are more common in people who suffer from migraine headaches with or without aura and my recent post mentioned yet another study confirming this finding. Researchers from Johns Hopkins School of Medicine just published a study in the journal Neurology which provides further reassurance about the benign nature of these mysterious lesions. They examined over 1,000 migraine sufferers with two MRI scans separated by 8 to 12 years. While those with migraines had a significantly greater risk of having these WML or as these researchers called them white matter hyperintensities (WMH) the number of these lesions did not increase with the passage of time. This study contradicts a larger, so called CAMERA study which showed progression of the number of WMLs in women. That study was done in younger people and the authors speculate that whatever might be causing these WML may be occurring at a younger age when the disease of migraine is most active. It is a well established fact that migraines are most common in 20s, 30s, and 40s but then tend to subside.

Art credit: JulieMauskop.com

Vertigo presenting during the peri-menopause can be related to migraine, according to a report by Nashville neurologists led by Dr. Jan Brandes. They collected information on 12 women who presented with a new onset of vertigo during their peri-menopause and who fulfilled the criteria for migrainous vertigo. Only 4 of the 12 were previously diagnosed to have migraine headaches and all of them were treated for at least a year for non-migraine causes of vertigo. Once the diagnosis of migrainous vertigo was made a combination of hormonal and conventional migraine preventive therapy produced a significant improvement in these women. The authors concluded that the appearance of vertigo during the peri-menopause should prompt an evaluation for possible migraine connection and if such connection is found the treatment should include a combination of hormonal and traditional migraine therapies.
Other non-migraine causes of vertigo include inner ear problems, brain disorders, such as strokes and tumors, and neck muscle spasm. The latter usually causes dizziness rather than true vertigo, which is defined as a spinning sensation. Dizziness can also be caused by drop in blood pressure, especially on standing up, peripheral nerve damage (such as in diabetes or vitamin B12 deficiency), eye, and other conditions.

Art credit: JulieMauskop.com