On menstrual migraines, pregnancy and strokes
Several months ago, a young would-be mother, who was in her first trimester of pregnancy, was referred to our clinic for a pounding headache, which was attributed to a high-normal, at most marginally elevated blood pressure. Even before her pregnancy, she would have migraine attacks, especially when she’s under stress.
The character of the headache was classical migraine—throbbing pain felt on one side of the head, preceded minutes earlier by visual symptoms like seeing “weird white spots or wavy lines floating in the air,” as the patient described it. This is the typical aura of migraine headache, usually felt half to one hour prior to the onset of the headache.
We assessed the patient’s problem to be primarily due to her migraine, which caused her blood pressure to increase, rather than the other way around, that is, elevation of the BP causing the severe headache. It’s important to distinguish this, particularly in a pregnant woman because the treatment is totally different.
Women, generally, are more predisposed to migraine than men because of the influence of hormonal changes throughout the woman’s lifecycle. According to the literatures, 70 percent of migraine sufferers are females. Some would have “menstrual migraine,” so-called because it occurs during and around the menstrual period, and this occurs in about one-third of the time in female sufferers.
Migraines are related to fluctuations in the levels of the female hormone estrogen during a woman’s menstrual cycle, such that when estrogen levels drop immediately before the start of the menstrual flow, migraines may be experienced. During pregnancy, the sustained high levels of the female hormones is supposed to protect women from migraine attacks. However, the levels may not be high enough in the first trimester so they can still have migraine episodes such as in the patient we saw.
Migraine-free for now
The migraines usually wane or disappear during the second and third trimesters of pregnancy. Our patient is now in her last trimester, and she says she has been migraine-free for now. We warned her, though, that after delivery (post-partum), her migraines might recur because of the abrupt fall-off of her estrogen levels.
Pregnant migraine sufferers have to consult their physicians for their anti-migraine remedies during pregnancy because most of the pills they could take when not pregnant are contraindicated during pregnancy. Nondrug therapies (relaxation meditation, sleep, massage, ice packs, biofeedback) should be tried first, and only if this does not work can some medicines be prescribed.
Preventive or prophylactic treatment is not recommended and the only agents that can be given during pregnancy are the beta-blockers metoprolol and propranolol but again, their possible side effects on the baby in the womb have to be weighed versus the benefit on the mother. They’re usually given only in frequently recurring migraines.
There are now new research data, giving us a better understanding of the long-term impact on health of migraine headaches. It is now regarded as something that could be part of a much more complicated problem. Before, we used to think that migraine is a bothersome but otherwise benign or non-serious type of headache. Published data over the last five years suggest that it may not really be as harmless as it was believed to be.
Headache experts are now exploring the link between migraine and stroke, and they’re saying that people who suffer from migraine headaches have an increased risk of stroke compared to those without migraine. In fact, there are cases reported of an actual stroke diagnosed during a typical migraine attack, especially during or after a “thunderclap headache,” which is a much more severe attack of migraine.
Most migraine sufferers
Because migraine occurs more frequently in women, most migraine sufferers who develop stroke are women too. They’re usually younger—less than 50 years of age, and may not have the traditional risk factors for stroke, like diabetes, hypertension or cholesterol problems. However, smoking and intake of birth control pills have been identified as risk factors in these women.
The implicated mechanism is tightening of the brain arteries due to spasm, which can be severe enough to stop blood flow to some areas of the brain. When this is sustained for a relatively long period, this can lead to stroke.
For migraine sufferers in general, the coexistence of migraine and high blood pressure is also bad news. Earlier this year, during the International Society of Hypertension congress, Dr Enrico Agabiti-Rosei from the University of Brescia in Italy, presented the findings of their published study, which showed that patients with both hypertension and migraine headaches had a higher probability of a history of stroke than patients with high BP but no migraine.
“The prevalence of hypertension and migraine comorbidity is clinically rare, but doctors should pay attention when they see this, because it might help identify patients at risk of an event. Migraine might be considered as a factor to be included in the score for risk of stroke,” Dr. Rosei said.
Identifying this migraine sufferers “at risk” for stroke can sometimes be a dilemma. As in the case we cited, the physician has to make sure that the patient is really hypertensive with episodes of migraine, and not someone who has normal blood pressure and whose BP only increases during migraine attacks. Well, the practice of medicine can sometimes be tricky.