Weathering a Migraine

How climate and temperature changes can trigger headaches

By Amy Norton
Special to MSN

A recent stretch of unusually mild January days in the Northeast seemed a welcome dose of spring for the many people who emerged from their winter hibernation daringly clad in T-shirts.

But Nicole Field, a 23-year-old college student from Pennsylvania, found herself dreading the 60-plus-degree weather being forecast for the next day. Sharp changes in temperature trigger her migraine headaches, she says, and that atypical rise to the 60s was set to be followed by a sudden drop to typical January temperatures.

Since last summer, Field says, she's noticed that "any big jump" in temperature from day to day can set off throbbing head pain, pressure in her face and even pain in her teeth. When a weather report warns of a sharp shift on the thermometer, she keeps her medication handy.

That's a good idea, according to Dr. Alan M. Rapoport, co-founder and director of The New England Center for Headache in Stamford, Conn., and a clinical professor of neurology at Columbia University in New York.

Specifically, he says, people who know that certain weather conditions trigger their migraine attacks should keep their triptan medications at the ready, taking the drug at the first sign of symptoms.

These symptoms include throbbing pain, often concentrated on one side of the head, and, in many cases, nausea and sensitivity to light and sound.

A dreary forecast
Researchers are still foggy on why weather conditions — such as extremes in temperature, high or low humidity levels, or changes in atmospheric pressure — set off migraine attacks in some people, according to Rapoport. What is clear, he says, is that weather is a trigger for many migraineurs.

In a recent study, Rapoport and his colleagues found that roughly half of the 77 migraine patients they followed could count weather conditions as a trigger. High and low temperatures and humidity levels were the top factors; sudden major shifts in weather conditions, such as a passing weather front, and extremes in barometric pressure were also common triggers.

The researchers arrived at their conclusions by having the patients keep daily headache "calendars" in which they recorded their migraine attacks, and then comparing those notes with data from nearby weather monitoring stations.

Similarly, migraine sufferers who think weather is a trigger for them can try to pinpoint the culprit by keeping a record of when they get attacks, and — with the help of the Weather Channel or the Internet — the specific weather conditions at the time.

Dr. Seymour Diamond, director of the Diamond Headache Clinic in Chicago, says all patients at his clinic keep headache diaries in order to zero in on triggers, weather or otherwise.

People with migraine vary widely in what triggers their head pain — from menstrual-related hormone fluctuations to red wine to getting too much or too little sleep. And though some studies have doubted that weather acts as a trigger, Diamond says, clinical experience tells him otherwise.

"We see such an influx of patients with it," he says.

Something in the air
Besides temperature, humidity and barometric pressure, other weather-related culprits include the bright light of a sunny day — which, Diamond notes, a pair of tinted glasses can counter — as well as hot, dry winds. Studies have found that certain winds — such as the so-called Santa Ana winds of California and the Chinook winds that blow across the northwestern U.S. and western Canada — seem to serve as migraine triggers.

One theory on wind-related migraine that Diamond points to has to do with the charged ion particles in the air, which are affected by winds.

"Changes in ionization in the air may affect the amount of serotonin in the body," Diamond says. Fluctuations in serotonin, a brain chemical that helps regulate blood-vessel contraction and dilation, are thought to be key in the migraine process.

Barometric pressure, which reflects the weight of the air, can trigger a migraine when the barometer drops on an overcast day — which may explain why some migraineurs say they can predict the rain — or when it rises on a clear day. Some scientists have speculated that the effects of atmospheric pressure on blood vessels could explain this link.

However, Rapoport says the mechanisms by which various weather conditions may trigger migraine are not yet understood. The brain, he notes, "can tell" when it's hot or cold, but the details of how a weather change translates into a migraine attack for some people are unclear. Whatever the reasons, knowing which weather conditions spell trouble for you is a valuable weapon. And if preparedness for an attack isn't enough, Rapoport points out, there is always the option of moving to a place where the weather outlook is a bit more cheerful for you.

__________________________________________________________________________________