Headache specialists are still unraveling the mysteries of migraines and other headaches. Most believe a combination of factors, from genetics to neurovascular imbalances in the brain, play a role.
But what role could weather play? One leading evolutionary theory is that getting a headache is a protective mechanism against adverse environmental stressors. The theory goes that headache pain would cause someone to seek a safer, more hospitable environment. The fact that changes in weather and extremes in heat and cold cause headache, some experts believe, gives credence to this theory.
When someone has a basilar migraine, there is a disturbance in the brainstem or lower part of the brain. Even before the migraine headache begins, the person may experience an ''aura,'' consisting of a variety of symptoms such as dizziness, double vision, and lack of coordination. An aura is a neurological phenomenon that occurs about 10 minutes to 45 minutes before the headache starts.
Basilar migraines are known by several different names:
In a survey by the National Headache Foundation, headache sufferers were given a list of 16 possible triggers. They then were asked to rank them in terms of what commonly brought on their migraines and other headaches. Three out of every four respondents said that weather triggered their headache pain. Specific weather triggers include:
Changes in humidity
Changes in temperature
Extremely dry conditions
Listed below are common environmental triggers for headaches included in the survey and the percentage of people who identified them as triggers. People often have more than one type of trigger for their headaches. How many, if any, of these factors trigger your headaches?
Weather or barometric pressure changes: 73%
Intense odors: 64%
Bright or flickering lights: 59%
Extreme heat or cold: 38%
Altitude changes: 31%
High winds: 18%
Most of the participants reported that these environmental triggers have kept them from participating in their normal outdoor activities. They also said they'd stayed away from places likely to have smoke in the air, such as restaurants or bars.
Why Weather Triggers Headaches and Migraines
As noted earlier, there is a theory that headaches triggered by extreme weather are a protective, or defensive, response because they lead the person to seek a more hospitable environment.
Experts believe that people who get frequent headaches have a greater sensitivity to changes in the environment. They also have a lower threshold to the pain response. The reason, they suspect, is that people who get migraines have likely inherited this sensitivity.
The survey cited earlier also found that two out of three headache sufferers had not discussed environmental triggers with their doctors. Nearly half of them, though, had been plagued by headaches for more than 20 years.