Nearby lightning may be linked to migraines
By Andrew M. Seaman
NEW YORK | Fri Jan 25, 2013 5:06pm EST
(Reuters Health) - Weather has long been considered one of many potential migraine triggers, but a new study links lightning, specifically, to the onset of the severe headaches that plague more than 28 million Americans.
Based on headache logs and weather data for Ohio and Missouri, researchers found that people were 28 percent more likely to experience a migraine on days when lightning struck within 25 miles of their home.
"We're very surprised and very happy with the results in that this is the first study to link lightning to migraines," said Dr. Vincent Martin, the study's senior author from the University of Cincinnati College of Medicine in Ohio.
Migraines are severe headaches - sometimes accompanied by light sensitivity, visual hallucinations or nausea - that can disable a person for hours or even days at a time. The majority of migraine sufferers are women.
Martin told Reuters Health that a migraine may result from a person experiencing certain "triggers," such as stress, lack of sleep and dehydration.
Previous research has also found links between the onset of migraines and high barometric pressure, high temperatures and high humidity.
Most of the past studies looking at weather and migraines, however, relied on an individual's observations and did not always account for other, possibly unseen, local weather conditions, the researchers write in the journal Cephalalgia.
For the new study, they used information collected from three sensors that track lightning near Cincinnati, Ohio, and five sensors near St. Louis, Missouri. Those sensors allowed the researchers to know where and when lightning struck and the intensity of each strike.
They also used the headache diaries from two previous studies of 90 migraine sufferers in those areas who were between 18 and 65 years old. In those diaries, the participants recorded their headaches for three to six months.
After comparing the weather data with the headache journals, the researchers found that a lightning strike within 25 miles of a person's house was linked to a 31 percent increased risk of any kind of headache, and a 28 percent increased risk of the more severe migraine headache.
Martin said that could mean an extra one to three migraines per month for an individual, but he added that it depends on the person and the weather.
As for how lightning might affect migraine occurrences, Martin said it could be that the electromagnetic waves and ozone created by the lightning have something to do with it.
"The other theory is that when these thunderstorms roll in they can create more allergy spores in the environment," he said, which could create a problem for some people.
But the researchers cannot say for certain that lightning causes migraines, even though they used a computer model to account for other meteorological changes that occur during a thunderstorm.
In an accompanying editorial, Dr. Hayrunnisa Bolay of Gazi University in Ankara, Turkey, cautioned that the study had limitations, including its failure to account for the participants' own individual risk factors.
"In brief, one can only conclude that weather conditions associated with lightning have the potential to induce headache in migraine patients," she wrote.
SOURCE: bit.ly/UpWoFJ and bit.ly/11XhL5w Cephalalgia, online January 24, 2013.
Lightning and its association with the frequency of headache in migraineurs: An observational cohort study
Published online before print January 24, 2013, doi: 10.1177/0333102412474502
Cephalalgia January 24, 2013 0333102412474502
Geoffrey V Martin1,
Albert Peterlin4 and
Vincent T Martin1
+ Author Affiliations
1Department of Internal Medicine, University of Cincinnati College of Medicine, OH, USA
2Department of Anesthesiology, Wake Forest Medical Center, NC, USA
3Department of Neurology and Psychiatry, St. Louis University and Mercy Health Research and Ryan Headache Clinic, MO, USA
4Environmental Rights and Releases Exchange (ERREx) Inc, PA, USA
Vincent T Martin, University of Cincinnati, Department of Internal Medicine, University of Cincinnati, 231 A. Sabin Way, Room 6304, Cincinnati, OH 45267-0535, USA. Email: email@example.com
Aim The aim of this article is to determine if lightning is associated with the frequency of headache in migraineurs.
Methods Participants fulfilling diagnostic criteria for International Headache Society-defined migraine were recruited from sites located in Ohio (n?=?23) and Missouri (n?=?67). They recorded headache activity in a daily diary for three to six months. A generalized estimating equations (GEE) logistic regression determined the odds ratio (OR) of headache on lightning days compared to non-lightning days. Other weather factors associated with thunderstorms were also added as covariates to the GEE model to see how they would attenuate the effect of lightning on headache.
Results The mean age of the study population was 44 and 91% were female. The OR for headache was 1.31 (95% confidence limits (CL); 1.07, 1.66) during lighting days as compared to non-lightning days. The addition of thunderstorm-associated weather variables as covariates were only able to reduce the OR for headache on lightning days to 1.18 (95% CL; 1.02, 1.37). The probability of having a headache on lightning days was also further increased when the average current of lightning strikes for the day was more negative.
Conclusion This study suggests that lightning represents a trigger for headache in migraineurs that cannot be completely explained by other meteorological factors. It is unknown if lightning directly triggers headaches through electromagnetic waves or indirectly through production of bioaerosols (e.g. ozone), induction of fungal spores or other mechanisms. These results should be interpreted cautiously until replicated in a second dataset.
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