The findings don't prove that headaches caused the suicide attempts, but a number of studies over the years have found that people with migraines tend to have a higher suicide rate than those without the problem.

But it has not been clear whether it's related specifically to the "biology of migraines," said Naomi Breslau of Michigan State University in East Lansing, who led the new study.

"We haven't known if it was the migraines or the pain more generally," Breslau told Reuters Health.

Based on these latest findings, it may be the severity of the pain that matters, migraine or not, the researchers say.

The study, reported in the journal Headache, followed nearly 1,200 Detroit-area adults. About 500 of them were migraine sufferers, while 151 had severe headaches that were not migraines. The rest Over two years, the migraine and severe-headache groups had similar rates of attempted suicide. Almost nine percent of migraine sufferers said they'd tried to kill themselves, as did 10 percent of those with severe non-migraine headaches.

That compared with a rate of just over one percent in the comparison group.

"We're ruling out that it's only migraine" that's related to suicide risk, Breslau said. Usually, she added, common tension-type headaches "don't come close" to the pain severity of migraines. But they can in some cases.

The difference is that migraines have some distinctive features -- like nausea and vomiting, sensitivity to light or sound, and throbbing pain on one side of the head only.

In this study, severe non-migraines were defined as an intense headache lasting more than four hours.

So why are severe headaches related to suicide risk? Depression plays some role, Breslau said, but it doesn't tell the whole story.

When Breslau's team factored in people's history of depression, anxiety and past suicide attempts, they found that migraine and headache sufferers were still four to six times more likely to attempt suicide than the comparison group.

There may be some biological underpinnings at work, according to the researchers. Certain brain chemicals, including serotonin, are thought to be involved in severe headaches, and dysfunction in those chemicals has also been linked to suicide risk.

The bottom line, according to Breslau, is that people with severe head pain should seek help from their doctor -- or, if needed, a specialized pain clinic.

The treatment for migraine or severe headaches is often similar. If standard painkillers are not enough, doctors may recommend other medications -- like antidepressants or triptans, which raise serotonin levels.

Certain other drugs, like some high blood pressure or anti-seizure medications, are sometimes given to prevent migraine attacks.

A non-drug option is biofeedback, where people learn to control the physical responses to stress, like muscle tension -- which may help head off or ease migraine pain.

One of the researchers involved in the study reported having ties to manufacturers of migraine treatments. SOURCE: Headache, online March 9, 2012

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