A number of studies have found that people with migraines tend to have a higher suicide rate than those without it. — File Photo

People with severe headaches, whether migraines or not, may be more likely to attempt suicide, according to a US study of more than a thousand people.

A number of studies over the years have found that people with migraines tend to have a higher suicide rate than those without, but it has not been clear if this is related specifically to the “biology of migraines,” said Naomi Breslau of Michigan State University at East Lansing, who led the study.

“We haven't known if it was the migraines or the pain more generally,” Breslau told Reuters Health, though her findings, published in the journal Headache, don't prove that headaches caused the suicide attempts.

The study followed nearly 1,200 Detroit, Michigan-area adults. About 500 of them were migraine sufferers, while 151 had severe headaches that were not migraines.

The rest were free of serious headaches and served as a comparison group.

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

Over two years, the migraine and severe-headache groups had similar rates of attempted suicide. Almost nine per cent of migraine sufferers said they'd tried to kill themselves, as did 10 per cent of those with severe non-migraine headaches.

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

“We're ruling out that it's only migraine” that's related to suicide risk, Breslau said, adding that common tension-type headaches usually don't come close to the pain severity of migraines – but can in some cases.

The difference is that migraines have distinct features, such as nausea and vomiting, sensitivity to light or sound, and throbbing pain on one side of the head only.

So why are severe headaches related to suicide risk? Depression plays a role, Breslau said, but 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.

Researchers said there may be some biological underpinnings.

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 specialised pain clinic.