Owning a handgun is associated with a dramatically elevated risk of suicide, according to new Stanford research that followed 26 million California residents over a 12-year period.

The higher suicide risk was driven by higher rates of suicide by firearm, the study found.

Men who owned handguns were eight times more likely than men who didn’t to die of self-inflicted gunshot wounds. Women who owned handguns were more than 35 times more likely than women who didn't to kill themselves with a gun.

While prior studies have found higher rates of suicide among people who live in homes with a gun, these studies have been relatively small in scale and the risk estimates have varied. The Stanford study is the largest to date, and it’s the first to track risks from the day of an owner’s first handgun acquisition.

“Our findings confirm what virtually every study that has investigated this question over the last 30 years has concluded: Ready access to a gun is a major risk factor for suicide,” said the study’s lead author, David Studdert, LLB, ScD, MPH, professor of medicine at Stanford Health Policy and of law at Stanford Law School.

The study, which was published June 4 in The New England Journal of Medicine, analyzed data on handgun acquisitions and deaths in a cohort of 26.3 million adult residents of California who had not previously owned handguns. The researchers followed the cohort from 2004 through 2016, and compared death rates among those who did and didn’t acquire handguns, with a particular focus on suicides by firearm versus other methods.

More than 1.4 million cohort members died during the study period. Nearly 18,000 of them died by suicide, of which 6,691 were suicides by firearms.

‘Often impulsive acts’

“Suicide attempts are often impulsive acts, driven by transient life crises,” the authors write. “Most attempts are not fatal, and most people who attempt suicide do not go on to die in a future suicide. Whether a suicide attempt is fatal depends heavily on the lethality of the method used — and firearms are extremely lethal. These facts focus attention on firearm access as a risk factor for suicide especially in the United States, which has a higher prevalence of civilian-owned firearms than any other country and one of the highest rates of suicide by firearm.”