“Suicide is in many ways the oft-ignored part of gun tragedy in America, the part that few talk about, especially those who resist any efforts to decrease access to guns,” writes Frederick Rivara, a professor of pediatrics at the University of Washington, in an editorial accompanying the study. He points out that 86 percent of suicide attempts using guns end in death, compared to 2 percent of attempts using drugs.

“Rural residents often grow up with guns, have guns in their homes and there’s just a general culture of guns in rural areas,” Fontanella says. Even so, she says, suicide rates by all methods were higher in the country than in the city.

The factors that might contribute to this disparity make a snarled web of many threads. Gun access is just one of those. Rural life is isolating—and getting more so. Only 15 percent of U.S. residents live in non-metropolitan areas, which account for about 72 percent of the country, according to the U.S. Department of Agriculture. And these areas continue to lose population.

Plus, “a lot of young people are out-migrating because of the lack of employment opportunities,” Fontanella says, “which can lead to heightened degrees of social isolation for those left behind.”

For those who feel isolated, or who suffer from mental health problems that can lead to suicidal thoughts, home might not be the most comforting place. The 2006 review suggests that stigma around psychological disorders is often high in remote areas, and at least one study found that some rural regions of the U.S. (the Great Plains and Mountain West, specifically) tend to have cultures that value individual autonomy. Both of these factors could deter people from seeking help.

Even if sought, help could be hard to find. According to the Kaiser Family Foundation, there are nearly 4,000 areas in the U.S. designated as having shortages of mental-healthcare professionals, with only about 51 percent of the country’s total need met. So rural residents may have to travel long distances to get appointments, or visit primary-care physicians instead of mental-health specialists. (It's worth noting that for those who need immediate help, the National Suicide Prevention Lifeline is available 24 hours a day.)

“Folks that live in rural areas tend to go to their primary-care doctor for services because there’s less stigma,” Fontanella says, “so integrating mental healthcare in physical-healthcare settings [would be one way to address the issue], by having a mental-health practitioner on site, or through video conferencing … But it’s going to be hard to generate the numbers of mental-health practitioners to get where we need to go. So in general, we need to improve the entire system of care.”