A study in Maryland shows rural areas have a 35 percent higher suicide rate than urban regions. Researchers say firearms are the primary reason.

Suicide rates in rural areas of Maryland are 35 percent higher than in cities.

The reason, concludes a new study, is firearms.

Research published today in the American Journal of Public Health further cements the link between gun violence and suicide.

While suicide rates in rural areas are statistically higher than urban counterparts, the high rate difference only holds true for suicides where a gun is used.

“This link may be strong enough to explain the much-debated roots of the relatively higher suicide rates in rural areas, overshadowing other important factors such as access to mental healthcare,” Dr. Paul Nestadt, a psychiatrist in Baltimore and the study’s lead researcher, told Healthline.

Other experts have theorized that higher suicide rates in rural areas are connected to a greater prevalence of depression and mental health disorders.

Nestadt and his colleagues argue against the notion, putting the blame squarely on guns.

In the study, Nestadt and his co-researchers analyzed 6,200 suicides in the state of Maryland between 2003 and 2015.

In urban areas, the suicide rate was 16 deaths per 100,000. The rate in rural counties was more than 24 deaths per 100,000.

However, when firearm suicides were taken out of the equation, suicide rates in urban and rural areas were more comparable.

Suicide is currently the 10th-leading cause of death in the United States.

Rates have risen from 10 deaths per 100,000 people in 2014 to 13 deaths per 100,000 in 2015. The rate of suicide in the United States is now at the highest it’s been in 30 years.

Roughly half of all suicides utilize firearms, according to the Centers for Disease Control and Prevention (CDC).

In fact, far more people die every year from firearm suicide than homicide in the United States.

Nestadt’s research comes as the latest in a wave of increasing scrutiny on the relationship between guns and suicide.

A study in 2015 found that youth suicide rates in rural areas were significantly higher, but it was less explicit than Nestadt as to why this was the case.

In an editorial for the Harvard School of Public Health, author Madeline Drexler notes that in states with the highest rates of gun ownership, firearm suicide rates are 3.7 times higher for men and 7.9 times higher for women when compared with those with the lowest rates of gun ownership.

The scope of Nestadt’s research is limited by its use of data from a single state, but he explains that it’s still pertinent to a national discussion.

“The findings in Maryland [are] applicable to [a] majority of populous states and means that our findings regarding rural areas are relevant to the most common type of rural area in the U.S.,” he said.

In light of their findings, researchers have called for further study into firearm regulation and safety practices as a means of preventing suicide.

Those regulations include instructing gun shop owners to monitor buyers who exhibit certain red flags, such as only buying a few bullets or showing little interest in how to maintain a gun.