A growing share of adolescents receiving treatment in the nation’s emergency rooms have self-inflicted injuries, according to new findings from Minneapolis pediatric researchers, but the silver lining might be that more are getting medical care before their self-harm becomes deadly.

Examining more than 280,000 adolescent visits to U.S. trauma centers, investigators with Children’s Hospitals and Clinics of Minnesota found that 1.6 percent involved self-harm in 2012, compared to only 1.1 percent in 2008.

The percentage increase might seem small, but it reflects a significant rise in adolescents whose emotional suffering results in physical harm that can have extreme and often fatal consequences, said Gretchen Cutler, lead author of the study published in Monday’s edition of Pediatrics. Even among patients receiving care at trauma centers, teens harming themselves were 12 times more likely to die than those treated for other injuries and illnesses.

The figures included adolescents who died of their injuries in emergency room care, but also those whose nonlethal forms of self-harm represented possible “gateways” to future suicide attempts, Cutler said. They also signal broader problems in the community with self-harm that never receives medical attention.

Cutler said she was motivated to pursue the study a year ago when she toured the emergency department as a new Children’s researcher and was struck by all the rooms and resources dedicated to mental health.

“There are a lot of kids who are harming themselves who do not make it to the emergency department,” Cutler said.

Few previous studies on the topic comprised such a large volume of emergency department records, which made Cutler’s findings particularly eye-catching. Some findings confirmed long-known facts, including that nonlethal self-harm is more common among young women, and that boys were more likely to use firearms while girls were more likely to cut themselves.

Others were surprising, including an overall decrease in cases that involved firearms between 2008 and 2012. Cutler said that could reflect increased physician counseling to families on securing or limiting access to firearms in their homes.

The rate of self-harm among adolescents also was higher among Asian-Americans than among whites, which was news to experts such as Dan Reidenberg, executive director of SAVE, a national suicide prevention organization based in Bloomington.

Overall, the increase in self-harm could reflect the rising pressures on today’s youth, he said.

“Kids are under extreme stress — lots of competition, fear of failure, lots of social pressures,” he said, though he noted that in almost all cases teen suicides are also linked to depression or other mental illnesses.

The increase might also reflect “increasing suicidality” in the broader American culture, said Jon Roesler, an epidemiology supervisor in the Minnesota Department of Health’s Injury and Prevention Unit.

Roesler noted that the rates of death by suicide have risen faster in the last decade for middle-aged adults and the elderly than for adolescents. “That may be the good news. Our youth may be affected less by this increased suicidality.”

Other research has linked suicidal risks in teens to adverse childhood experiences — a category that includes physical abuse, the presence of problem drinkers in a household, and divorce or separation.

Combating suicidal urges is somewhat different with teens, because their anxieties can rise and fall in minutes and can be turned on and off by something as immediate as a text message from a friend, Reidenberg said.

“Kids’ perspective are right here, right now, in this moment,” he said. “So for them ... the anxiety that gets them to a place of wanting to die can go away just as fast if there is some sort of intervention, whereas it might last longer in an adult.”

Given the juncture between self-harm and mental illness, Cutler said she was disappointed to find that only 5 percent of the ER visits resulted in a new or affirmed mental health diagnoses.

“In our minds, that is incredibly low,” she said. “It shows a missed opportunity to identify these patients, diagnose them ... and connect them with outpatient resources.”

But Reidenberg said there is a possible upside to the increase in emergency-room visits — the fact that many of the adolescents survived through the emergency care and received support to prevent suicides.

“Youth are having more problems,” he said, “but they’re being identified more readily today and they’re seeking out more help today than they have in the past.’’