Homeless young people living in San Francisco are 10 times more likely to die before their time, according to a new study.

Researchers at the University of California, Berkeley, found that suicide and substance abuse played a substantial role in higher mortality rates among San Francisco's homeless youth.

"This population is highly stigmatized. That stigma leads to neglect and, in turn, to increased mortality. All the deaths in this cohort were preventable," said Colette Auerswald, a pediatrician and adolescent medicine specialist who is an associate professor of public health at UC Berkeley, who led the study. "Stigma kills."

The latest study was conducted between 2004 and 2010 and was part of a larger longitudinal study of how social environments play a role in determining the health of homeless youth in San Francisco. The study involved 218 young people aged 15 to 24 years of age. People were considered to be homeless if they reported inconsistent housing for at least two days during the previous six months.

Results from the six-year long study revealed that 5 percent of the participants died. Researchers noted that the mortality rate for homeless youth in San Francisco was 10.6 times higher than their peers who lived in permanent homes. Further analysis revealed that three of the deaths were suicides, one was a homicide and seven were related to drug or alcohol use.

"This is the first North American study of mortality, and the only one I know of globally, focused solely on a street-based cohort of youth," Auerswald said.

"These sobering data provide evidence of what homeless youth face when their only option is life on the streets," added Sherilyn Adams, executive director of Larkin Street Youth Services in San Francisco. "We must not ignore or underestimate the gravity of homelessness or its tragic impact on young lives cut short. No young person deserves to die a preventable death because they didn't get the help they needed."

"It is critical that we have on-demand access to substance abuse treatment for all youth, including minors, in San Francisco, where drugs are a huge problem regardless of homelessness," Auerswald said. "Drugs are a major cause of morbidity and mortality and of the failure of young people to remove themselves from the street."

The findings were published in the journal PeerJ.