Native Americans suffer from higher rates of trauma than the general U.S. population, according to a comprehensive study of more than 3,000 tribal members.

Statistics have shown that American Indians and Alaska Natives are more likely to be victims of violence, including sexual assaults, than other racial and ethnic groups. But in the May issue of the American Journal of Public Health, researchers say they have provided the first "systematic" assessment of the health and well-being of members of two tribes -- one in the Southwest and another in the Northern Plains.

"Unlike the US general population, female and male American Indians exhibited equivalent levels of overall trauma exposure," the authors from the University of Colorado wrote. "Members of both tribes more often witnessed traumatic events, experienced traumas to loved ones, and were victims of physical attacks than their counterparts in the overall US population. than among other groups."

The conclusion is based on a long-term survey of 3,084 tribal members who live within 20 miles of their reservations. The identities of the tribes involved were not disclosed to protect their privacy.

Despite differences in history and culture, members of the two tribes reported equally high rates of trauma. According to the study, lifetime exposure to trauma among male tribal members ranged from 62.4 percent to 67.2 percent and from 66.2 percent to 69.8 percent among female tribal members.

These rates were higher than the national averages of 60.7 percent for men and 51.2 percent for women, the researchers noted. They suggested that one cause for the disparity could be alcohol abuse among tribal members but that they haven't drawn a concrete conclusion.

In addition to the high rates of trauma, the researchers reported an "unexpected" discovery with respect to education, employment and poverty. Studies of the general population have linked violence to poverty, unemployment and a lower levels of education.

But the researchers said the opposite was the case among tribal members. For example, female tribal members who attended college were more likely to report being victimized than those who didn't.

The authors said they "anticipated that, in this study, impoverishment and lower levels of education and employment would be linked to greater trauma exposure. That they were not is puzzling and deserves further consideration."

Among female tribal members, the study confirmed high rates of rapes and domestic violence. According to the data, 12.8 percent of female members of the Southwest tribe and 14.4 percent of female members of the Northern Plains tribe had been raped in their lifetimes.

Additionally, 28.9 percent of Southwest female tribal members and 31.0 percent of Northern Plains tribal members had been physically abused or hurt by their intimate partner.

Other traumas were common among male and female tribal members. Nearly half of Southwest tribal members and slightly over half of Northern Plains tribal members said they witnessed violence, rapes, injuries murders, accidents and disasters.

"American Indians live in adverse environments that place them at high risk for exposure to trauma and harmful health" conditions, wrote Dr. Spero Manson, the lead author.

Other studies have drawn similar conclusions. Native Americans who attended boarding schools or who were abused as children were more likely to have problems with alcohol later in life, according to a September 2003 study in the American Journal of Preventive Medicine.

In November 2003, the Centers for Disease Control and Prevention found that Bureau of Indian Affairs students who engaged in high-risk behaviors like tobacco, alcohol and drug use are at "at risk for premature death and disability" in their lifetimes.

Get the Study:
Social Epidemiology of Trauma Among 2 American Indian Reservation Populations American Journal of Public Health May 2005) Note: Full study requires subscription or paid access.