The rise in U.S. suicides from 2000 to 2010 is largely attributable to an increase in hangings and suffocations – particularly among men and women ages 45 to 59, research published Tuesday morning finds.

Reporting in the December issue of the American Journal of Preventive Medicine, researchers from the Johns Hopkins Center for Injury Research and Policy have pinned down the trends behind suicide’s sobering rise in recent years. Noting that suicide has surpassed motor vehicle crashes as the leading cause of injury death in the United States, the authors used data from the CDC’s Web-Based Injury Statistics Query and Reporting System (WISQARS) to get a better handle on who tried to kill themselves, and how.

During the period studied, suicide rates among people ages 45 to 59 increased by 39 percent; among people age 70 and up, they decreased by 8 percent.

Other key findings:

● Suicide by firearm continues to account for the majority of suicides, but such suicides declined from 56 percent of all suicides in 2000 to 50 percent in 2010. Those suicides plus those by hanging/suffocation and poisoning accounted for 93 percent of all U.S. suicides.

● Suicide by firearm decreased by 24 percent among people ages 15 to 24 but increased by 22 percent among those ages 45 to 59.

● Overall, suicide by hanging/suffocation increased from 19 percent of all suicides in 2000 to 26 percent of all suicides in 2010. But suicide by hanging/suffocation increased by 104 percent among people ages 45 to 59 – the largest increase for any age group.

●The proportion of suicides attributed to poisoning rose slightly, from 16 percent in 200 to 17 percent in 2010 – but among people ages 60 to 69, suicide by poisoning increased by 85 percent.

● The rates of suicide increased more quickly among females than among males (increasing by 26 percent and 11 percent, respectively) and among whites (by 20 percent) than among Asians (12 percent) or Native Americans (10 percent); the suicide rate among blacks decreased by 6 percent from 2000 to 2010.

The authors explain that determining what methods of suicide people choose is key to developing interventions and prevention strategies. “The dramatic increase in suicide by hanging in the U.S. is of special concern because of the widespread availability of rope and other accessories used in hanging,” the study observes.