The suicide rate in the U.S. is on the rise, according to a report from Johns Hopkins University.

Researchers found that the overall rate rose 0.7 percent from 1999 to 2005. But the rate for white women ages 40 to 64 rose 3.9 percent. The increase for men in that age group was 2.7 percent.

The rate for black people decreased significantly and remained stable among Asian and Native Americans. A news release on the study did not report the total cases of suicide over that time period or what the previous rates had been.

The news release said that, overall, guns remain the most common way to commit suicide, but the rate of firearm suicides fell. Hanging and suffocation made up 22 percent of the cases, followed by poisoning at 18 percent.

Although it would not appear in a long-term study such as this one, some authorities have worried that the recent financial troubles could result in more violence and suicides.

Study co-author Susan Baker said the results may mean changes in efforts to stop people from killing themselves.

"Historically, suicide prevention programs have focused on groups considered to be at highest risk -- teens and young adults of both genders as well as elderly white men. This research tells us we need to refocus our resources to develop prevention programs for men and women in their middle years," she said.

She also was not sure why the rate is increasing for middle-aged people.

"While it would be straightforward to attribute the results to a rise in so-called mid-life crises, recent studies find that middle age is mostly a time of relative security and emotional wellbeing," said Baker.

The results were published online at the website of the American Journal of Preventive Medicine and will be published in the December print edition of the journal.