Suicide rates in America are rising for the first time since the early ‘90s, and the most affected demographic group seems to be white, middle-aged women, according to a new study published in the American Journal of Preventive Medicine.

The analysis, conducted over a six-year period, shows that the U.S. suicide rate has risen to 11 per 100,000 people in 2005, up from 10.5 per 100,000 in 1999. The study’s findings indicate that most of this increase was constituted by a 16% spike in suicide rates among people ages 40 to 64, especially women. This group is usually seen as offering the least cause for concern.

“Adolescent, young adult and elderly populations are on our radar, because completed suicides have traditionally been higher in elderly white men and because of high suicide attempt rates and potential years of life lost in young people,” said Holly Wilcox, assistant professor with the department of psychiatry and behavioral sciences at Johns Hopkins School of Medicine, who co-authored the study. “We have some school-based and primary care prevention efforts in place to carefully monitor both ends of the age spectrum. I don’t usually worry about the middle-aged group. It’s alarming to me,” she said in the December issue of the journal, in which the study was published. The study also shows that while guns remain the favourite method for committing suicide, their use has declined over the years. Poisoning/pills as well as hanging have gained in popularity.

Sociological studies generally show that the middle age is a period emotional security and well-being, and the author of the study, Susan P. Baker, an epidemiologist at Johns Hopkins University Bloomberg School of Public Health, says she and her colleagues are dumbfounded by the results.

"We really don't know what is causing this," said Dr. Paula Clayton, research director of the American Foundation for Suicide Prevention. "All we have is speculation."

Several proposed theories link the increase in suicide to the abuse of prescription pain pills, as past studies have put people who abuse drugs at a greater risk of suicide; another, albeit linked explanation is the drop in hormone replacement therapy, after it was tied to health risks in 2002. Women who’ve stopped taking the drugs have become more susceptible to depression and possibly suicide.

Other medics and researchers accuse the stresses of modern life, and worries about the aftermath of the terrorist attacks of Sept. 11, 2001. The recent economic crisis in the United States, if this theory is to be considered true, may also cause a sharp increase in suicide rates as well, although men would more likely be more affected by this particular cause, because they tend to be more active in the economic field and hold jobs with greater economic responsibility, and responsibility to their families. Confer the Japanese economic crisis following the collapse of Japan’s bubble economy, which saw an exponential increase in suicide rates among Japanese businessmen.