In what is a rather sad study, researchers revealed that in about the last 15 years, suicide rates among US adults have risen by 40 percent.

This astonishing number, pertaining to those between 40 and 64 years old in the United States, could possibly be due to the economic downturn of 2007-2009, researchers say. The recession negatively affected house values, household finances, and retirement savings for that age group, which may explain why there was a sharp rise in suicide rates in 2007.

"Relative to other age groups, a larger and increasing proportion of middle-aged suicides have circumstances associated with job, financial, or legal distress and are completed using suffocation," the researchers said in a press release. "The sharpest increase in external circumstances appears to be temporally related to the worst years of the Great Recession, consistent with other work showing a link between deteriorating economic conditions and suicide."

The team based their findings on data of 17 distinct suicide circumstances from the National Violent Death Reporting System (NVDRS). They took into account planning and intent factors in the two weeks prior to the suicide, including leaving a note or a history of prior attempts.

They found that external economic factors - for example, a job or financial problem, legal problem, or difficulty in school - were present in 37.5 percent of all completed suicides in 2010, a jump from 32.9 percent in 2005.

Interestingly, from 2005-2010, 59.5 percent more victims aged 40-65 used the method of suffocation, compared with 18 percent for those aged 15-39 years and 27.2 percent for aged over 65 years of age.

To prevent further suicide victims, the researchers recommend that human resource departments, employee assistance programs, state and local employment agencies, credit counselors, and others who interact with those in financial distress should learn how to better recognize people at risk and make referrals. In addition, increasing access to crisis counseling and other mental health services could be beneficial.

The results were published in the American Journal of Preventive Medicine.

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