Americans have gotten more stressed-out in the past 25 years, according to a new study.

Using surveys from 1983, 2006 and 2009, the research from Carnegie Mellon University's Sheldon Cohen and Denise Janicki-Deverts found a 10 to 30 percent increase in stress levels among all demographic categories over the past quarter-century.

The study revealed women have it worst.

"In all three surveys, women reported more stress than men," Cohen told BusinessNewsDaily. "That is pretty consistent with past findings."

Cohen said there are several possible explanations, including that females are more sensitive to certain life events.

"Women actually experience more, or different, life events than men," Cohen said, also proposing the possibility that females also are more sympathetic than men to those in their social circle. "Things that happen to friends and family affect them more."

Interpreting the same events differently and coping differently are other possible reasons for the disparity in stress levels between the two sexes, according to Cohen.

Men weren't without stress, however. The research revealed white, middle-aged men with college educations and full-time jobs saw the highest increase in stress between 2006 and 2009, which was the height of the economy's Great Recession.

"That group had a substantial increase in stress," Sheldon said. "It was two times more than any other demographic."

Sheldon chalked up those results to the belief that that group may have had the most to lose in the bad economy, since both their jobs and savings were at risk.

While numerous recent studies have reported on employees' fears of having enough money and enough to do during retirement, the study found that current retirees had very low stress levels.

"We interpret the world differently as we get older," Cohen said. "You have fewer negative emotions."

The study, one of the first to compare stress levels across the United States over a substantial period of time, used telephone survey data from 1983 that polled 2,387 U.S. residents over age 18 and online surveys from 2006 and 2009 that each polled 2,000 American adults. All three surveys used the Perceived Stress Scale, a measure created by Cohen to assess the degree to which situations in life are perceived as stressful.

The researchers conducted the study to determine whether psychological stress is associated with gender, age, education, income, employment status and/or race and ethnicity, since differences in stress between demographics may be important markers of populations under increased risk for physical and psychological disorders.

Other demographics that saw increased stress levels between 1983 and 2009 were lower-income individuals and those with less education.

The study was published in the June issue of the Journal of Applied Social Psychology.

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Stress and the recession: Who was hardest hit?
Americans have gotten more stressed-out in the past 25 years, according to a new study.