LOS ANGELES, CA (Catholic Online) - According to researchers at the Carnegie Mellon University in Pittsburgh, stress increased 18 percent for women and 24 percent for men from 1983 to 2009. Scientists studied data from more than 6,300 people. The study is considered the first-ever historical comparison of stress levels across the U.S.

"The data suggest there's been an increase in stress over that time," psychologist and lead author Sheldon Cohen, director of Carnegie Mellon's Laboratory for the Study of Stress, Immunity and Disease says.

Research was conducted separately in 1983, 2006 and 2009. The studies found that those with higher stress were women, people with lower incomes and those with less education.

Research also proved that as people age, stress decreases.

"Thirty-year-olds have less stress than 20-year-olds, and 40-year-olds have less stress than 30-year-olds," Cohen says, who has studied the relationship between stress and disease for 35 years.

Using the Perceived Stress Scale, or PSS, the studies utilized a measure Cohen and others created in 1983 to assess the degree to which situations in life are perceived as stressful. All respondents answered a series of questions designed to evaluate their stress levels. Higher scores indicate greater psychological stress.

Results show increases in stress in almost every demographic category from 1983 to 2009, ranging from 10 percent to 30 percent.

Not surprisingly, the study found that white, middle-aged men with college degrees and full-time jobs were the group most affected by the economic downturn. Cohen says that group's increase was almost double that of any other demographic group.

Physician Paul Rosch, president of the non-profit American Institute of Stress, based in Yonkers, N.Y., says this study is more credible than most stress surveys due to its scientific methodology.

The results all follow a logical progression, researchers say. When you compare the early 1980s to today, "economic pressures are greater, and it's harder to turn off information, and it's harder to buffer ourselves from the world," Spiegel says.

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