Under similar stress, rich live longer than poor, study reports

The findings show that the combination of poverty and stress "is a bomb," said study lead author Dr. Antonio Ivan Lazzarino, clinical research associate at University College London. "Those people have really higher mortality, more than you would expect by just adding the two separate effects."

Researchers already know that stress and poverty take a toll on longevity. The new research aims to "study both stress and income to see how their combinations—low-low, low-high, high-low, high-high—affect mortality," Lazzarino said.

The research design doesn't specify how much longer someone may live if he's rich and stressed versus poor and stressed. And why wealthier people may tolerate stress better biologically is not well understood. Also, the study only found an association with wealth, stress and mortality, it didn't prove cause-and-effect.

For the study, published online Dec. 3 in the Archives of Internal Medicine, the researchers examined a database of more than 66,500 people in England who were 35 years or older between 1994 and 2004. The participants were questioned about their jobs—whether they were unskilled workers or held managerial jobs, for instance—and whether they had symptoms of anxiety, depression, low confidence or social dysfunction. None had cancer or heart disease at the start of the study, which followed participants for eight years on average.

After adjusting their statistics so they wouldn't be thrown off by factors such as age or gender, the researchers found that poor and stressed-out people died earlier.

Having more money seemed to serve as a buffer, even when wealthier people had high levels of stress. In the other direction, it seems that "low income amplifies the adverse effects of stress," Lazzarino said.

One expert wasn't surprised by the findings. Poorer people have fewer ways to combat stress, said Glyn Lewis, professor of psychiatric epidemiology at the University of Bristol in England.

"For example, if your car breaks down, then a wealthier person could afford to rent a new car or get their old one mended quickly or will have insurance for this," Lewis said. "It is much less stressful if you have the money to seek out alternatives."

The study authors suggest that wealthier people may have better ways to manage or contain their distress and more people around them who can help. Also, previous research has shown that the cardiovascular systems of richer people recover faster from acute stress, which might contribute less to long-term cardiovascular damage, the authors noted.

However, the study didn't document how stress levels changed over time, and the authors acknowledge that that is a limitation of their study.
Still, Lazzarino said the findings might help researchers refine tools for stress measurement. "Since we know that stress is very bad for your health, one could argue that every person on the planet should do tests to measure his/her own stress and that family doctors should screen all patients they have for stress," he said.

"However, this strategy may not be cost-effective," he added. "We say that if you specifically target low-income people, stress screening may be very useful and cost-effective."

More information: For more about health and stress, visit the U.S. National Library of Medicine.

Journal reference: JAMA Internal Medicine

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