Income inequality killing Americans

A new study provides the best evidence to date that higher levels of income inequality in the United States actually lead to more deaths in the country over a period of years.

The findings suggest that income inequality at any one point doesn’t work instantaneously – it begins increasing mortality rates 5 years later, and its influence peaks after 7 years, before fading after 12 years.

“This finding is striking and it supports the argument that income inequality is a public health concern,” said Hui Zheng, author of the study and assistant professor of sociology at Ohio State University.

The study appears online in the journal Social Science and Medicine and will be published in a future print edition.

Many other studies have examined the impact of income inequality on mortality and have come up with mixed results, according to Zheng. But he thinks that this study overcomes problems in previous research by using a different data structure and statistical model (called a discrete-time hazard model).

Zheng used data from the U.S. National Health Interview Survey from 1986 to 2004 with mortality follow-up data from 1986-2006. His final sample included more than 700,000 people aged 30 and up.

The study measured income inequality using three different methods, including the most commonly used metric – the Gini coefficient, calculated by the U.S. Census Bureau. All three methods resulted in similar findings.

The Gini coefficient ranges in value from 0 (indicating complete equality, with everyone earning the same income) to 1 (complete inequality, with one person earning all income).

The Gini coefficient has been steadily rising in the United States in recent decades, from .403 in 1980 to .469 in 2010.

In this study, Zheng found that a 0.01 rise in the Gini coefficient increases the cumulative odds of death by 122 percent in the following 12 years. This is after taking into account a wide variety of factors that may also influence mortality, including a person’s age, gender, race, marital status, education, work status and family income.

“Income inequality has a substantial effect on mortality,” he said.

But if income inequality does indeed affect mortality rates, why have other studies found mixed results? Zheng reviewed 79 previous studies to look for the reasons. The 11 best studies looked at income inequality at a particular point in time to see how it affected mortality rates at a specified time later.

“But current mortality isn’t just affected by income inequality at one time, say 10 years ago. It is also affected by income inequality 9 years ago, and 11 years ago, and the current level of inequality, and so on,” he said.

In this study, Zheng was able to look at deaths in a particular year and control for income inequality for each of up to 21 years preceding the death.

“For the first time, we can clearly capture the long-term effect of income inequality on health,” he said. “Previous studies are likely to miss the effect if the mortality follow-up period is too short for income inequality to exert its impact or too long for income inequality to maintain its influence.”

Other scholars have hypothesized why income inequality may lead to higher death rates. One reason may be that, in countries with rising income inequality, the interests of the wealthy tend to diverge from the rest of society. The wealthiest people may push government for more services for themselves, rather than invest in public goods like education or affordable medical services – services that can affect health for the majority of people.

In addition, inequality reduces social cohesion and trust, which studies suggest is important to individual health.

Finally, inequality may create a culture of upward comparison, where many people see the lifestyles of the rich and feel they can’t live up to expectations. That can lead to negative views of themselves, frustration and depression, which have been linked to sickness and mortality.

“None of these negative factors caused by income inequality will have an immediate effect on chronic illness and mortality,” Zheng said.

“But over time they take a toll on health, which can eventually lead to sickness and death. That’s why this study found that it takes 5 years for the effects of income inequality to appear.”

These results also support findings from a 2009 study by Zheng that examined how income inequality affected Americans’ self-rated health. That study found that the dramatic increase in income inequality from 1972 to 2004 increased the odds of worse self-rated health by 9.4 percent. That study only looked at the instantaneous impact on self-rated health. The impact should be even larger if it had taken into account the long term impact, he said.

“The evidence is growing clearer that income inequality has a long-term detrimental impact on individual health and mortality,” he said.

The material in this press release comes from the originating research organization. Content may be edited for style and length. Have a question? Let us know.


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4 thoughts on “Income inequality killing Americans”

  1. Thomas: I agree with your assessment, but I hope you’re not with the whole Occupy bunch saying that capitalism is the issue. Back in the day, the market was much less restrictive than today. It was a lot easier to find a job before the government started messing things around.

    • Mike Walker,

      No, I’m not naive enough to believe that capitalism is the cause of the current state of affairs for the working man or woman. I do see how government “incentives” create more problems than they solve.

      In a very economically depressed area of Chicago, where I worked as a detective for eight years, a program came about that was a joint “job generator” from the fed, state and city gov’s. Basically, if you hired someone for a “new” job, during a period lasting a couple of years, you were allowed to take a double deduction for the wages paid. So a popular pizza chain opened up a take-out only store in this neighborhood and they stayed open for the time period and then they closed.

      So some working people had a job for two years, then not.

      I could see no difference in the economic activity in the neighborhood, comparing before and after. But that wasn’t my area of research, so it’s only observations.

      On the other hand, a very good friend of mine purchased a small plastic parts manufacturing company, with about 300 employees, most who lived within a half-mile of the factory. They turned the company around and needed more space to expand. There was a lot behind their factory, completely vacant, and had been for years. They approached the alderman about purchasing the lot, and were told that the lot was not for sale. Period. They inquired about any other assistance or loan programs, anything that might help them mitigate the expense of moving from their location, to another, larger place. They were told no, sorry, we can’t help.

      My friend had no problem with that. He went about his business, found a suitable location, in another town, in another state, in an industrial “neighborhood” created directly next to the electrical powerplant. The only real incentive that they recieved was about a 33% decrease in their electricity bll. That was a big enought savings to help them make the move.

      Oh, and the lot that wasn’t available to him? It was purchased by a Not-For-Profit agency, which then built a five story apartment building, and rented the units out to low-income elderly people from the neighborhood. All fo which is fine.

      Except, really, did it make sense to deny the 250 or so employees who were not willing to move, or to make the 1 hour commute (each way) a job? And of those who were not able to make the change, how many were not able to find work? And in twenty years, how many of them would need to have a building built by a “Not-For-Profit” agency (guaranteed by the government) to house them in their senior years?

      I don’t understand it. It is not logical, nor reasonable.

    • Dear Patti,
      I read your comment, with a breath of amazement. First, I commend you for working towards a greater understanding of the many factors influencing healthy living. Next, I’m impressed by the fact that you took a special interest in this particular study. And finally, I am truly amazed at the speed at which you can digest a complex issue, assess the validity of the study based upon some extremely deep analysis and then boldly state that the opinions of the author are: 1. contrived but foolish talk
      2. insincere and pretentious talk, example: “politicians’ claptrap”
      (in the sense of : something contrived to elicit applause): from clap + trap].

      However, I disagree with your assessment. I worked as a police officer in a large city for thirty-three years. I saw, first-hand, how our society has gradually changed from:
      A.) A place where a person with an average education, say a high school diploma, could carve out a decent living, to pay rent for their apartment, save enough to put a down payment on a condo or “starter house” in about five years time; pay for their groceries, and maintain the ten year old automobile they used to get to work and back.
      B.) A place where a person with an average education, a high school diploma or a general education degree, can earn barely enough to pay about one-half of the rent required for a small apartment, can never save enough for a down payment on a condo or house, can buy their groceries and depend upon others to car pool, to get to work and back.

      I also noticed that the increased hours which both mother and father had to work, to put food on the table for themselves and two children caused them to be absent from the home during crucial hours when the children needed the most guidance, support and encouragement, say to do their homework and to help them to feel safe.

      Without the direct supervision of their parents, SOME of these children grew up to drop out of school at the age of 16 or 15 or 14 years of age, then they were recruited into gangs to sell drugs and carry guns, and eventually ordered by their gang leaders to shoot someone or they would end up shot and killed.

      Now I concluded from this long-term “study” which I worked within, that the conditions of normal life have become a great deal more difficult for “the average person,” at the same time that the “average” wealthy person (those in the highest quintile, or top fifth of the income scale, has become wealthier and wealthier.

      The only objection that I have to the study is that it includes only physical health. It does not touch the decline in moral and psychological health of the wealthy class as they become more and more isolated from an meaningful interaction with “normal” people.

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