In the ultimate measure of health—how long you live—it makes a big difference where you live in the United States, especially if you’re poor.
Men in the bottom 5 percent of the income distribution who live in New York City, for example, can expect to live five years longer than men with comparable incomes in Gary, Indiana.
“These are really enormous differences across places,” says Raj Chetty, a professor of economics at Stanford University.
To place a 5-year life expectancy disparity in perspective, the Centers for Disease Control estimates that life expectancy in the United States would increase by just over three years if cancer was eliminated as a cause of death.
“You can think of the fact that there is a 5-year gap between Gary and New York as if low-income people in New York don’t get cancer at all while people in Gary do,” Chetty says.
Rich and poor
For the new study, published in the Journal of the American Medical Association, researchers used anonymous data on deaths from the Social Security Administration and more than 1.4 billion individual tax records from 1999 to 2014 to obtain more precise estimates than any previous research on the differences in life expectancies among income groups in the United States.
“Where you live matters much more if you are poor than if you are rich.”
Being richer is associated with living longer at every level of the income distribution. And the gap between the richest 1 percent and the bottom 1 percent in the nation is vast. At 40, the richest men can expect to live to 87 while the bottom 1 percent have a life expectancy of just above 72—equal to the average in a developing country like Sudan.
Women have longer life expectancies than men, but the gap between genders narrows substantially at higher income levels. Women at the top of the income distribution can expect to live close to 89. The life expectancy of women at the bottom is 79 years—a 10-year gap equivalent to the drop in longevity associated with a lifetime of smoking.
Moreover, inequality in life expectancy between the rich and poor in the United States widened during the 2000s. High-income people gained about 3 years of life expectancy while the poorest saw little to no improvement from 2001 to 2014. But this statistic masks broad differences at the local level.
In places like Birmingham, Alabama, the poor were gaining just as much in life expectancy as the rich overall (3 years over the period). But in other cities such as Tampa, Florida, the life expectancy of the poor was actually decreasing over the 2000s.
“We find very large differences across areas for the poor but very small differences across areas for the rich. Where you live matters much more if you are poor than if you are rich,” Chetty says.
After taking into account differences in life expectancy that stem from ethnic and racial composition, the study suggests some of the lowest levels of life expectancy for the poor were in the industrial Midwest.
Eight of the 10 states with the lowest levels of life expectancy for the poor formed a geographic belt from Michigan to Kansas, encompassing Ohio, Indiana, Kentucky, Tennessee, Arkansas, and Oklahoma. In contrast, the poor had significantly longer life expectancies in California, New York, and Vermont.
Do as the neighbors do
Differences in health behaviors seem to play a more important role in the findings than measures of health care coverage and access to medical care.
“The places with shorter life expectancy tend to be places with higher rates of smoking, higher rates of obesity, and lower rates of exercise,” Chetty says.
Local levels of income inequality and residential segregation by income did not seem to be associated with differences in health among the poor. Instead, measures of affluence, larger fractions of college graduates, higher share of immigrants, and greater government expenditures were strongly linked with longer life expectancy for the poor. The researchers found that poor people tend to live particularly long in cities like San Francisco and New York, which have high costs of living and highly educated populations.
“We don’t know exactly why that is, but what I find striking is that the results go against the view that the poor do better in cities that are more affordable with less inequality,” Chetty says.
It may be that these cities are often the first to enact public health policies such as smoking bans, restrictions on trans fats, or imposing taxes on sugary drinks—moves that affect the health of the poor as well as the rich.
It is also possible that people are influenced by others’ good habits. If there are more people around you who are exercising and eating well, you may spend less time sitting on the couch eating junk food.
The findings imply that the relationship between income and health is not set in stone and that there is significant room to improve the health of the poor by focusing on the issue at the local level. Health behaviors and why they vary from one area to another seem to be a particularly promising area for future research.
“There is a lot discussion about inequality and health in the US as a whole but I think that conversation should be occurring at the local level,” Chetty says.
The study’s findings also have implications for national policies like Social Security and Medicare. The fact that the rich have longer lifespans than the poor means that low-income people are paying into the system for a long time but don’t get to enjoy the benefits as long. This is particularly important to discussions of raising the retirement age.
“If we think about a policy like indexing the retirement age to life expectancy, we need to think hard about which life expectancy we are talking about. If we just use average life expectancy in the US, we are going to essentially start hurting the poor, especially in certain areas—like Detroit—relative to the rich,” Chetty says.
Researchers from MIT and Harvard University are coauthors of the study. The US Social Security Administration, the National Institutes of Health, the Social Sciences and Humanities Research Council of Canada, the Smith Richardson Fondation, and the Laura and John Arnold Foundation funded the work.
Source: Stanford University