Many researchers feel that no marker reflects the health and wellbeing of society better than life expectancy. While the United States has come a long way over the past two centuries, estimated U.S. life expectancy has declined sharply and steadily since 2010 – an alarming trend that has captured the interest of Arun Hendi, CHW affiliate and assistant professor of sociology and public affairs at Princeton University.

In a recent interview, Hendi shares his fascination with population dynamics while highlighting some of his latest research examining geographic, socioeconomic and racial inequalities in health and mortality.

Q. Tell me about your path to becoming a demographer. What sparked your interest in the field?

A. My career as a demographer was inspired by a series of serendipitous events. The earliest one occurred when I was 11 or 12 years old and came across this amazing documentary that presented Japan’s aging population as a social problem. They talked about pension fund solvency, caregiving requirements, health care spending, and political issues associated with an older population. The program included interviews with a bunch of demographers, which was my first inkling that people study populations as an occupation.

Later on, in high school, I took some math classes where I ran into predator-prey systems and differential equations for population analysis. That was probably my first exposure to the use of mathematics for addressing social problems.

The third, possibly most formative experience happened as an undergraduate at the University of Pennsylvania. The university’s Population Studies Center offered a course called “Health of Populations” taught by a preeminent demographer by the name of Samuel Preston. I never took that course, but my wife (who was my girlfriend at the time) did. I completed all of the readings along with her and thought this class, which was tied to health and health inequities, was the neatest thing in the world.

Q. I see that you received an undergraduate and Master’s degree in economics before earning an AM and Ph.D. in demography and sociology. What inspired the switch in discipline?

A. When I graduated from college, the great recession had just started, the financial collapse had just occurred, and there were very few jobs available. Part of the reason I pivoted away from economics and toward sociology and demography was a general dissatisfaction with looking at things like price mechanisms and macro-economic financial models. At that time, a lot of folks – myself included – were thinking about the broader issues facing the country. So I took stock of my ambitions and realized that I was most interested in questions of equity, such as how immigrants are faring in the country, as well as the composition of populations, increasing ethnic and racial diversity, and outcomes that result when different groups interact. While these issues relate to economics, and all of the social sciences, they are central to sociology. 

Rather than focusing on the minutia or nitty-gritty, sociologists and demographers zoom out to look at the big picture. We examine the social trends that have been underway for decades and how they’re shaping outcomes – in my case often related to health, but also related to other outcomes such as fertility, migration, or aging. I find that context fascinating.

Q.  To follow up on that point, why is much of your research concentrated on inequalities in health? 

A. On an intellectual level, I view health inequalities as a puzzle. Life expectancy in the U.S. has improved over the long run, even though it’s not doing well right now. In the 19th century, Americans could expect to live about 45 years; today they can expect to live around 80 years. But at the same time that we’ve seen great improvements in life expectancy, we’ve seen dramatically widening gaps between population subgroups. In particular, the most educated group of people, college graduates, are experiencing robust gains while people without a high school diploma haven’t experienced any gains at all. On the one hand, we have this overwhelmingly positive story of human progress, while on the other hand we have a starker story about the unequal distribution of that progress. This dichotomy has propelled my curiosity about changing population dynamics in the U.S. and their influence on health inequalities.

On a personal level, a lot of my childhood was spent observing inequalities. For example, when I was in elementary school, I can remember seeing kids on the school bus coating their lips with cooking grease in the winter months because they couldn’t afford lip balm. Then I had the opportunity to attend a different school in a different neighborhood and saw the other side of things. It became very apparent to me that not everyone came from the same situation, which affected me deeply.

Q. After launching your career at University of Southern California, you arrived at Princeton in 2018. What led you here and inspired your affiliation with the Center for Health and Wellbeing?

A. I was a research scientist at USC’s Center for Economic and Social Research when I learned that SPIA [Princeton’s School for Public and International Affairs] was hiring a demographer with the opportunity to affiliate with the Office for Population Research [OPR]. OPR is the oldest population studies center in the country and, in fact, a lot of modern demography was born at Princeton. The prospect of working here and shaping 21st century demography was very appealing.

Princeton is a wonderful place to be as a health researcher because of outfits like the Center for Health and Wellbeing, which I found during my first year on campus. As part of my role, I was a reader for a fascinating senior thesis on rural hospital closures. The advisor for that thesis was Professor Heather Howard, who thought that I might be a good fit for CHW. What I like most about the center is its strong interdisciplinary focus on health and health policy.

Q.  One of your recent papers examines trends in non-Hispanic white mortality in the U.S. by metropolitan and non-metropolitan status and region between 1990 and 2016. Why did you choose this topic?

A. There’s a lot of concern, at the moment, about the status of rural, non-metropolitan parts of the United States because they’re viewed as areas in decline – not just in terms of health. They are areas which are becoming deindustrialized (or weren’t industrialized in the first place), are increasingly dependent on government transfers, where schools and hospitals are closing, and are generally undergoing great change. Broadly, while metropolitan areas are seen as improving, non-metropolitan areas are seen as getting worse. For example, we now have more smokers in rural areas than urban areas, a reversal of the previous trend. I wanted to understand what was happening and why.

Q. What was most striking about your findings?

A. Our most significant finding was an urban-rural divergence in life expectancy trends. Our study showed that during this time period (1990 through 2016) life expectancy among non-Hispanic whites – and really among all racial and ethnic groups – increased tremendously in large, central metros while it basically flatlined in non-metropolitan areas.

To dig deeper, we looked at causes of death and found a strong link to health behaviors… things like cigarette smoking and drug and alcohol use. So one of our tentative conclusions was that health behaviors, on average, are getting better in metro areas and worse in non-metro areas.Other big drivers of rising mortality in rural areas, as identified by our study, include cardiovascular disease, respiratory illnesses (which are tied to factors like cigarette smoking) and nervous system disorders like Alzheimer’s disease. At the same time, on the urban side, we saw really big reductions in homicide and smoking-related causes of death and improvements in cardiovascular health. Together, these dynamics contributed to geographic inequalities in health and mortality, particularly among women and younger adults.

Q. Why did those populations suffer the most?

A. Part of the reason we saw this uptick in mortality in younger people and women was due to the opioid epidemic. While we’ve had drug epidemics in the past, earlier epidemics, such as the heroin epidemic, tended to be concentrated in urban areas. The opioid epidemic is more evenly distributed across geography and discriminates less between men and women.

Q. Has this study prompted further research? Did it raise additional questions that you hope to answer?

A. Yes, for sure. To put things into context, there are two different ways of thinking about spatial inequality in health. One way is that the place where you live has a direct effect on your health. The other way of thinking about it is that the health of an area is equal to the average levels of health of the people who live there; in other words, the properties of the place itself are not important health determinants.

Going forward, I’m interested in how much of the urban-rural divergence is linked to migration. Over the last few decades, an increasing number of people have been moving from rural areas to urban areas. Are health inequalities occurring because really healthy people are moving to metros and suburbs while really unhealthy people are left behind, or does geography impact their health?

Q. What else are you working on now? 

A. In addition to the research we just talked about, which is ongoing, I have two newer projects related to health.

The first project examines Black-white gaps in life expectancy. In 1990, Black men lived eight fewer years, on average, than white men. That difference has been cut in half. The Black-white gap today is closer to 3.5 to 4 years, which is monumental progress yet relatively few people are studying this. This project is still in its early stages, but my first paper shows that Black men experienced improvements in life expectancy across the socioeconomic spectrum. Additional research will tell a more complete story.

The other project looks at immigration and mortality. Since 1965, the United States has seen a large influx of immigrants. Immigrants tend to be healthier than native U.S. citizens, so it stands to reason that as the proportion of immigrants grows, the country’s general population should become healthier. That hasn’t happened. The U.S. has not experienced significant improvements in health or mortality in the last decade. How can this be the case?  I’ve started my research and part of what we’re finding is that immigrants have seen improvements, but people born in the U.S. have not. This is another divergence and inequality story, but it’s also a warning sign. Something is going wrong with our native-born population that we need to investigate.

Q. Has the pandemic substantively influenced any of your current or forthcoming work?  For example, Covid has exposed and exacerbated socioeconomic and racial inequalities with regard to health, and there are clear geographic differences when it comes to infection, vaccination and mortality rates. Are there any issues or dynamics that you’re thinking about?

A. With regard to Covid, the big question in my mind concerns what will happen when the pandemic is over. Hundreds of thousands of Americans have died and millions of people have been infected. We don’t know how those factors will shape health and mortality in the future.

There are a couple of possibilities. One is that health and mortality improve enormously because the people who died during the pandemic tended to have pre-existing conditions and were generally older and less healthy than the rest of the population. This could mean that the remaining population, on average, becomes healthier post-pandemic – not because of anything attributable to our country or health care system, but just because of this selective mortality. The other possibility is that the population could get significantly less healthy because even though a lot of people died during the pandemic, a lot of people survived and we still don’t know what the long-term effects, or even the short-term effects, of Covid will be. For example, we don’t know if survivors will have issues with lung functioning later in life, or whether the continued presence of Covid will lead to a new, more detrimental disease environment.

Furthermore, groups like Blacks and Hispanics were hit significantly harder than other racial and ethnic groups. So these sorts of effects will manifest even more strongly within those populations, creating inequalities.

We have to be aware and vigilant about what’s happening during and after the pandemic because it will influence how we understand and address population health in the future.

Q. Are you teaching any health-related courses upon your return from sabbatical this fall?

A. I’m not teaching this fall, but I am teaching SPIA 330, “Population, Society and Public Policy,” in the spring. We’ll be covering a lot of health-related issues, studying things like mortality transitions, reproductive health, racial and socioeconomic inequalities in health, and how immigrants shape the health of populations. It’s a really interesting and useful class for all students interested in health and population dynamics.

Q. Do you have any advice for students considering a health-focused career, whether it’s through sociology, economics, demography or another discipline?

A. I have a few bits of advice. The first is to try to take some courses in statistics or some type of quantitative, data-oriented field. The world is becoming a more data-oriented place, so even if you don’t end up doing data analysis as part of your career, it’s helpful to know what sorts of assumptions influence health statistics.

Also, read broadly. Right now, what you have in spades is time. The best thing you could do is read a lot of substantive work, and that includes more than just research. Some of the most interesting things that I read related to health are printed on the pages of The Washington Post, The New York Times or The Wall Street Journal.

And nurture your interests. Students have a tendency to focus on one thing because, in our society, we have to specialize to get ahead. But if you build up your knowledge base and expand your thinking, you give yourself more options for your future career.

Q. It’s always fun to end these interviews with a bit of trivia. Do you have any hobbies or talents that might surprise your colleagues or students?

A. I’ve got two things. The first one is that I’m a pretty decent flutist… I’ve been playing the flute since I was eight years old. I’m also an avid baker. In fact, when I was in grad school, I was known for bringing demography-themed baked goods to our office parties. I don’t think any of my students or colleagues would have guessed that about me!