The True Measure

Historians looking to sum up 2020 will invariably use the word “catastrophe.” But for all its suffering, our annus horribilis brought with it a significant public health triumph: In 2020, for the first time in U.S. history, the number of citizens over age 65 rivaled that of children under 15. Worldwide, the average human life expectancy has doubled in the past century, largely due to advances in public health. Dean Linda P. Fried, MD, MPH, likes to say that public health has “raised the floor and the ceiling of health,” with reduced deaths in childbirth and infancy setting the stage for lives extended by vaccines, antibiotics, and other modern public health interventions. Research by Columbia Mailman School faculty is tackling challenges at both ends of the spectrum. If, as the saying goes, the true measure of a society can be determined by the way it treats its most vulnerable, then the School is truly measuring up.

Protecting the Littlest Lives 

As a young Columbia professor in the 1980s, Frederica Perera, MPH ’76, DrPH ’82, PhD ’12, studied how exposure to environmental contaminants could result in damage to DNA and eventual disease. A pioneer in molecular epidemiology, she was focused on detecting lung cancer at its earliest stages. She needed a control sample that would be as pure as one could get, so she settled on pristine cord blood. (“Because what could happen to a fetus?” she recalls thinking.) Perera was shocked to discover in her cord blood samples the same evidence of chemical exposure that she’d been observing in adults and in people with cancer. “That was a wake-up call,” she explains, and the moment she decided to focus her considerable energies on prenatal exposure to toxins. 

By 1998, Perera had founded the Columbia Center for Children’s Environmental Health (CCCEH), and she and her colleagues had begun enrolling more than 700 pregnant women from low-income neighborhoods in Northern Manhattan and the South Bronx in an effort to determine the effects of prenatal and early childhood exposure to urban pollutants on these historically marginalized communities. The heavy traffic and idling buses and trucks that were a staple in the neighborhoods, which are home mostly to Dominican American and Black families, suggested that pollution levels would be high, and Perera was concerned about the lasting impact the polluted air would have on the developing brains, lungs, and other vital organs. She and a team of investigators installed air monitors in the homes of study participants and convinced them to wear portable ones as they went about their day. (This last bit took some doing, as the first backpacks holding air monitors were rejected on account of their unsightliness. They were eventually replaced by Prada knockoffs sourced from Chinatown.) Working closely with community organizations, particularly WE ACT for Environmental Justice, CCCEH researchers have now been conducting interviews, collecting questionnaires, and amassing data based on the monitors and various biological measurements for 22 years. Some of those first babies now have kids of their own. In addition to studying diesel exhaust particulates and the polycyclic aromatic hydrocarbons that result from burning fossil fuels (like diesel, gasoline, and coal), the teams have gone on to investigate the impact of lead, mercury, mold, phthalates, tobacco smoke, pesticides, and home allergens related to mites, mice, and cockroaches, documenting links to neurodevelopmental problems, obesity, and asthma and other respiratory disorders along the way.

Andrew Rundle, MPH ’94, DrPH ’00, who as a graduate student worked on the original design and grant proposals for CCCEH, eventually led a team that showed that air-pollution exposure during pregnancy was associated with overweight (higher body mass index) in African American and Dominican American children. Rundle, a professor of Epidemiology, also has been comparing outcomes from vaginal births and cesarean deliveries to determine whether the relatively sterile environments involved with surgery might restrict newborns’ exposure to helpful microbacteria and compromise the microbiome in such a way as to result in excessive weight gain later in life.

CCCEH researchers are now looking into how maternal stress, often due to poverty and racism, can behave like some of the other pollutants they’ve studied to damage developing fetuses and babies.

Perera, who holds a PhD in environmental and social policy, founded CCCEH with a mission to inform public policy. “The idea was not to have this science going into a black hole in some peer-reviewed publication, but rather to inspire real-world change,” she says. Today, the team can point to successes from the local level to the international stage. Under the Bloomberg administration, the Center’s research was instrumental in New York City’s decision to begin a phaseout of the cheap, sludgy fuel oil that had long been common to low-income housing; its combustion produces damaging particles. Testimony at city-council and zoning-board meetings by Rundle, who also studies the impact of urban design on physical activity and diet, helped make it possible for supermarkets and grocery stores to open in neighborhoods formerly characterized as “food deserts.” In Poland, where Perera established a children’s cohort, her work with Polish colleagues at the University of Krakow has led to the replacement of coal-burning units in residential homes. In work led by associate professor of Environmental Health Sciences Deliang Tang, MD, DrPH ’96, she and their Chinese colleagues provided the Chinese government with evidence that babies born in the Chongqing municipality after the closure of its coal-fired power plant were healthier and performed better on cognitive tests than those born earlier.

Julie Herbstman, PhD, who in 2020 succeeded Perera as director of CCCEH, has gained national recognition for her work on flame retardants, including polybrominated diphenyl ethers, or PBDEs, the compounds once routinely added to car seats, couches, and other furniture. Her research showed that the PBDEs tended to leak over time, and that exposure to them resulted in impaired IQ and attention problems among children. Going up against the chemical companies that produced the compounds—as well as against Big Tobacco, which had helped convince fire-safety officials to back a standard that effectively required all furniture to be filled with the toxic compounds—Herbstman played a pivotal role in the eventual decision by the U.S. Consumer Product Safety Commission to advise manufacturers against the use of this class of compounds.

In the past year, Perera has shifted her focus to communicating the work of the Center and addressing the broader challenges presented by a changing climate. Her team recently used data collected during the COVID-19 shutdown in the spring of 2020 to extrapolate what lower levels of air pollution would mean over the next five years in terms of healthier birth weights and lower rates of asthma and other illnesses. They estimated the economic savings to be somewhere from $32 billion to $77 billion. Now, they are using their findings to advocate for a transition away from fossil fuels and to a renewable energy–based economy. Says Perera, “I’ve always had the idea that if we can bring the information together in a compelling way, we can make a difference.”

Riding A Great Gray Wave 

As a graduate of both Columbia College and the Vagelos College of Physicians and Surgeons, the gerontologist Robert N. Butler, MD, didn’t have to look far when he sought a new home for the International Longevity Center that he’d established in 1990. It didn’t hurt that the Columbia Mailman School counted as its leader one of the preeminent geriatricians in the country. When it opened in 2013, the Robert N. Butler Columbia Aging Center became the first universitywide hub for aging science and policy in the U.S. It is devoted to interdisciplinary research and education, as well as to amplifying the needs for aging equity as we all live longer lives. “We’ve shown in this country that if people are well-educated and well-resourced, and have lived in health-promoting environments with good medical care, they can live long lives with health,” says Fried, who serves as director of the Center and is also co-chair of the National Academy of Medicine’s Global Roadmap for Healthy Longevity Initiative. “We are, happily, aging societies. But our society was designed when life expectancy was in the 40s. We haven’t yet evolved our systems to match the opportunities and meet the needs.”

While Fried firmly believes that the country’s—and, indeed, the world’s—shifting demographic trends present enormous opportunities, she fears that policymakers “don’t yet know what to do” with the new dynamic. Ageism remains rampant, a reality underscored by the pandemic, during which politicians and other public figures have routinely dismissed older Americans as disposable and demonized them for dragging down the economy. Fried talks about a “third demographic dividend”—a new stage of development in which all ages will benefit from people living longer lives. “But unless we build the upside,” she warns, “you’re only looking at cost.”

The Columbia Aging Center is focused not just on resetting the public health agenda so that people worldwide live longer, healthier lives—its International Longevity Center USA is a leader of a global consortium developing policies, awareness campaigns, and interventions to better respond to aging populations—but also on actually building that upside, according to a new set of plans. Fried points to the work of associate professor of Sociomedical Sciences Kavita Sivaramakrishnan, PhD, whose book As the World Ages: Rethinking a Demographic Crisis examines how the global community has responded to aging and how countries have successfully mobilized programs used by local communities so that they can be scaled up or be relevant to other settings. Sivaramakrishnan explains: “For instance, in cities such as Chennai in South India, there are neighborhood-level networks of geriatric checkups and care by older people who take care of the oldest of the old. This approach is low in cost and encourages social cohesion.”

“Failure to adapt to aging is a risky strategy for a country,” notes John W. Rowe, MD, the Julius B. Richmond Professor of Health Policy and Aging and a member of the School’s Board of Advisors who also chairs the Aging Society Network, a consortium of scholars helping to prepare the nation for the challenges and opportunities posed by an aging society. “If we neglect to develop and implement effective policies, we will be left with a society rife with intergenerational tensions, characterized by enormous gaps between the haves and the have-nots, and unable to provide needed goods and services for any of its members.” 

Citing a 2005 study conducted in St. Louis that found that among adults aged 65 years and older, Black individuals living in urban areas became disabled 10 years earlier than suburban White individuals, Fried underscores the critical importance of addressing our vast inequalities. Assistant professor of Epidemiology Daniel Belsky, PhD, studies why socioeconomically disadvantaged populations face shorter health spans. Belsky has demonstrated that just as environmental toxins and pathogens affect the cellular properties of aging, with molecular-level changes eventually contributing to the development of diseases, so do poverty and psychological stress. Young adults who have been exposed to early-life poverty and/or were victimized as children by physical abuse, sexual abuse, neglect, or bullying showed a faster pace of biological aging.

Belsky has used samples from an existing study of prolonged caloric restriction in young, healthy people to test if this intervention, proven to slow aging in animals, can also slow the process at the organ system and cell level in humans. He and his team also are investigating how in utero undernutrition contributes to aging-related health decline. And they recently began analyzing samples from a trial of an anti-poverty intervention called Paycheck Plus in order to determine what, if any, impact that two-year cash-supplement experiment had on biological rates of aging.

Based on their findings, Belsky says, the researchers might then begin to consider what sorts of interventions could best extend the lives and health of our most disadvantaged citizens. “If money works, then a question will be, ‘Are there particular things that people who got money did that appeared to advantage them? Did they move to cleaner, greener neighborhoods? Did they take up different work? Did they report a reduction in stress?’” Such conclusions could help determine whether it would make more sense to intervene on the psychological experience of stress, for example, or on what people are eating, how often they’re moving their bodies, or where they live, and, in turn, could establish what society needs to do to create the conditions for healthy longevity for everyone.

Belsky and his team recently presented an innovation that could speed up the research process considerably in the future. Combining genomic data and machine-learning analysis, they have devised an algorithm that can quantify the pace of aging based on a single drop of blood. Not only do such samples summarize changes occurring across entire organ systems, but they also appear to be predictive of differences in the risk of death.

Also on the horizon: greater understanding of Alzheimer’s disease and other complex diseases associated with aging, thanks to work by researchers in Biostatistics. Iuliana Ionita-Laza, PhD, and Ying Wei, PhD, professors of Biostatistics, recently received a grant from the National Institute on Aging to use novel statistical methods that can be applied to massive, biobank-size datasets, using genetic data from tens of millions of genetic variants across the genome to identify variants associated with Alzheimer’s disease. Ionita-Laza has already identified several new genes associated with Alzheimer’s disease. Expanding the studies to include new methods could lead to new genetic findings with particular relevance to medicine development. 

Work taking place at Columbia Mailman School will ideally improve on the ability to identify those most at risk of age-related disease early enough to intervene. Among the interventions might be strategies for designing out loneliness and social isolation, which Belsky has shown is linked to premature aging. Innovations like Experience Corps, a program Fried co-founded in which older people with lifetimes of knowledge (and the desire to leave the world a better place than they found it) work with children in public elementary schools and enjoy health benefits as a result, could go along way to realizing some of those dividends. “Think about what it can mean for kids to be surrounded by intergenerational caring,” says Fried. “It changes their future.”

Jocelyn C. Zuckerman is the author of Planet Palm: How Palm Oil Ended Up in Everything—and Endangered the World. She is an alumna of Columbia University’s Graduate School of Journalism.