Globally, tobacco kills 5 million people each year, about 8.8 percent of all deaths. Image: iStockphoto.com
On January 11, 1964, U.S. Surgeon General Luther Terry issued an official warning that smoking cigarettes can kill you. The report “hit the nation like a bombshell,” Terry later recalled. “It was front page news and a lead story on every radio and television station in the United States and many abroad."
Nearly 50 years later, however, more than 45 million American adults still smoke, more than 8 million are living with a serious illness caused by smoking, and about 438,000 Americans die prematurely each year as a result of tobacco use, according to the CDC.
The anti-tobacco movement is just getting under way in much of the developing world. Globally, tobacco kills more than 5 million people each year, accounting for about 8.8 percent of all deaths, according to the Tobacco Atlas. If current trends continue, tobacco will kill 7 million people annually by 2020 and more than 8 million people by 2030, most of them in low- and middle-income countries. (The Tobacco Atlas is produced by the World Lung Foundation and the American Cancer Society.)
“Nicotine use is a complex addiction,” said Gregory Connolly, director of Harvard’s Center for Global Tobacco Control, during a recent health conference held at Emory. If you inject someone with nicotine, you can’t make them dependent on it the way you can with heroin or cocaine, he explains. Nicotine dependency is driven by a range of factors including ease of use, chemo-sensory cues, activation of the dopamine-reward pathway and learned behavior.
Treating individuals is helpful in the short-term, but policy measures that remove smoking from the social norm are better in the long-term, Connolly said.
“Kids do what adults do,” he said. “You really have to de-normalize the behavior and take away the social benefits.”
On January 1, Emory became a tobacco-free campus. Smoking and all other forms of tobacco use are now prohibited on all Emory University and Emory Healthcare properties. More than 580 U.S. colleges and more than 2,800 hospitals and health-care organizations have adopted similar policies.
At least on U.S. college campuses, smoking is become a harder habit to continue.
"Genetic studies may help reduce some of the stigma society has against substance use disorders, while also making treatment more accessible," says Victoria Risner, first author of the new study on nicotine dependence, who did the work as an Emory undergraduate.
By Carol Clark
Some people casually smoke cigarettes for a while and then stop without a problem, while others develop long-term, several packs-per-day habits. A complex mix of environmental, behavioral and genetic factors appear to raise this risk for nicotine dependence.
Studies of groups of twins suggest that 40 to 70 percent of the risk factors are heritable. Until recently, however, studies have only explained about 1 percent of the observed variation in liability to nicotine dependence, using a genetic score based on how many cigarettes a person smokes per day.
A study led by psychologists at Emory University offers a new model for examining this genetic risk. It leveraged genome wide association studies for a range of different traits and disorders correlated with nicotine dependence and explained 3.6 percent of the variation in nicotine dependence.
Higher polygenetic scores for a risk for schizophrenia, depression, neuroticism, self-reported risk-taking, a high body mass index, alcohol use disorder, along with a higher number of cigarettes smoked per day were all indicators of a higher risk for nicotine dependence, the study found. And polygenetic scores associated with higher education attainment lowered the risk for nicotine dependence, the results showed.
“If you look at the joint effect of all of these characteristics, our model accounts for nearly 4 percent of the variation in nicotine dependence, or nearly four times as much as what we learn when relying solely on a genetic index for the number of cigarettes someone smokes daily,” says Rohan Palmer, senior author of the study and assistant professor in Emory’s Department of Psychology, where he heads the Behavioral Genetics of Addiction Laboratory.
“What we’re finding,” Palmer adds, “is that to better leverage genetic information, we need to go beyond individual human traits and disorders and think about how risk for different behaviors and traits are interrelated. This broader approach can give us a much better measure for whether someone is at risk for a mental disorder, such as nicotine dependence.”
Rohan Palmer heads the Department of Psychology's Behavioral Genetics of Addiction Laboratory that is developing new methods to better understand what makes people vulnerable to substance use disorders.
“All of the traits and diseases we looked at are polygenic, involving multiple genes,” adds Victoria Risner, first author of the study, who did the work as an Emory undergraduate majoring in neuroscience and behavioral biology. “That means that millions of genetic variants likely go into a complete picture for all of the heritable risks for nicotine dependence.”
The researchers hope that others will build on their multi-trait, polygenetic model and continue to boost the understanding of the risk for such complex disorders. “The more we learn, the closer we can get to one day having a genetic test that clinicians can use to inform their assessment of someone’s risk for nicotine dependence,” Palmer says.
Although the hazards of smoking are well established, about 14 percent of Americans report daily use of tobacco. Around 500,000 people die each year in the United States from smoking or exposure to smoke, and another 16 million live with serious illnesses caused by tobacco use, including cancer, cardiovascular disease and pulmonary disease. While the toxic chemicals produced during smoking and vaping are what cause harmful health effects, it’s the addictive component of nicotine that hooks people on these habits.
Risner worked on the current paper for her honors thesis. “Nicotine dependence was interesting to me because the vaping scene was just arriving while I was an undergraduate,” she says. “I saw some of my own friends who were into vaping quickly becoming dependent on it, while some others who were using the same products didn’t. I was curious about the genetic underpinnings of this difference.”
The project leveraged genome-wide association studies for a range of traits and disorders. The researchers then looked for matching variants in genetic data from a national representative sample of Americans diagnosed with nicotine dependence. The results showed how polygenetic scores for the different traits and disorders either raised or lowered the risk for that dependence. The number of cigarettes smoked per day, self-perceived risk-taking and educational attainment were the most robust predictors.
The multi-variant, polygenetic model offers a road map for future studies. A clearer picture of heritability for nicotine dependence, for instance, may be gained by adding more risk associations to the model (such as nicotine metabolism) and clusters of polygenic traits (such as anxiety along with neuroticism).
“As we continue to zero in on who is most at risk for becoming nicotine dependent, and what inter-related factors, whether genetic or environmental, may raise their risk, that could help determine what intervention might work best for an individual,” Palmer says.
“Just a few decades ago, it was not well understood that nicotine dependence could have a genetic component,” Risner says. “Genetic studies may help reduce some of the stigma society has against substance use disorders, while also making treatment more accessible.”
Risner graduated from Emory in 2019 and is now in medical school at the University of North Carolina, Chapel Hill. This summer, she’s applying the coding and analytical skills she learned at Emory to conduct research into genetic factors that may raise the risk for pre-term births.
Emory co-authors of the Nicotine & Tobacco Research article include graduate student Lauren Bertin; post-doctoral fellow Chelsie Benca-Bachman; and Alicia Smith, associate professor in the School of Medicine. Additional authors include researchers from the University of Helsinki; Brown University; the Providence VA Medical Center; the Jackson Laboratory in Bar Harbor, Maine; Purdue University; and the University of Colorado at Boulder.
The work on the Nicotine & Tobacco Research article was funded by the National Institute on Drug Abuse and the Academy of Finland.
“I’ve been affected by smoking since the day I was born,” says David Latov, a first-year medical student at Emory. “I never got to meet my grandpa on my mom’s side because he smoked his entire life and died of lung cancer when she was seven months pregnant with me.”
“The message isn’t that if you smoke you’re a bad person,” Latov says. “We need to acknowledge that smoking has real consequences and that everyone’s affected, not just the people that smoke.”
Linda Rosen, a business office manager at Emory’s Wesley Woods Center, recently graduated from the university’s smoking cessation program: For the third time.
“I learned the hard way that I can’t smoke ‘sometimes,’” Rosen says. “I really now am a non-smoker.”
An epiphany for her was writing a letter to cigarettes. “It was basically a good-bye letter, which was painful and heartfelt because smoking had been there for me,” Rosen says, adding that she is glad to finally feel free of the need to light up.
“One of the things that people often don’t associate with smoking is the environmental impacts,” says Ciannat Howett, director of Emory’s office of sustainability.
“Smoking is the leading cause of deforestation,” she says. “In Brazil alone, about 60 million trees every year are consumed just for tobacco production. “
Tobacco requires a lot of chemicals and fertilizer that lead to ground water and surface water contamination, she adds. “Cigarette butts alone are highly toxic and non-biodegradable. Every year about 1.7 billion tons are contributed to our oceans, rivers and streams.”
Higher taxes and smoke-free policies are reducing smoking among mothers-to-be, a new study by Emory University finds. The results will be published by the American Journal of Preventive Medicine.
The researchers evaluated smoking bans and taxes on cigarettes, along with the level of tobacco control spending, and found that state tobacco control policies can be effective in curbing smoking during pregnancy, and in preventing a return to smoking within four months on average, after delivery.
"We know from prior research that nearly one-fourth of all women in the United States enter pregnancy as smokers and more than half continue to smoke while they are pregnant which results in excessive healthcare costs at birth and beyond," says lead investigator Kathleen Adams, associate professor in the department of health policy and management at Emory’s Rollins School of Public Health.
"This is one of the first studies of pregnant women's smoking in the new era of more restrictive state tobacco control policies, and we found a sizable increase in the quit rate. In addition, tax policies appear to be effective in keeping these women from relapsing in the first few months postpartum, and the implementation of a full workplace smoke-free policy also increases quits."
Sara Markowitz, associate professor of economics at Emory University co-authored the study.
Investigators determined that a $1 increase in taxes and prices increases the probability of quitting by the last three months of pregnancy by 4.8 percentage points – from 44.1 to 48.9 percent. The probability of having sustained nonsmoking four months after delivery is increased by 4.2 percentage points or from 21.3 to 25.5 percent, with a $1 increase in real taxes. A full ban on smoking at private worksites increased the probability of quitting smoking during pregnancy by 4-5 percentage points.
Erik Nesson, an Emory doctoral candidate in health economics, was seeking detailed data for his dissertation into how both heavy and light smokers respond to tobacco control policies.
Turns out, his timing couldn't have been better.
The Atlanta Census Research Data Center (ACRDC) opened last fall within a secure computer room at the Federal Reserve Bank of Atlanta to provide restricted data for social, economic and health research.
Now, Nesson joins the first wave of Emory researchers to be granted a rare opportunity — the chance to study a virtual smorgasbord of government microdata not readily available to the general public.
From economic, business, trade and labor data to household and crime surveys, health statistics and manufacturing reports, the available material "goes far beyond what you would immediately associate with census data," says Nesson, who describes working at the center as "a nerd's trip to Nirvana."
Sifting through national health data, Nesson found that light smokers weren't really changing their behaviors, but heavy smokers were — reducing the number of cigarettes they smoked, but also inhaling more intensely and switching brands, so the level of nicotine in their systems never really changed.
Access to restricted data, he says, made all the difference.
"It's a huge competitive advantage," Nesson explains. "It's hard enough to think of ideas for dissertations, things no one has done before or ways to improve on what people have done before. The ridiculous amount of data they have [at the ACRDC] will be a great recruiting tool for people interested in really any field."
Research trips to the next closest centers — in North Carolina or Maryland — would cost both time away from the classroom and travel funds, says David Frisvold, assistant professor of economics at Emory, who is working with the ACRDC for research into soft drink taxes and childhood obesity.
Although the data Frisvold needs are available elsewhere, he has had to pay steep fees to access what he can now examine at the ACRDC at no cost. "It makes a big difference," he says.
Data at the center are restricted primarily due to privacy concerns. Researchers must submit to a rigorous background check, receive data security training, and submit a formal application to win approval for their projects in order to work in the highly secure computer lab.
When the ACRDC opened, Frisvold was already studying how sales taxes on soft drinks —a strategy to reduce childhood obesity and raise revenue for budget-strapped states — affect childhood obesity. He not only needed regional tax information, but a complete portrait of consumers: where people lived, their height, weight and soft drink consumption patterns.
With access to restricted data, "we have a very precise estimate on the impact of soft drink taxes on body mass index," says Frisvold, whose project also involves colleagues at Yale University and Bates College.
Some of the risk for repeated cannabis use into adulthood can be attributed to the genetic effects of neuroticism, risk tolerance and depression, the study found. "While this work marks an important step in identifying genetic factors that can increase the risk for cannabis use, a substantial portion of the factors that raise the risk remain unexplained," says Emory psychologist Rohan Palmer.
By Carol Clark
While some youth experiment with marijuana but don’t go on to long-term use, others develop a problematic pot habit that continues into adulthood. A major new analysis shows that at least a small portion of the risk for developing into an adult marijuana user may be related to inherited behaviors and traits that appear during adolescence.
The journal Addiction published the findings by researchers at Emory and Brown University.
“Our analysis suggests that some early adolescent behaviors and traits — like depression, neuroticism and acting out — can be indicative for cannabis use later in life,” says Rohan Palmer, senior author of the paper and assistant professor in Emory’s Department of Psychology, where he heads the Behavioral Genetics of Addiction Laboratory.
“Decades of research has shown that behaviors can have a genetic component,” adds Leslie Brick, lead author and assistant professor in the Department of Psychiatry and Human Behavior in Brown’s Alpert Medical School. “And while there is not one genetically-influenced trait that determines whether you’re going to be a long-term cannabis user, our paper indicates that there are polygenic effects across multiple inherited behaviors and traits that show a propensity for increased risk.”
Brick, a long-time collaborator with Palmer, also holds an adjunct faculty appointment in Emory’s Department of Psychology.
The Transmissible Liability Index is a well-known measure for a constellation of heritable traits that may appear during the developmental years that are associated with the risk of a substance use disorder. For the current paper, the researchers wanted to tease out which of these heritable characteristics might be associated with repeated marijuana use later in life.
“Cannabis use has been less studied than tobacco and alcohol,” Palmer says. “For one thing, it’s harder to get people to answer detailed questionnaires honestly about cannabis, since it’s an illegal substance. And it’s also much more difficult to standardize the amount of cannabis consumed, as compared to cigarettes and liquor.”
Cannabis use, however, is widespread among adolescents and young adults. In 2018, more than 35 percent of high school seniors surveyed reported having used marijuana during the past year and more than 20 percent reported doing so during the past month, according to the National Institute on Drug Abuse (NIDA).
As cultural norms have shifted, including the legalization of marijuana for adult recreational use in many states, teens’ perceptions of the risks of marijuana use have declined.
Those risks, however, are real.
“Adolescence is a major period of brain development,” Brick says. “In fact, our brains don’t stop developing until we are around 25 years old. Research indicates that cannabis has some major impacts on our biology, although its full effects are still not well understood.”
The researchers drew data from the National Longitudinal Study of Adolescent Health, or Add Health, which includes a nationally representative sample of 20,000 adolescents in grades 7 to 12 in the United States who have been followed into adulthood. Comprehensive data from early adolescence to adulthood was collected on health and health-related behavior, including substance use, personality and genetics.
For the current paper, the researchers identified a large homogenous subgroup of individuals from the Add Health study, about 5,000 individuals of European ancestry, for their final analytic sample. They then leveraged existing genome-wide association studies to examine whether certain heritable behavioral traits noted during adolescence were associated with the Transmissible Liability Index, and whether any of these traits were also associated with risk for later cannabis use.
The results showed that a small portion of the risk for repeated cannabis use into adulthood can be attributed to the genetic effects of neuroticism, risk tolerance and depression that can appear during adolescence.
“While this work marks an important step in identifying genetic factors that can increase the risk for cannabis use, a substantial portion of factors that raise the risk remain unexplained,” Palmer says. “We’ve shown how you can use existing data to assess the utility of a polygenic risk score. More studies are needed to continue to identify unique genetic and other environmental sources for the risk of long-term, problematic use of cannabis.”
“Better understanding of what behaviors and traits may give someone a pre-disposition for long-term cannabis use gives us a better shot of identifying those most at risk so we can home in on effective interventions,” Brick says.
A major limitation of the current study, the researchers add, is that it focused on individuals of European ancestry, because no sample size large enough for the genome-wide analysis was available for other ancestral groups.
Co-authors of the study include the following members of Emory’s Behavioral Genetics of Addiction Laboratory: Graduate students Lauren Bertin, Kathleen Martin and former undergraduate Victoria Risner (now an Emory alum); and Chelsie Benca-Bachman, associate director of research projects in the lab.
The work was supported by an Avenir grant from the National Institute on Drug Abuse.
People who are flourishing – both feeling happy and functioning well in their lives – are 60 percent less likely to die prematurely, finds a major study that followed more than 3,000 U.S. adults over 10 years.
The results, published in the American Journal of Public Health, applied to both men and women of varying ages, races, weights and socio-economic status.
“We’ve shown that, even when you factor in many other variables, if you are flourishing you have a dramatically lower risk of premature mortality, no matter what the cause of death,” says lead author Corey Keyes, a sociologist at Emory University and a pioneer of positive psychology.
The data for the analysis drew from the Midlife in the United States Study, which measured baseline positive mental health of the participants in 1995, and followed up in 2005. The ages of the participants spanned 25 to 74 at the beginning of the study, and 35 to 84 at the conclusion.
In the baseline survey, the participants were asked if they had suffered within the past year from depression, panic disorder or generalized anxiety, conditions that have been associated with a higher risk of premature mortality. They were also assessed for emotional happiness, or simply feeling good, and for whether they were functioning well in life, or flourishing. The term flourishing encompasses factors such as managing stress, achieving intimacy with others, working productively and making a contribution to society.
Nearly 50 percent of the study participants, who were representative of the general population, met the criteria for sufficiently high emotional well-being. Only 18 percent, however, were flourishing, meaning they met the full criteria of sufficiently high emotional well-being, combined with sufficiently high social well-being.
“You need both of these qualities for complete happiness,” Keyes says.
A total of 6.3 percent of the participants died during the study period. The odds ratio for mortality was 1.62 for adults who were not flourishing, relative to participants with flourishing mental health.
“What was most amazing to me was that the results held for all ages,” Keyes says. “Even late in life, if you are flourishing you are significantly less likely to die prematurely.”
Tobacco use and physical inactivity, behaviors associated in previous studies with people who have lower levels of emotional well-being, may partially explain how positive mental health affects mortality, Keyes says.
“We focus so much of our national health resources on treating mental illness, when it’s actually the absence of well-being that is getting to us,” Keyes says. “It may be common sense, but it’s uncommon public policy to invest more in promoting well-being.”
Graduate student Daniella Cicka, left, and senior Rina Lee, in the field in South Florida, collect a DNA sample from a plant species.
By Carol Clark
Adam Mackie will never look at a red maple the same way. “Native Americans made an infusion from the tree’s bark to treat gunshot wounds,” says Mackie, a senior majoring in biology. “It was also used to treat bug bites.”
Stachys floridana
Mackie is one of six Emory students who spent a recent alternative spring break in the field in rural South Florida. The students looked for plants used in indigenous medicine in the past, and collected specimens for the Emory Herbarium, under the guidance of medical ethnobotanist Cassandra Quave. They learned to identify endemic plant species in the wild, how to dig deep roots out of the thick mud of a marsh – even how to harvest and cook a swamp cabbage and make a mean guacamole.
"The best part was learning about plants from local people who knew how they were traditionally used," Mackie says.
Florida rancher Bob Brewer spent several days with the students in the field, introducing them to the gopher tortoise, a keystone species, and pointing out plants such as a thorny vine of smilax, which the locals call pipe briar.
We kept pulling and pulling on the stem," Mackie says, "and finally we got to this big tuber. He told us that old-timers used to hollow out these tubers to make pipes for smoking tobacco."
“Plants teach students to be more aware and appreciative of the natural world,” says Quave, a professor in Emory’s Center for the Study of Human Health and the School of Medicine’s Department of Dermatology. Quave’s lab researches how traditional uses of plants can inform modern medicine. Interviews with traditional healers in rural Italy, for instance, led to her recent discovery that the leaves of the European chestnut tree contain ingredients with the power to disarm dangerous staph bacteria without boosting its drug resistance.
HERBARIUM NEEDS YOUR GREEN TO GROW
The Emory Herbarium, founded in 1949 by members of the biology department, was closed for decades, and its collection of more than 20,000 specimens was kept in storage. The facility, which recently reopened in the Rollins Research Center, needs $10,000 to help restore and annotate some of its damaged specimens, including rare plants in the Granite Rock Outcrop Collection, which grow in the vernal pools of Arabia Mountain and Stone Mountain. The funds will also support digitizing the specimens so they can be posted online and accessed from around the globe. Check out the Herbarium’s Momentum fundraising campaign to learn how to contribute.
A graduate of Emory herself, Quave found her career path after she went into the Peruvian Amazon as part of a tropical ecology class in the department of environmental sciences.
“When I first get students in the field, they look at a meadow and just see what looks like overgrown grass. It’s like they have blinders on,” Quave says. “Then the blinders come off and they begin to use their ‘plant goggles.’ They start seeing the world in a new way.”
Jennifer Ko, a freshman, grew up in Manhattan and considered herself a city girl. That view was broadened somewhat, as she recounted in a blog post about the trip on the Center for Human Health web site. “I am no longer scared of laying down on the grass and, by the end of the trip, even embraced dirt,” she wrote.
Seniors Jessie Cai and Rina Lee prepare to press an epiphytic air plant from the Bromeliaceae family for deposit in the Emory Herbarium.
Ko also learned to spot and collect specimens such as the frilly white plume of Saururus cernuus (lizard’s tail), deep in a swamp.
“The Choctaw and Creek Indians called this plant ‘widow’s medicine’ because they used it in a tea to help the bereaved get over their loss,” Quave says.
She pulls a thick book, “Florida Ethnobotany,” off a shelf in her office to show a picture of widow’s medicine and a flattened sprig of yellow flowers falls out from the pages. “Oh, that’s a neat little Hypericum I collected,” she says, using the Latin name for St. John’s wort.
Ladyfinger bananas
The students rose before dawn and worked 12-hour days while in Florida. They explored scrub pine forests filled with 150-year old trees, still bearing what old-timers call “cat-facing” marks:” V-shapes cut into the bark during the 1800s to harvest turpentine. They took an airboat ride up the Peace River – the habitat of roseate spoonbills, bald eagles, alligators and other wildlife. They squelched in rubber boots through the mucky soil of cypress swamps, in search of species such as the Salyx willow tree, the original source of aspirin.
The group stayed in Quave’s hometown of Arcadia, in the home of her father, Raymond, who runs a business as a heavy equipment operator.
“We shopped at a produce stand and bought gorgeous avocados and flats of the freshest, local strawberries to take home and prepare,” Quave says.
Ko cited time spent preparing food as one of the trip highlights. “In my 18 years of life, I never learned to cook,” she wrote in her blog post. “When Dr. Quave watched me struggle even cutting a tomato, she taught me all I needed to know to make my portion of dinner: The guacamole. She taught me the importance of a healthy meal, which is something I never fully understood. During the trip, I was forced to opt for the healthier choices and loved almost every meal I ate.”
Exploring the Peace River by airboat, from left: Cassandra Quave, Jessie Cai, Adam Mackie, Rina Lee, Jennifer Ko and Justin Robeny.
Raymond Quave showed the students how to chop down a swamp cabbage palm and pull the heart of it, then taught them how to boil the heart for their dinner, seasoned with milk, bacon and salt and pepper.
“As an educator I see many extraordinarily bright and talented students who have few outdoor survival skills,” Quave says. “I want them to appreciate the importance of different plants, for the health and sustenance of humans as well as ecosystems.”
The students brought back more than 170 species to add to the Emory Herbarium, which they will also help preserve and annotate.
Capsella bursa-pastoris
“It was an amazing experience,” Mackie said of the Florida trip. “I had worked in the Herbarium and in Dr. Quave’s lab, but that isn’t the same as learning about plants in the field. Now I’m able to grind and preserve some of the dried plant materials that I collected myself.”
Quave, who serves as curator of the Herbarium, spearheaded efforts to reopen it in 2012, after decades of neglect. She recently launched a fundraising campaign to restore some of the specimens and keep the facility in operation (see box, above).
The Herbarium’s original collection manager, Madeline Burbanck, who researched the rare and endangered plants on Georgia granite outcrop ecosystems, played a pivotal role in the official designation of Arabia Mountain as a National Heritage Area.
Tharanga Samarakoon, a plant scientist from Sri Lanka, now serves as the Herbarium’s collections manager, overseeing student volunteers who are working at restoration and digitization efforts.
“The Herbarium is not just a musty room filled with dried plants,” Quave says. “It’s a window into the natural world and a valuable resource for research and education, across disciplines. We need to not only maintain natural habitats, but collect and preserve plant specimens over time, to better understand and monitor ecosystems.”
Globally, tobacco kills 5 million people each year, about 8.8 percent of all deaths.
