Chapter 11. Emotions, Aggression, and Stress
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By NICHOLAS BAKALAR There is some evidence that stress prompts people to turn to sweet, high-calorie “comfort foods.” Now scientists have confirmed a link between long-term stress and obesity. The study, published in Obesity, tested 2,527 men and women over 50 years old, quantifying stress by measuring levels of cortisol, the stress hormone, in 2-centimeter hair clippings, or about two months’ growth. After controlling for age, sex, ethnicity, smoking, diabetes and other factors that might be linked to obesity, they found that the higher the level of cortisol, the greater the body weight, B.M.I. and waist circumference. Higher cortisol levels were also associated with persistence of obesity over time. Other studies have relied on measures of cortisol in blood, urine or saliva, which can vary by time of day and be affected by temporary stressors and other factors. But this study was able to measure general stress levels over two months to get a picture of the long-term effect. The researchers acknowledge that they were unable to determine whether chronically high cortisol levels are a cause or a consequence of obesity (feeling “fat,” for example, could raise your stress levels). The lead author, Sarah E. Jackson, an epidemiologist at University College London, said that while it may not be possible to eliminate stress, “you may be able to find ways to control it. Even just being aware that stress might make you eat more may help.” © 2017 The New York Times Company
By Daniel Engber It took scientists six months to train Alexandra the red-footed tortoise, but by midsummer 2009 she’d finally learned to fake a yawn. A formal experiment came right after. Once per day for several weeks, the research team placed Alexandra on one side of a small tank and another tortoise—either Moses, Aldous, Wilhemina, Quinn, Esme, or Molly—just across from her. They then signaled her to tilt back her head and drop her jaw, just as she’d been taught, while they watched the other tortoise. Would Moses drop his jaw? Would Aldous or Wilhemina? Was there any sign at all that Alexandra’s tortoise yawn could be contagious? There was not. The research team tried again, this time having Alexandra fake her yawn not just once but twice or three times over; still, the observer tortoises did not respond. Next the scientists made Moses and the others watch a video of Alexandra in the middle of a natural yawn, not the fake one that she’d been practicing for months. Again, the yawn was not contagious. “It is possible that a real yawn is necessary to stimulate the observer tortoise,” the authors concluded in their 2011 paper, published in Current Zoology. But “our findings are more consistent with the suggestion that tortoises do not yawn in a contagious manner.” This finding, or lack thereof, may on its surface seem banal. But given what we know about the replication crisis in science, the tortoise paper might be a sign of things to come. Is it possible that the entire body of research on contagious yawning—a small but lively field that dates back 30 years—is resting on a shaky premise?
Link ID: 23308 - Posted: 03.03.2017
By Veronique Greenwood A number of studies have used functional MRI to see what our brain looks like as we recall pleasant memories, watch scary movies or listen to sad music. Scientists have even had some success telling which of these stimuli a subject is experiencing by looking at his or her scans. But does this mean it is possible to tell what emotions we are experiencing in the absence of prompts, as we let our mind wander naturally? That is a difficult question to answer, in part because psychologists disagree about how emotions should be defined. Nevertheless, some scientists are trying to tackle it. In a study reported in the June 2016 issue of Cerebral Cortex, Heini Saarimäki of Aalto University in Finland and her colleagues observed volunteers in a brain scanner who were being prompted to recall memories they associated with words drawn from six emotional categories or to reflect on a movie clip selected to provoke certain emotions. The participants also completed a questionnaire about how closely linked different emotions were—rating, for instance, whether “anxiety” is closer to “fear” than to “happiness.” The researchers found that pattern-recognition software could detect which category of emotion a person had been prompted with. In addition, the more closely he or she linked words in the questionnaire, the more his or her brain scans for those emotions resembled one another. Another study, published in September 2016 in PLOS Biology by Kevin LaBar of Duke University and his colleagues, attempted to match brain scans of people lying idle in a scanner to seven predefined patterns associated with specific emotions provoked in an earlier study. The researchers found they could predict the subjects' self-reported emotions from the scans about 75 percent of the time. © 2017 Scientific American,
By Andy Coghlan People who have autoimmune disorders may be 20 per cent more likely to develop dementia. That’s according to an analysis of 1.8 million hospital cases in England. Based on data collected between 1999 and 2012, the study’s findings add to mounting evidence that chronic inflammation – a common feature of many autoimmune disorders – may be a trigger of dementia and Alzheimer’s disease. Previous studies have found that if infections or chronic inflammatory diseases – including diabetes – have pushed a person’s immune system into overdrive, this can lead to immune cells attacking healthy brain tissue. Varying effect According to the analysis, people with multiple sclerosis are among those with autoimmune disorders who are most likely to develop dementia. This finding isn’t very surprising, as the disorder is caused by the immune system attacking the central nervous system. The study, led by Michael Goldacre at the University of Oxford, found that people with the condition have double the risk of developing dementia. But other autoimmune disorders were also associated with rises in dementia risk. The skin condition psoriasis was linked to a 29 per cent increase, while the risk of developing dementia was 46 per cent higher in people who have lupus erythematosus, a disorder that involves rashes and fatigue. © Copyright Reed Business Information Ltd.
By Drake Baer If you’re going to get any sort of science done, an experiment needs a control group: the unaffected, possibly placebo-ed population that didn’t take part in whatever intervention it is you’re trying to study. Back in the earlier days of cognitive neuroscience, the control condition was intuitive enough: Just let the person in the brain scanner lie in repose, awake yet quiet, contemplating the tube they’re inside of. But in 1997, 2001, and beyond, studies kept coming out saying that it wasn’t much of a control at all. When the brain is “at rest,” it’s doing anything but resting. When you don’t give its human anything to do, brain areas related to processing emotions, recalling memory, and thinking about what’s to come become quietly active. These self-referential streams of thought are so pervasive that in a formative paper Marcus Raichle, a Washington University neurologist who helped found the field, declared it to be the “the default mode of brain function,” and the constellation of brain areas that carry it out are the default mode network, or DMN. Because when given nothing else to do, the brain defaults to thinking about the person it’s embedded in. Since then, the DMN has been implicated in everything from depression to creativity. People who daydream more tend to have a more active DMN; relatedly, dreaming itself appears to be an amplified version of mind-wandering. In Buddhist traditions, this chattering described by neuroscientists as the default mode is a dragon to be tamed, if not slain. Chögyam Trungpa, who was instrumental in bringing Tibetan Buddhism to the U.S., said the meditation practice is “necessary generally because our thinking pattern, our conceptualized way of conducting our life in the world, is either too manipulative, imposing itself upon the world, or else runs completely wild and uncontrolled,” he wrote in Cutting Through Spiritual Materialism. “Therefore, our meditation practice must begin with ego’s outermost layer, the discursive thoughts which continually run through our minds, our mental gossip.” © 2017, New York Media LLC.
Bruce Bower Chimps with little social status influence their comrades’ behavior to a surprising extent, a new study suggests. In groups of captive chimps, a method for snagging food from a box spread among many individuals who saw a low-ranking female peer demonstrate the technique, say primatologist Stuart Watson of the University of St. Andrews in Fife, Scotland, and colleagues. But in other groups where an alpha male introduced the same box-opening technique, relatively few chimps copied the behavior, the researchers report online February 7 in the American Journal of Primatology. “I suspect that even wild chimpanzees are motivated to copy obviously rewarding behaviors of low-ranking individuals, but the limited spread of rewarding behaviors demonstrated by alpha males was quite surprising,” Watson says. Previous research has found that chimps in captivity more often copy rewarding behaviors of dominant versus lower-ranking group mates. The researchers don’t understand why in this case the high-ranking individuals weren’t copied as much. The spread of new behaviors in groups of monkeys and apes depends on a variety of factors — including an innovator’s social status, age and sex — that can interact in unpredictable ways. “That’s why social learning in groups is so interesting to study,” says Elizabeth Lonsdorf, a primatologist at Franklin & Marshall College in Lancaster, Pa., who did not participate in the research. |© Society for Science & the Public 2000 - 2017.
By Michelle Roberts A multiple sclerosis treatment being tested in patients can stop the disease for at least five years, say doctors. The risky therapy involves wiping out the person's immune system with strong cancer drugs and then rebooting it with a stem cell transplant. Doctors say only some patients will be suitable to try it, particularly because it is so high risk. Out of 281 people who had the treatment, nearly half benefited, but eight died shortly afterwards. The work in JAMA Neurology is one of the largest and longest investigations of this aggressive MS treatment. Mark Rye, 41 and from Surrey, had his transplant just before Christmas 2016. Two months on he is doing well. "It was a hard decision, knowing what could go wrong. My wife and I discussed it for many, many hours. We've got small children and I didn't want my MS to get worse and end up in a wheelchair. "I did this to halt the condition and so that I can be there for my children, who are still so young. I want to be able to play rugby and football with them as they grow up." What is not clear is for how long the therapy might ultimately work. Freeze frame MS is not fatal, but it is incurable. The disease causes the immune system to attack the protective coating of nerves in the brain and spinal cord, which can create problems with a person's vision, walking and balance. © 2017 BBC
By Matthew Hutson, Veronique Greenwood For some things, such as deciding whether to take a new job or nab your opponent's rook in chess, you're better off thinking long and hard. For others, such as judging your interviewer's or opponent's emotional reactions, first instincts are best—or so traditional wisdom suggests. But new research finds that careful reflection actually makes us better at assessing others' feelings. The findings could improve how we deal with bosses, spouses, friends and, especially, strangers. We would have trouble getting through the day or even a conversation if we couldn't tell how other people were feeling. And yet this ability, called empathic accuracy, eludes introspection. “We don't think too hard about the exact processes we engage in when we do it,” says Christine Ma-Kellams, a psychologist at the University of La Verne in California, “and we don't necessarily know how accurate we are.” Recently Ma-Kellams and Jennifer Lerner of Harvard University conducted four studies, all published in 2016. In one experiment, participants imagined coaching an employee for a particular job. When told to help the employee get better at reading others' emotions, most people recommended thinking “in an intuitive and instinctive way” as opposed to “in an analytic and systematic way.” When told to make employees worse at the task, the participants recommended the opposite. And yet later experiments suggested this coaching was off base. For instance, in another experiment, professionals in an executive-education program took a “cognitive reflection test” to measure how much they relied on intuitive versus systematic thinking. The most reflective thinkers were most accurate at interpreting their partners' moods during mock interviews. Systematic thinkers also outperformed intuiters at guessing the emotions expressed in photographs of eyes. © 2017 Scientific American
By Nathaniel P. Morris Cardiovascular disease and mental illness are among the top contributors to death and disability in the United States. At first glance, these health conditions seem to lie at opposite ends of the medical spectrum: Treating the heart is often associated with lab draws, imaging and invasive procedures, whereas treating the mind conjures up notions of talk therapy and subjective checklists. Yet researchers are discovering some surprising ties between cardiac health and mental health. These connections have profound implications for patient care, and doctors are paying attention. Depression has become recognized as a major issue for people with heart disease. Studies have found that between 17 and 44 percent of patients with coronary artery disease also have major depression. According to the American Heart Association, people hospitalized for a heart attack are roughly three times as likely as the general population to experience depression. As many as 40 percent of patients undergoing coronary artery bypass surgery suffer from depression. Decades of research suggest these illnesses may actually cause one another. For example, patients with heart disease are often sick and under stressful circumstances, which can foster depressive symptoms. But depression itself is also a risk factor for developing heart disease. Researchers aren’t sure why, but something about being depressed — possibly a mix of factors including inflammatory changes and behavior changes — appears to increase risk of heart disease. © 1996-2017 The Washington Post
Emotions are a cognitive process that relies on “higher-order states” embedded in cortical (conscious) brain circuits; emotions are not innately programmed into subcortical (nonconscious) brain circuits, according to a potentially earth-shattering new paper by Joseph LeDoux and Richard Brown. The February 2017 paper, “A Higher-Order Theory of Emotional Consciousness,” was published online today ahead of print in the journal Proceedings of the National Academy of Sciences. This paper was written by neuroscience legend Joseph LeDoux of New York University and Richard Brown, professor of philosophy at the City University of New York's LaGuardia College. Joseph LeDoux has been working on the link between emotion, memory, and the brain since the 1990s. He's credited with putting the amygdala in the spotlight and making this previously esoteric subcortical brain region a household term. LeDoux founded the Emotional Brain Institute (EBI). He’s also a professor in the Departments of Psychiatry and Child and Adolescent Psychiatry at NYU Langone Medical Center. Why Is This New Report From LeDoux and Brown Significant? In the world of cognitive neuroscience, there's an ongoing debate about the interplay between emotional states of consciousness (or feelings) within cortical and subcortical brain regions. (Most experts believe that cortical brain regions house “thinking” neural circuits within the cerebral cortex. Subcortical brain regions are considered to be housed in “non-thinking” neural circuits beneath the 'thinking cap' of the cerebral cortex.) © 1991-2017 Sussex Publishers, LLC
Link ID: 23249 - Posted: 02.18.2017
Jon Hamilton Scientists may have solved the mystery of nodding syndrome, a rare form of epilepsy that has disabled thousands of children in East Africa. The syndrome seems to be caused by the immune system's response to a parasitic worm, an international team reports in the journal Science Translational Medicine. And they think it's the same worm responsible for river blindness, an eye infection that's also found in East Africa. The finding means that current efforts to eliminate river blindness should also reduce nodding syndrome, says Avi Nath, an author of the study and chief of the section of infections of the nervous system at the National Institute of Neurological Disorders and Stroke. "We can prevent new infections even if we can't treat the ones who already have nodding syndrome," Nath says. Drugs can kill the parasite in its early stages. Nodding syndrome usually strikes children between 5 and 16 who live in rural areas of northern Uganda and South Sudan. Their bodies and brains stop growing. And they experience frequent seizures. "These are kids, young kids, you would expect that they should be running around playing," says Nath, who visited Uganda several years ago. "Instead, if you go to these villages they are just sitting there in groups," so villagers can keep an eye on them. © 2017 npr
By Matt Blois A ruthless killer may soon help brain cancer patients. The rabies virus, which kills tens of thousands of people a year, has a rare ability to enter nerve cells and use them as a conduit to infect brain tissue. Now, scientists are trying to mimic this strategy to ferry tumor-killing nanoparticles into brain tumors. So far the approach has been shown to work only in mice. If successful in people, these nanoparticles could one day help doctors send treatment directly to tumors without harming healthy cells. The rabies virus, transmitted largely through the bites of infected animals, has evolved over thousands of years to hijack nerve cells, which it uses to climb from infected muscle tissue into the brain. That allows it to bypass a major hurdle: the blood-brain barrier, a selective membrane that keeps out most pathogens that travel through the bloodstream. But the barrier also prevents treatments—like cancer drugs—from reaching infected cells, limiting options for patients. To get around this problem, scientists are looking to the virus for inspiration. Already, researchers have packaged cancer-fighting drugs into nanoparticles coated with part of a rabies surface protein that lets the virus slip into the central nervous system. Now, a team of researchers from Sungkyunkwan University in Suwon, South Korea, has taken things one step further. Nanoparticle expert Yu Seok Youn and his team have engineered gold particles so that they have the same rodlike shape and size as the virus. The nanoparticle’s shape gives it more surface area than spherical particles, improving the surface protein’s ability to bind with receptors on nerve cells that serve as a gateway to the nervous system. The particles don’t carry any drugs, but the tiny gold rods readily absorb laser light, which heats them up and kills surrounding tissue. © 2017 American Association for the Advancement of Science.
Ian Sample Science editor Dozens of British children who developed narcolepsy as a result of a swine flu vaccine could be compensated after the high court rejected a government appeal to withhold payments. Six million people in Britain, and more across Europe, were given the Pandemrix vaccine made by GlaxoSmithKline during the 2009-10 swine flu pandemic, but the jab was withdrawn after doctors noticed a sharp rise in narcolepsy among those who received it. The sleep disorder is permanent and can cause people to fall asleep dozens of times a day. Some narcoleptics have night terrors and a muscular condition called cataplexy that can lead them to collapse on the spot. In 2015, a 12-year-old boy, known as John for the proceedings, was awarded £120,000 by a court that ruled he had been left severely disabled by narcolepsy caused by the vaccine. He was seven when he had the jab and developed symptoms within months. Because of his tiredness, John became disruptive at school and found it almost impossible to make friends. He takes several naps a day, cannot shower or take a bus on his own, and may never be allowed to drive a car. Despite paying out, the Department for Work and Pensions argued John’s disability was not serious enough to warrant compensation and said the court was wrong to take into account how the illness would affect him in the future. But the high court on Thursday rejected the government’s appeal that only the boy’s disability at the time should have been considered. The ruling paves the way for more than 60 other people to claim compensation. © 2017 Guardian News and Media Limited
Bruce Bower A small, poorly understood segment of the population stays mentally healthy from age 11 to 38, a new study of New Zealanders finds. Everyone else encounters either temporary or long-lasting mental disorders. Only 171 of 988 participants, or 17 percent, experienced no anxiety disorders, depression or other mental ailments from late childhood to middle age, researchers report in the February Journal of Abnormal Psychology. Of the rest, half experienced a transient mental disorder, typically just a single bout of depression, anxiety or substance abuse by middle age. “For many, an episode of mental disorder is like influenza, bronchitis, kidney stones, a broken bone or other highly prevalent conditions,” says study coauthor Jonathan Schaefer, a psychologist at Duke University. “Sufferers experience impaired functioning, many seek medical care, but most recover.” The remaining 408 individuals (41 percent) experienced one or more mental disorders that lasted several years or more. Their diagnoses included more severe conditions such as bipolar and psychotic disorders. Researchers analyzed data for individuals born between April 1972 and March 1973 in Dunedin, New Zealand. Each participant’s general health and behavior were assessed 13 times from birth to age 38. Eight mental health assessments occurred from age 11 to 38. |© Society for Science & the Public 2000 - 2016.
Link ID: 23200 - Posted: 02.08.2017
Aylin Woodward Fearful, flighty chickens raised for eating can hurt themselves while trying to avoid human handlers. But there may be a simple way to hatch calmer chicks: Shine light on the eggs for at least 12 hours a day. Researchers at the University of California, Davis bathed eggs daily in light for different time periods during their three-week incubation. When the chickens reached 3 to 6 weeks old, the scientists tested the birds’ fear responses. In one test, 120 chickens were randomly selected from the 1,006-bird sample and placed one by one in a box with a human “predator” sitting visibly nearby. The chickens incubated in light the longest — 12 hours — made an average of 179 distress calls in three minutes, compared with 211 from birds incubated in complete darkness, animal scientists Gregory Archer and Joy Mench report in January in Applied Animal Behaviour Science. Chickens exposed to lots of light as eggs “would sit in the closest part of the box to me and just chill out,” Archer says. The others spent their time trying to get away. How light has its effect is unclear. On commercial chicken farms, eggs typically sit in warm, dark incubation rooms. The researchers are now testing light's effects in large, commercial incubators. Using light exposure to raise less-fearful chickens could reduce broken bones during handling at processing plants, Archer says. It might also decrease harmful anxious behaviors, such as feather pecking of nearby chickens. G. S. Archer and J. A. Mench. Exposing avian embryos to light affects post-hatch anti-predator fear responses. Applied Animal Behaviour Science. Vol. 186, January 2017, p. 80. doi: 10.1016/j.applanim.2016.10.014. © Society for Science & the Public 2000 - 2016
By Emma Hiolski Imagine cells that can move through your brain, hunting down cancer and destroying it before they themselves disappear without a trace. Scientists have just achieved that in mice, creating personalized tumor-homing cells from adult skin cells that can shrink brain tumors to 2% to 5% of their original size. Although the strategy has yet to be fully tested in people, the new method could one day give doctors a quick way to develop a custom treatment for aggressive cancers like glioblastoma, which kills most human patients in 12–15 months. It only took 4 days to create the tumor-homing cells for the mice. Glioblastomas are nasty: They spread roots and tendrils of cancerous cells through the brain, making them impossible to remove surgically. They, and other cancers, also exude a chemical signal that attracts stem cells—specialized cells that can produce multiple cell types in the body. Scientists think stem cells might detect tumors as a wound that needs healing and migrate to help fix the damage. But that gives scientists a secret weapon—if they can harness stem cells’ natural ability to “home” toward tumor cells, the stem cells could be manipulated to deliver cancer-killing drugs precisely where they are needed. Other research has already exploited this method using neural stem cells—which give rise to neurons and other brain cells—to hunt down brain cancer in mice and deliver tumor-eradicating drugs. But few have tried this in people, in part because getting those neural stem cells is hard, says Shawn Hingtgen, a stem cell biologist at the University of North Carolina in Chapel Hill. © 2017 American Association for the Advancement of Science.
By Chelsea Whyte It was a gruesome scene. The body had severe wounds and was still bleeding despite having been lying for a few hours in the hot Senegalese savanna. The murder victim, a West African chimpanzee called Foudouko, had been beaten with rocks and sticks, stomped on and then cannibalised by his own community. This is one of just nine known cases where a group of chimpanzees has killed one of their own adult males, as opposed to killing a member of a neighbouring tribe. These intragroup killings are rare, but Michael Wilson at the University of Minnesota says they are a valuable insight into chimp behaviour such as male coalition building. “Why do these coalitions sometimes succeed, but not very often? It’s at the heart of this tension between conflict and cooperation, which is central to the lives of chimpanzees and even to our own,” he says. Chimps usually live in groups with more adult females than males, but in the group with the murder it was the other way round. “When you reverse that and have almost two males per every female — that really intensifies the competition for reproduction. That seems to be a key factor here,” says Wilson. Jill Pruetz at Iowa State University, who has been studying this group of chimpanzees in south-eastern Senegal since 2001, agrees. She suggests that human influence may have caused this skewed gender ratio that is likely to have been behind this attack. In Senegal, female chimpanzees are poached to provide infants for the pet trade. Fall from power Thirteen years ago, Foudouko reigned over one of the chimp clans at the Fongoli study site, part of the Fongoli Savanna Chimpanzee Project. As alpha male, he was “somewhat of a tyrant”, Pruetz says. © Copyright Reed Business Information Ltd.
By Simon Oxenham Ever felt hungry and angry at the same time? There’s evidence that “hanger” is a real phenomenon, one that can affect your work and relationships. The main reason we become more irritable when hungry is because our blood glucose level drops. This can make it difficult for us to concentrate, and more likely to snap at those around us. Low blood sugar also triggers the release of stress-related hormones like cortisol and adrenaline, as well as a chemical called neuropeptide Y, which has been found to make people behave more aggressively towards those around them. This can all have an alarming effect on how you feel about other people – even those you love. A classic study of married couples asked them to stick pins into “voodoo dolls” that represented their loved ones, to reflect how angry they felt towards them. The volunteers then competed against their spouse in a game, in which the winner could blast loud noise through the loser’s headphones. The researchers tracked the participants’ blood glucose levels throughout. They found that when people had lower sugar levels, the longer the blasts of unpleasant noise they subjected their spouse to, and the more pins they stuck into their dolls. But while being hungry really does change your behaviour, the effects of hanger have sometimes been overstated. One study that attracted attention a few years ago found that judges are less likely to set lenient sentences the closer it gets to lunch. © Copyright Reed Business Information Ltd.
Link ID: 23172 - Posted: 02.01.2017
By JAMES HAMBLIN In 1997, a few hundred people who responded to a job posting in a Pittsburgh newspaper agreed to let researchers spray their nostrils with a rhinovirus known to cause the common cold. The people would then be quarantined in hotel rooms for five days and monitored for symptoms. In return they’d get $800. “Hey, it’s a job,” some presumably said. Compensation may also have come from the knowledge that, as they sat alone piling up tissues, they were contributing to scientific understanding of our social-microbial ecosystem. The researchers wanted to investigate a seemingly basic question: Why do some people get more colds than others? To Gene Brody, a professor at the University of Georgia, the answer was “absolutely wild.” (Dr. Brody is a public-health researcher, so “wild” must be taken in that context.) He and colleagues recently analyzed the socio-economic backgrounds and personalities of the people in the Pittsburgh study and found that those who were “more diligent and tended to strive for success” were more likely than the others to get sick. To Dr. Brody, the implication was that something suffers in the immune systems of people who persevere in the face of adversity. Over the past two years, Dr. Brody and colleagues have amassed more evidence supporting this theory. In 2015, they found that white blood cells among strivers were prematurely aged relative to those of their peers. Ominous correlations have also been found in cardiovascular and metabolic health. In December, Dr. Brody and colleagues published a study in the journal Pediatrics that said that among black adolescents from disadvantaged backgrounds, “unrelenting determination to succeed” predicted an elevated risk of developing diabetes. The focus on black adolescents is significant. In much of this research, white Americans appeared somehow to be immune to the negative health effects that accompany relentless striving. As Dr. Brody put it when telling me about the Pittsburgh study, “We found this for black persons from disadvantaged backgrounds, but not white persons.” © 2017 The New York Times Company
By NICHOLAS BAKALAR Psychological distress may increase your chances of dying from cancer. Researchers interviewed 163,363 adults in England and Scotland using well-validated questionnaires on general and mental health. They followed the population in 16 studies conducted between 1994 and 2008. After controlling for age, smoking, physical activity and other factors, they found that compared with those with the lowest scores on depression and anxiety, those with the highest had higher rates of cancer death. The associations were particularly strong for colon and rectal, prostate, pancreatic and esophageal cancers, and for leukemia. In instances of colorectal and prostate cancer, they found a “dose-response” effect: the greater the distress, the greater the likelihood of death from those cancers. People might have had undiagnosed cancer at the start of the study, which would affect their mood, so the researchers accounted for this possibility by doing an analysis that excluded study members who died of cancer in the first five years. The results were largely the same. The study, in BMJ, is observational so cannot determine cause and effect, and it depended in part on self-reports. “The extent to which these associations could be causal,” the authors write, “requires further testing with alternative study designs.” © 2017 The New York Times Company