Archives for the day of: December 5, 2011

From University of Michigan:

When people are under chronic stress, they tend to smoke, drink, use drugs and overeat to help cope with stress. These behaviors trigger a biological cascade that helps prevent depression, but they also contribute to a host of physical problems that eventually contribute to early death.

That is the claim of University of Michigan social scientist James S. Jackson and colleagues in an article published in the May 2010 issue of the American Journal of Public Health. The theory helps explain a long-time epidemiological puzzle: why African Americans have worse physical health than whites but better psychiatric health.

“People engage in bad habits for functional reasons, not because of weak character or ignorance,” says Jackson, director of the U-M Institute for Social Research. “Over the life course, coping strategies that are effective in ‘preserving’ the mental health of blacks may work in concert with social, economic and environmental inequalities to produce physical health disparities in middle age and later life.”

In an analysis of survey data, obtained from the same people at two points in time, Jackson and colleagues find evidence for their theory. The relationship between stressful life events and depression varies by the level of unhealthy behaviors. But the direction of that relationship is strikingly different for blacks and whites.

Controlling for the extent of stressful life events a person has experienced, unhealthy behaviors seem to protect against depression in African Americans but lead to higher levels of depression in whites.

“Many black Americans live in chronically precarious and difficult environments,” says Jackson. “These environments produce stressful living conditions, and often the most easily accessible options for addressing stress are various unhealthy behaviors. These behaviors may alleviate stress through the same mechanisms that are believed to contribute to some mental disorders—the hypothalamic-pituitary-adrenal cortical axis and related biological systems.”

Since negative health behaviors such as smoking, drinking alcohol, drug use and overeating (especially comfort foods) also have direct and debilitating effects on physical health, these behaviors—along with the difficult living conditions that give rise to them—contribute to the disparities in mortality and physical health problems between black and white populations.

These disparities in physical health and mortality are greatest at middle age and beyond, Jackson says. Why?

“At younger ages, blacks are able to employ a variety of strategies that, when combined with the more robust physical health of youth, effectively mask the cascade to the negative health effects,” Jackson said. “But as people get older, they tend to reduce stress more often by engaging in bad habits.”

Black women show heightened rates of obesity over the life course, he points out. In fact, by the time they are in their 40s, 60 percent of African American women are obese.

“How can it be that 60 percent of the population has a character flaw?” Jackson asks. “Overeating is an effective, early, well-learned response to chronic environmental stressors that only strengthens over the life course. In contrast, for a variety of social and cultural reasons, black American men’s coping choices are different.

“Early in life, they tend to be physically active and athletic, which produces the stress-lowering hormone dopamine. But in middle age, physical deterioration reduces the viability and effectiveness of this way of coping with stress, and black men turn in increasing numbers to unhealthy coping behaviors, showing increased rates of smoking, drinking and illicit drug use.”

Racial disparities in physical illnesses and mortality are not really a result of race at all, Jackson says. Instead, they are a result of how people live their lives, the composition of their lives. These disparities are not just a function of socioeconomic status, but of a wide range of conditions including the accretion of micro insults that people are exposed to over the years.

“You can’t really study physical health without looking at people’s mental health and really their whole lives,” he said. “The most effective way to address an important source of physical health disparities is to reduce environmentally produced stressors—both those related to race and those that are not. We need to improve living conditions, create good job opportunities, eliminate poverty and improve the quality of inner-city urban life.

“Paradoxically, the lack of attention to these conditions contributes to the use of unhealthy coping behaviors by people living in poor conditions. Although these unhealthy coping behaviors contribute to lower rates of mental disorder, over the life course they play a significant role in leading to higher rates of physical health problems and earlier mortality than is found in the general population.”

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From Pittsburgh City Paper, an outstanding article (the second in a series) touching on many of the themes behind Upstream

In October 1996, Lance Armstrong, then 25 and the world’s seventh-ranked professional bicyclist, learned he had testicular cancer. The cancer had spread to his lungs, brain and abdomen. He was given a 40 percent chance of survival.

“I intend to beat this disease,” he told reporters.

Armstrong survived, of course — the brain surgery, the grueling rounds of chemotherapy — and went on to seven straight Tour de France titles.

Armstrong’s recovery was received joyously. Headlines like “With Each Day, a Triumph” were standard; thousands of fan letters and emails arrived weekly. In 1999, Armstrong told Bicycling magazine, “The cancer — I owe my life to it. … I wouldn’t be married. I wouldn’t have a kid on the way. And I’m a [better] rider.”

News accounts noted everything from testicular cancer’s predilection for young men to survival tips from psychologists. But readers were rarely, if ever, informed that testicular cancer was becoming increasingly common. In the 20 years preceding Armstrong’s diagnosis, its incidence in the U.S. had risen by 41 percent. And it has kept rising: By 2007, testicular cancer was 75 percent more common than in 1975. And no one knows why.

Armstrong himself seemed disinterested in what causes testicular cancer. While his Lance Armstrong Foundation, created in 1997, has distributed countless yellow “Livestrong” wristbands, like most cancer initiatives it’s all about supporting cancer sufferers, not pursuing root causes.

Or, as Armstrong said shortly after his diagnosis: “I don’t want to waste my time saying, ‘Why me?’ I have a problem and I want to fix it.”

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It’s hard to believe we’d need to argue that preventing illness is preferable to trying to cure it. It’s as if we’d abandoned sewage-treatment systems because we have antibiotics for cholera.

And curing cancer is proving much harder than developing antibiotics.

Forty years into America’s “war on cancer,” you’re 50 percent more likely to get cancer than when it began. Childhood cancer rates have grown steadily for decades, according to National Cancer Institute statistics, and cancer is rising in people under 50. Yet the Institute’s own funding patterns emphasizes new treatments over prevention.

For instance, in 2010, the National Cancer Institute spent $364 million on prevention programs — and $1.16 billion on treatment research. (Asked about research priorities, an NCI spokesperson said “grants are awarded on a competitive basis” and research categories “[don’t] fully capture the complete range of research objectives” because some research applies in multiple categories.)

Treatment is likewise the focus of the vast majority of funds raised by your average “race for the cure” fundraiser.

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So why not put more effort into prevention?

It’s not a new question.

In his controversial 1979 book The Politics of Cancer, Samuel Epstein, a professor of environmental medicine, asserted that “cancer is caused mainly by exposure to chemicals or physical agents in the environment.” If those chemicals were removed, he argued, cancer would be “essentially preventable.” But he charged mainstream experts with downplaying the role of industrial carcinogens — and with pursuing lucrative treatments for cancer at the expense of prevention. Epstein cited ties between what he called “the cancer establishment” and the petrochemical and pharmaceutical industries; in the 1980s, for instance, the NCI Executive Cancer Panel was chaired by oil magnate Armand Hammer.

Epstein’s attacks were roundly criticized by the medical establishment. But little has changed, says epidemiologist Devra Davis, author of The Secret History of the War on Cancer.

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Popular culture too prefers “beating” cancer to sussing its source: For every movie about what carcinogens do, like Erin Brockovich, there are 10 Brian’s Songs or 50/50s, celebrating cancer’s noble victims or plucky survivors.

Public officials follow suit. When President Richard Nixon was pushing the National Cancer Act, in 1971, he issued a 1,300-word statement. While it briefly acknowledged evidence that “human cancers can be prevented by avoiding exposure to certain chemicals,” just 100 words of the statement concerned prevention. (Seven years after the surgeon general’s announcement that cigarettes cause cancer, Nixon’s statement didn’t even mention smoking.) Nixon’s repeated references to a “cancer cure,” meanwhile, signaled the chief goal.

Critics say those priorities are no accident. As difficult as curing cancer might be, it could be harder to reduce the malignant growth of special interests.

More scientists are now, like Epstein, raising alarms that synthetic chemicals drive cancer. Consider testicular cancer. Studies have linked exposure to hormone-mimicking chemicals (like those found in some pesticides and plastics) to reproductive abnormalities including undescended testicles, a cancer risk factor. Meanwhile, a 2008 study suggested that a byproduct of the pesticide DDT (still found in most Americans’ bloodstreams) increases the risk of testicular cancer.

And DDT is just one of at least 84,000 synthetic chemicals. Some are known carcinogens; the vast majority remain untested for health effects.

But passing laws to reduce exposure to such chemicals is difficult, partly because of the chemical industry’s political influence. According to opensecrets.org, the industry employs nearly 500 federal lobbyists and regularly spends $50 million a year on lobbying; top spenders this year include Dow Chemical, the American Chemistry Council and DuPont Co.

Epidemiologist Davis says she and other researchers who confront industry face threats to their funding or careers. Her Secret History of the War on Cancer documents the derailing of several researchers who explored tobacco or industrial pollutants. She cites, for instance, Wilhelm Hueper, whose pioneering research into industrial carcinogens got him fired by DuPont; he later worked for the National Cancer Institute, where industry pressure hamstrung his efforts until he left, in 1968.

When concerns about chemicals do arise, Davis observes, business interests take a page from the tobacco industry: They tout bought-and-paid-for studies showing their products are safe, and question the science behind the alarm bells.

Consider BPA, a plastics additive that’s caused cancer and reproductive problems in lab animals. For years, industry fought state-level bans on BPA in products like baby bottles and sippy cups; in 2009, the American Chemistry Council said that California’s effort would “needlessly restrict consumer products deemed to be safe by scientific experts worldwide.” In fact, there was some scientific concern about BPA, and a sign-off by the U.S. Food and Drug Administration was later revealed to have been heavily influenced by industry input. Then, just this past October, the ACC announced that manufacturers had quietly removed BPA from such products. “[T]hese products are not on the market. There is no need for parents or consumers to worry about them,” said an ACC spokesman.

Davis now runs the Washington, D.C.-based Environmental Health Trust. “Our motto is ‘Making Prevention the Cure,'” she says. “No matter how much money we spend on finding and treating cancer, no matter how good we get at treating it … if we don’t reduce the demand, we’ll never win.”

In the meantime, mystery chemicals continue to proliferate, at a clip not even Lance Armstrong could outrace.

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Image from Flickr.

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