Posts filed under 'Tobacco Control'

Do “free markets” increase life expectancy disparities?

The New York Times today documents that the gap between rich and poor in the US involves not just income, but a growing disparity in life expectancy. Before people start complaining about Bush, not that the main data they present concerns the increase from 1980-1982, the beginning of the Reagan administration, to 1998-2000, the end of the Clinton administration. Presumably, Clinton’s free market ideology and policies contributed to the widening disparities.

Gap in Life Expectancy Widens for the Nation

by Robert Pear

New government research has found “large and growing” disparities in life expectancy for richer and poorer Americans, paralleling the growth of income inequality in the last two decades.

Life expectancy for the nation as a whole has increased, the researchers said, but affluent people have experienced greater gains, and this, in turn, has caused a widening gap.

One of the researchers, Gopal K. Singh, a demographer at the Department of Health and Human Services, said “the growing inequalities in life expectancy” mirrored trends in infant mortality and in death from heart disease and certain cancers.

The gaps have been increasing despite efforts by the federal government to reduce them. One of the top goals of “Healthy People 2010,” an official statement of national health objectives issued in 2000, is to “eliminate health disparities among different segments of the population,” including higher- and lower-income groups and people of different racial and ethnic background.

Dr. Singh said last week that federal officials had found “widening socioeconomic inequalities in life expectancy” at birth and at every age level.

He and another researcher, Mohammad Siahpush, a professor at the University of Nebraska Medical Center in Omaha, developed an index to measure social and economic conditions in every county, using census data on education, income, poverty, housing and other factors. Counties were then classified into 10 groups of equal population size.

In 1980-82, Dr. Singh said, people in the most affluent group could expect to live 2.8 years longer than people in the most deprived group (75.8 versus 73 years). By 1998-2000, the difference in life expectancy had increased to 4.5 years (79.2 versus 74.7 years), and it continues to grow, he said.

After 20 years, the lowest socioeconomic group lagged further behind the most affluent, Dr. Singh said, noting that “life expectancy was higher for the most affluent in 1980 than for the most deprived group in 2000.”

“If you look at the extremes in 2000,” Dr. Singh said, “men in the most deprived counties had 10 years’ shorter life expectancy than women in the most affluent counties (71.5 years versus 81.3 years).” The difference between poor black men and affluent white women was more than 14 years (66.9 years vs. 81.1 years).

The Democratic candidates for president, Senators Hillary Rodham Clinton of New York and Barack Obama of Illinois, have championed legislation to reduce such disparities, as have some Republicans, like Senator Thad Cochran of Mississippi.

Peter R. Orszag, director of the Congressional Budget Office, said: “We have heard a lot about growing income inequality. There has been much less attention paid to growing inequality in life expectancy, which is really quite dramatic.”

Life expectancy is the average number of years of life remaining for people who have attained a given age.

While researchers do not agree on an explanation for the widening gap, they have suggested many reasons, including these:

¶Doctors can detect and treat many forms of cancer and heart disease because of advances in medical science and technology. People who are affluent and better educated are more likely to take advantage of these discoveries.

¶Smoking has declined more rapidly among people with greater education and income.

¶Lower-income people are more likely to live in unsafe neighborhoods, to engage in risky or unhealthy behavior and to eat unhealthy food.

¶Lower-income people are less likely to have health insurance, so they are less likely to receive checkups, screenings, diagnostic tests, prescription drugs and other types of care.

Even among people who have insurance, many studies have documented racial disparities.

In a recent report, the Department of Veterans Affairs found that black patients “tend to receive less aggressive medical care than whites” at its hospitals and clinics, in part because doctors provide them with less information and see them as “less appropriate candidates” for some types of surgery.

Some health economists contend that the disparities between rich and poor inevitably widen as doctors make gains in treating the major causes of death.

Nancy Krieger, a professor at the Harvard School of Public Health, rejected that idea. Professor Krieger investigated changes in the rate of premature mortality (dying before the age of 65) and infant death from 1960 to 2002. She found that inequities shrank from 1966 to 1980, but then widened.

“The recent trend of growing disparities in health status is not inevitable,” she said. “From 1966 to 1980, socioeconomic disparities declined in tandem with a decline in mortality rates.”

The creation of Medicaid and Medicare, community health centers, the “war on poverty” and the Civil Rights Act of 1964 all probably contributed to the earlier narrowing of health disparities, Professor Krieger said.

Robert E. Moffit, director of the Center for Health Policy Studies at the conservative Heritage Foundation, said one reason for the growing disparities might be “a very significant gap in health literacy” - what people know about diet, exercise and healthy lifestyles. Middle-class and upper-income people have greater access to the huge amounts of health information on the Internet, Mr. Moffit said.

Thomas P. Miller, a health economist at the American Enterprise Institute, agreed.

“People with more education tend to have a longer time horizon,” Mr. Miller said. “They are more likely to look at the long-term consequences of their health behavior. They are more assertive in seeking out treatments and more likely to adhere to treatment advice from physicians.”

A recent study by Ellen R. Meara, a health economist at Harvard Medical School, found that in the 1980s and 1990s, “virtually all gains in life expectancy occurred among highly educated groups.”

Trends in smoking explain a large part of the widening gap, she said in an article this month in the journal Health Affairs.

Under federal law, officials must publish an annual report tracking health disparities. In the fifth annual report, issued this month, the Bush administration said, “Over all, disparities in quality and access for minority groups and poor populations have not been reduced” since the first report, in 2003.

The rate of new AIDS cases is still 10 times as high among blacks as among whites, it said, and the proportion of black children hospitalized for asthma is almost four times the rate for white children.

The Centers for Disease Control and Prevention reported last month that heart attack survivors with higher levels of education and income were much more likely to receive cardiac rehabilitation care, which lowers the risk of future heart problems. Likewise, it said, the odds of receiving tests for colon cancer increase with a person’s education and income.

1 comment March 23rd, 2008

Understanding research on cancer screening: Getting the numerator and denominator correct

Tuesday’s New York Times had a very nice story on lung cancer screening and how to reconcile two contrasting studies. One study showed that screening increased survival rates, while the other showed that screening did not reduce mortality (death rates). The paper is a nice example of the complexities involved incorrectly interpreting research.

How Two Studies on Cancer Screening Led to Two Results
By H. GILBERT WELCH, STEVEN WOLOSHIN and LISA M. SCHWARTZ

Of all the forms of cancer, lung cancer is by far the deadliest. So doctors have long hoped to come up with a screening test that would find it early, before it can grow and become untreatable.

Last fall, The New England Journal of Medicine published a study concluding that spiral CT screening (a kind of three-dimensional chest X-ray) would make most lung cancers curable. It sounded like wonderful news. For proponents of screening, it was a call to action: the Lung Cancer Alliance is starting an advertising campaign featuring sports celebrities trying to persuade you to make the “right call” and get screened.

But just last week The Journal of the American Medical Association published a study concluding that spiral CT screening is not only ineffective, but may actually be harmful, prompting unnecessary surgery that carries risks of its own.

How could these two studies — in the country’s two most prestigious medical journals — arrive at diametrically opposite conclusions? An answer requires a clear understanding of the goal of cancer screening.

That goal is to save lives — or, in scientific terms, reduce mortality. Simply finding cancer early is not enough.

Finding cancer early saves lives only if two conditions are met: the cancers detected are the ones that kill people; and early treatment prevents these deaths.

It is not enough to increase survival. While that may seem to be the mirror image of mortality, it can be a terribly misleading measure of the value of screening.

In the 1970s and ’80s, there was great interest in screening smokers for lung cancer using conventional chest X-rays. The question was seen as so important that it was examined using the gold standard of medical studies, a randomized trial. Half the participants were randomly selected to receive regular chest X-rays; half did not and served as the control group.

Three such randomized trials were conducted, and all three showed that screening did not reduce mortality. In fact, two reported slightly higher death rates in the group receiving chest X-rays.

The most famous of these trials, at the Mayo Clinic, showed how misleading survival can be. Although the 10-year survival rate doubled with screening, mortality was not reduced; indeed, screening may have increased it. The Mayo trial also showed that more than a decade after screening was stopped, there were still more cancers in the screened group. This shouldn’t happen: in two large randomly selected groups, there should be the same number of cancers in both. The chest X-rays must have detected some lung cancers that were never destined to cause symptoms or death — a phenomenon known as overdiagnosis.

This phenomenon challenges our conventional view of cancer as an inexorably progressive disease. Research in screening has demonstrated that what pathologists call cancer encompasses a broad spectrum of disorders: some cancers rapidly progress to death, some do so more slowly, and some don’t progress at all (or may even regress).

Overdiagnosis is even more of a concern for spiral CT, because it can detect far more abnormalities than chest X-rays. In fact, a screening program in Japan found about 10 times as many lung cancers with spiral CT as had been found in the same population using chest X-rays. More remarkably, the chance of having lung cancer detected by spiral CT was almost the same in nonsmokers and smokers.

This flies in the face of everything we know about lung cancer and smoking — 50 years of research showing that smokers are 10 to 20 times as likely as nonsmokers to die from lung cancer. This is powerful evidence that spiral CT detects some lung cancers that will never affect patients.

Because all lung cancer patients get treated, overdiagnosis means some people receive treatment that can’t help them (because they do not need it) and can only cause harm. Most patients given diagnoses of early lung cancer undergo surgery to remove part of a lung, a major operation from which about 5 percent die within a month.

With this background, let’s look at the two recent studies on screening.

The New England Journal study reported screening about 31,000 people with spiral CTs and finding 484 with lung cancer. These patients had a 10-year survival of 80 percent — compared with 10 percent for current lung cancer patients in the United States. The JAMA study reported screening about 3,200 people and finding 144 with lung cancer. (The detection rate was higher because this study had older patients and longer follow-up.) Of 3,200 people, 38 died from lung cancer — the same mortality rate expected for people of similar age and smoking history in the absence of screening.

In short, The New England Journal reported increased survival; JAMA reported no difference in mortality.

Most of us interpret “increased survival” to mean fewer deaths. But it does not, because survival is subject to two powerful distortions.

The first is called lead-time bias. Simply advancing the time of diagnosis (as with CT screening) will always increase survival.

Imagine two patients with lung cancer. Even if both die at age 70, a patient with cancer diagnosed by spiral CT screening at age 59 has a longer survival than one with cancer diagnosed because of symptoms (cough, weight loss and so on) at age 67. The first patient survives 11 years; the second 3 years. But both died at the same age. Survival is increased, but mortality is the same.

A second source of distortion results from overdiagnosis, when screening finds cancers that were never destined to progress and cause death. Overdiagnosis bias can also drastically inflate survival statistics, even if mortality is unchanged.

To understand why, you need to understand the definition of the two statistics. Both are fractions. Survival is calculated over a fixed period, for example 5 or 10 years.

Overdiagnosis inflates both the numerator of the survival statistic (number alive at a specified time) and the denominator (number of diagnoses). For the mortality statistic, overdiagnosis has no effect on the numerator (number of deaths) or the denominator (number studied). Perhaps the easiest way to understand this is to imagine if we told all the people in the country that they had lung cancer today: lung cancer mortality would be unchanged, but lung cancer survival would skyrocket.

The goal of lung cancer screening is to reduce mortality — to save lives. Because the New England Journal study examines only survival, it cannot tell us whether any lives are saved. Because the JAMA study examines mortality, it is the more valid study. It also corroborates the Mayo trial finding that a significantly increased survival rate can coexist with no difference in mortality.

The JAMA study also highlights the tradeoffs involved in lung cancer screening. The findings show that compared with no screening, if 1,000 people are screened over five years there would be 48 more lung cancer diagnoses, 46 more lung cancer operations (which would be expected to cause 2 deaths) and no lung cancer deaths prevented. The study data are consistent with as many as eight deaths prevented by screening, or eight extra deaths caused by it.

But neither study is definitive, because neither was a randomized trial. And both required assumptions. Given the potential benefit (so many people die from lung cancer) and the potential harms (some die from treatments), no one should have to assume anything.

Luckily, two randomized trials are under way — one a Dutch-Belgian collaboration, the other sponsored by the National Cancer Institute. Recent experience, notably with hormone replacement in postmenopausal women, has demonstrated how presuming benefits in the absence of randomized trials can cause real harm. To avoid repeating these mistakes, we should not screen for lung cancer unless the trials demonstrate a reduction in mortality.

This essay is by H. Gilbert Welch, Steven Woloshin and Lisa M. Schwartz. Dr. Welch is the author of “Should I Be Tested for Cancer? Maybe Not and Here’s Why” (University of California Press). He, Dr. Schwartz and Dr. Woloshin are senior research associates at the VA Outcomes Group in White River Junction, Vt.

1 comment March 15th, 2007

Are youth switching from cigarettes to cigars?

In preparation for an article, a reporter has asked for my comments on a recent letter in the American Journal of Public Health on the risks of young people switching from smoking cigarettes to smoking cigars. The letter cited data from the New Jersey Youth Tobacco Survey indicating that males had a higher rate of current cigar than of cigarette use. Further, they cited data from the 2003 National Survey on Drug Use & Health which indicate that youth and females constitute a large fraction of those initiating [starting use of] cigars.

I was asked to comment because I have done extensive research on youth use of alternative tobacco products, namely cigars, bidis [small hand-rolled cigarettes imported from India, and, in the US, often given kid-friendly flavors like “chocolate raspberry”] , and kreteks [tobacco cigarettes flavored with clove extract]. Those interested in reading my papers on this topic can find them on my publications page.

What follows are the reporters questions and my slightly edited replies:

1. What do you think of these study findings? Do they seem reasonable?

This study raises an important issue: whether declines in youth cigarette smoking are accompanied by an increase in alternative tobacco use, including most notably, use of cigars. I shared this concern when I did my work. As the authors point out, tax law currently facilitates this substitution process by making alternative tobacco cheaper than cigarettes.

As to whether this substitution is occurring, I don’t know. Examining the 2003 National Survey on Drug Use & Health: Results reference it isn’t as clear as the authors indicate. The authors refer to the following statement:

Initiation of cigar smoking more than doubled between 1990 and 1998, reaching a peak of 3.7 million new users in 1998. Between 2000 and 2002, cigar initiates declined from 3.6 million to 3.0 million. Since 1990, youths under 18 have constituted an increasingly greater proportion of the number of new cigar smokers, from 23 percent in 1990 to 46 percent in 2002. During that period, the proportion of cigar initiates that was female also increased, from 24 to 45 percent.

However, the same report states:

Current cigar use among the three age groups also was unchanged between 2002 and 2003. The rate was 4.5 percent in both years among youths aged 12 to 17; 11.4 percent in 2003 and 11.0 percent in 2002 among young adults aged 18 to 25; and 4.5 percent in 2003 and 4.6 percent in 2002 among adults aged 26 or older.

These prevalence rates are more in line with those usually seen in recent years in household surveys [school-based surveys, for methodological reasons, typically report higher rates for prevalence of most substances, making the two types of surveys not directly comparable.]. The higher initiation rates among youths under 18 are of concern and should be tracked. However, the overall prevalence rates do not suggest a mushrooming problem so far.

The rates reported in the letter for the New Jersey Youth Tobacco Survey are anomalous, as far as I am aware [I have not followed all the individual state prevalence reports.] In the 2004 National Youth Tobacco Survey they found:

In 2004, a total of 28.0% of high school students reported current use of any tobacco product (Table 2). Cigarettes (22.3%) were the most commonly used product, followed by cigars (12.8%), smokeless tobacco (6.0%), pipes (3.1%), bidis (2.6%), and kreteks (2.3%).

However, looking at the stats by gender in the New Jersey Youth Tobacco Survey Table 2, we see, for males: current cigarettes use — 22.1 (Confidence Interval 2.7); current cigar use — 18.4 (CI: 1.8) and A female cigar rate of 7.5 (CI: 1.4).

Thus, New Jersey has a much male lower cigarette use than nationally [great for them!], but little difference on cigars. This pattern is consistent with the authors’ argument in the letter. One would suspect that the cigarette tax there, perhaps accompanied by other tobacco control efforts, are responsible for the lower cigarette rate. So, efforts [taxes and other tobacco control efforts] may be necessary to reduce cigar use.

However, the authors don’t present their confidence intervals, a measure of the precision of their prevalence rates. It seems likely that the male cigarette and cigar rates are not in fact, significantly different. In other words, the higher rate for cigars is likely just a chance finding, not really higher. Of course, an equal rate for cigarettes and cigars could still be a serious problem.

In order to evaluate the New Jersey findings, we will need similar data from other states, or another year’s survey data from New Jersey.

2. Why is cigar use among teens a growing problem?

We don’t know. Originally, it was thought that the allure of cigars, a la, Cigar Aficionado magazine was the reason. My research suggested that this was a factor only among suburban kids.

An other factor [often ignored by tobacco control folks who don't think much about other types of substance abuse] include the fact that cigars are often hollowed out and used to smoke marijuana [called 'blunts']. Interestingly, I found that Philly’s blunts were the most frequently smoked cigar brand by kids, both when smoking cigars, and when making blunts.

Finally, there is the price factor, raised by these authors. They are perfectly correct that it makes no sense to tax alternative tobacco at lower rates than cigarettes are taxed.

3. In terms of danger to health, how do cigars compare to cigarettes?

Dangerous, but possibly somewhat less so. The National Cancer Institute, in their Cigar monograph: Cigars: Health Effects and Trends, found that cigars are associated with most diseases that cigarettes are, with the partial exception of lung diseases. The latter is because cigars are usually not inhaled.

However, there is some anecdotal evidence that some kids may inhale cigars. This was the issue I most regretted exploring in my own research on this. If kids inhale cigars, then cigars may be as, or even more dangerous than cigarettes, as cigars are less likely to be filtered.

A related issue that I have no data on is the relative addictiveness of nicotine as received from cigars as compared to cigarettes. The biggest reason tobacco use among teens is such a concern, is not the immediate health risks, but the fact that nicotine is highly addictive. Studies show that a fraction of teens start showing withdrawal symptoms within weeks of initiating smoking. Thus, youth tobacco use sets the young person up for a potential of many years of tobacco use, leading to the variety of chronic diseases.

Another issue we do not know the answer to is how much nicotine is absorbed when cigars are used as blunts to smoke marijuana. Is it enough to begin the addictive process? I wish we knew.

If cigars are as addictive as cigarettes, they would also hold the potential to create long-term smokers, whether of cigars or of other forms of tobacco. If youth inhale cigars, this likely would increase the addictive potential. There are a number of “ifs” here, but we should be finding out.

4. Do you think public health folks are doing enough about the cigar problem? What more could be done?

No. There has been very little attention to cigars among public health folks. When I conducted my study, it was virtually the first study focused on alternative tobacco use. Many health educators and others were completely unaware of issues around alternative tobacco use. This needs to change. I think it is starting to change, but more needs to be done. I also think we need to learn more about effective tobacco control strategies for reducing cigar use.

5. Might there be any benefit to teens smoking cigars instead of cigarettes? (i.e., less exposure to tobacco, they’re less socially acceptable in some parts, etc.)

As to the exposure to tobacco, see my comments above. We simply don’t know enough about how kids use cigars to know if they’re getting less nicotine. Same about the relative social acceptability and its effects. On the other hand, young people are often attracted to substances because they are “forbidden”. We don’t know enough to know how these relative factors work out.

1 comment November 23rd, 2005


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