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Science On Trial:  Medical Evidence And The Law In The Breast Implant Case

by Marcia Angell, M.D.

CLP Civil Justice Memo No. 28, August 1996

Marcia Angell, M.D. is executive editor of the New England Journal of Medicine and author of Science on Trial (W.W. Norton), a new examination of the history and causes of the silicone breast implant controversy.  Dr. Angell recently spoke about her book at a Manhattan Institute Forum in New York City.  Here are her comments. 

The breast implant scare is simply the most extreme of a number of similar alarms that have swept across the country over the last 20 years.  Others have centered on asbestos, DES, the morning sickness drug Bendectin, the Dalkon Shield contraceptive device, Agent Orange, and electromagnetic fields, to name just a few.  Some of these alleged hazards were real enough, others were greatly exaggerated, and still others were not hazards at all - or at least not shown to be.  What they all had in common was the marginal influence of science on the public alarm - and the thousands of lawsuits that ensued.  Why should science be so irrelevant in answering what are essentially scientific questions?  That's the text of my jeremiad.  I'll begin with a brief outline of how the breast implant scare developed.

Silicone gel-filled breast implants first came on the market in the early 1960s, but it wasn't until 1976 that they came under the purview of the FDA.  The FDA then had the option of asking the implant manufacturers for evidence of the implants' safety and effectiveness, but it didn't exercise that option for another 12 years.  After all, a lot of women had implants.  To be sure, they occasionally ruptured and caused other unpleasant local complications, but there was no evidence of systemic danger - that is, effects on the rest of the body.  Why not continue to grandfather them?

It wasn't until 1988 that the FDA finally announced that breast implant manufacturers would have to submit evidence of safety and effectiveness. And by law, they had to be given at least another 30 months to do so.

Why 1988, after implants had been on the market for nearly a quarter of a century, and a million or so women already had them?  There were several important developments during the 1980s that changed the FDA's relaxed attitude toward breast implants.  First, a number of anecdotes began appearing in the medical literature linking breast augmentation with systemic disease - most often cancer or connective tissue diseases.  Anecdotes are simply descriptions of isolated patients, so they can't speak to the issue of causation, although they can serve as a heads-up signal.  In this case, they did more than that.  Among other things, they put the subject on the legal radar screen.  The first multimillion dollar lawsuit alleging that silicone implants caused connective tissue disease was filed in 1982 in San Francisco, and it eventually resulted in a jury award of nearly two million dollars.  Not surprisingly, word traveled, and anecdotes in the medical literature multiplied, as women with implants who were sick or thought they might be sick sought medical attention.  Several more multimillion dollar verdicts followed. During the 1980s, then, there was a mounting - but still muffled - drumbeat of concern.

Perhaps the most important event to bring the growing unease about breast implants to widespread public attention was TV reporter Connie Chung's breathless treatment of the matter in 1990.  On her show, ``Face to Face with Connie Chung," she interviewed women who claimed to have autoimmune disease caused by their breast implants, and she made clear her view that implants were dangerous devices foisted off on unsuspecting women.  At about the same time, the late congressman Ted Weiss held public hearings, also marked by tacit acceptance of the view that breast implants were risky.  Advocacy groups were formed, and consumer groups, including Sidney Wolfe's Health Research Group, were mobilized.

In late 1991 and early 1992, all this activity finally came to a head.  First, FDA Commissioner David Kessler - newly arrived in Washington and a very different breed from earlier Commissioners - notified the manufacturers that their time was up.  They had just 90 days to produce evidence of the implants' safety.  The manufacturers - used to the relaxed treatment they had hitherto received from the FDA - hastily pulled together some numbers, but they by no means demonstrated safety.  Kessler then convened an advisory panel to consider the matter in public hearings.

Just about this time - by coincidence - a jury in San Francisco awarded 7.34 million dollars - the largest amount to date - to a woman who claimed that her breast implants, manufactured by Dow Corning, had caused her to develop mixed connective tissue disease.  In that trial, Dow Corning was accused of having known for years that implants were dangerous and suppressing the information.  The basis for this accusation was some internal documents the plaintiffs' lawyers had discovered at the Dow Corning plant.  When those documents were eventually released to the public, they did not show evidence of danger, but they did show that in the 1970s, the company had been more concerned with getting a new, softer implant on the market than with being sure it was safe.  Despite the lack of a smoking gun, the so-called ``secret documents" figured prominently in the FDA's deliberations.

On April 16, 1992, after impassioned public hearings before the advisory panel and in accord with the panel's recommendation, Kessler - under the glare of an intense public spotlight - banned the sale of silicone gel-filled implants.  They could be used only in clinical trials of breast reconstruction after cancer surgery.  The ban, Kessler was careful to point out, was not because implants had been found dangerous, but because the manufacturers had not proved them safe.

If Kessler thought the ban was the end of the matter, he was wrong.  Although he tried to reassure the million or so women who already had implants that there was no evidence of danger, the reassurances fell on deaf ears.  After all, why would the FDA take so drastic an action unless it knew there was substantial risk?  Many women with implants rushed back to their plastic surgeons to have the implants removed - and others rushed to court.

Almost overnight the trickle of lawsuits became a flood.  Dow Corning, for example, was the target of some 20,000 lawsuits filed in the first two years after the ban.  Most of the cases were settled out of court, but all it took were a few large jury verdicts to keep raising the stakes.  The largest verdict was for 25 million dollars - awarded in 1992 to a Houston woman, Pamela Johnson, who claimed that the silicone from a ruptured implant had caused a variety of nonspecific illnesses, such as recurrent respiratory and bladder infections.

Still, there was no good scientific evidence for or against a link between breast implants and systemic disease of any kind.  What we saw in the courtroom and in much of the media, at least at the time of the ban, were judgments based on anecdotes and speculation.  A small group of doctors and scientists were quick to concoct theories explaining how breast implants affected the immune system, without any evidence that they actually do.  Some of the theories were ingenious, some fanciful, none were proved.  Nevertheless, plaintiffs' attorneys made good use of the theoreticians as expert witnesses in court.  And the theoreticians made a good income being so used.  Plaintiffs' attorneys also made good use of a group of clinicians whose practice consisted largely of women with breast implants involved in litigation.  The doctors' fees were paid by the attorneys - and, not surprisingly, these doctors claimed to find implant-related illnesses in almost all the women referred to them.  They, too, made a good living.

Finally, in 1994, the breast implant manufacturers, desperate to limit their losses, agreed to the largest class action settlement in history.  According to its terms, 4.25 billion dollars would be set aside for all women with breast implants, of which one billion was earmarked for the lawyers.  The terms of the settlement were remarkably easy and generous.  Not surprisingly, nearly half of all women with breast implants registered for the settlement, and half of those claimed to be currently suffering from implant-related illnesses.  With so many women registered, not even 4.25 billion dollars could cover all the claims.  Dow Corning filed for bankruptcy protection, and the settlement collapsed a little over a year after it was crafted.  The remaining three large manufacturers - Baxter, Bristol-Myers Squibb, and 3M - agreed to another settlement with slightly more stringent terms and less generous compensation.  Whether this new agreement will hold together still remains to be seen.

After the ban, under the FDA's prodding, the breast implant manufacturers began to do what they should have done years earlier: they began to fund serious studies of the safety of breast implants.  Since about one percent of American women have breast implants and about one percent have connective tissue diseases, we could expect that by coincidence alone 10,000 women would have both (assuming roughly 100 million adult women in the United States).  The only way to show a link between implants and connective tissue disease, then, would be to show a higher prevalence of the disease among women with implants.  But doing so required good epidemiologic studies, and these had not been done at the time of the ban.

Now they've been done.  The first such study, from the Mayo Clinic, was published in the New England Journal of Medicine in June, 1994 - a full two years after the FDA ban and two months after the original global settlement was announced.  This study found no association between breast implants and twelve connective tissue diseases and a variety of signs and symptoms of such diseases.  Specifically, women with breast implants were no more likely to develop connective tissue disease than the age-matched controls without breast implants.  As the epidemiologists would say, the best estimate of the relative risk was one.  A few words of explanation:  The relative risk is obtained by dividing the incidence of disease in women with implants by the incidence in women without implants.  A relative risk of one means no difference.  Epidemiologic studies always yield estimates, not absolutes, since they deal with samples of a population, not the whole population.  The larger the sample studied, the more confident we can be that the estimate is correct - assuming a good study design - but we can never be absolutely certain.  Fortunately, the degree of uncertainty can be calculated.  In the Mayo Clinic study, for example, the relative risk was one, but there was a 95 percent probability that the true relative risk lay somewhere between 0.3 and 3.  Thus, although the best estimate was that the implants had no effect, there was still a small chance that they were associated with as much as a threefold increase in risk - or a decrease to a third the usual risk.

Since the publication of the Mayo Clinic study, several other epidemiologic studies have also failed to find a connection between breast implants and connective tissue disease or related signs and symptoms.  The most important of these was the Nurses' Health Study, published in the New England Journal of Medicine in June, 1995 - a year after the Mayo Clinic study.  In the Nurses' Health Study - which was larger than the Mayo Clinic study - the relative risk of connective tissue disease was 0.6.  Other studies have been published that focused on particular connective tissue diseases, including scleroderma, rheumatoid arthritis, and lupus.  These, too, failed to find an association with breast implants.

The only study to suggest a possible link was the Women's Health Cohort Study, published in the Journal of the American Medical Association in February.  It found that women with breast implants were 24 percent more likely to report having connective tissue disease - that is, a relative risk of 1.24.  Unfortunately, no attempt was made to verify the diagnoses.  Since the questionnaires were sent to the women after the FDA ban and all the publicity and legal activity, the findings could easily be explained by a reporting bias.  That is, women with implants would be more likely to claim a diagnosis of connective tissue disease.  The authors plan a follow-up study to verify the diagnoses.

Any future studies will certainly be plagued by the problem of reporting bias.  Even attempts to validate self-reports by medical records will be subject to bias, because there are now a number of doctors - as I mentioned - whose patients are referred to them by plaintiffs' attorneys and who diagnose implant-related illness so often that their records should be highly suspect.

In addition to the epidemiologic studies, there have been some laboratory studies looking at the effects of silicone on the immune system.  For the most part, these have been of poor quality.  They have focused on endpoints of uncertain significance and they have had inappropriate or inadequate control groups.

So what can we say now about the scientific evidence?  What we can say with reasonable confidence - on the basis of about ten epidemiologic studies done in the past four years - is that any link between breast implants and a variety of systemic diseases and symptoms is very small, if it exists at all.  Now it's true, as plaintiffs' attorneys are fond of pointing out, that the evidence doesn't eliminate the possibility of an effect.  But it does virtually eliminate the possibility of a large effect, and it gives no reason for believing there is even a small one.  The mere fact that a small risk could be missed does not mean that it was.

For an individual woman with implants wondering about her risk, even a doubling of risk would mean that her chances of developing connective tissue disease increased from one to only two percent (or, put another way, her chances of remaining free of connective tissue disease dropped from 99 percent to 98 percent) - not a large chance to take.  From a public health perspective, of course, a doubling of risk may matter, and it certainly would from the perspective of scientists interested in the causes of disease.  Unfortunately, these three different perspectives - individual, public health, and causal - are often blurred when we think about risks.  This confusion, in my view, is a frequent cause for the excessive alarm many individuals feel when they hear about small public health risks.

Now you might suppose that the accumulating scientific evidence would be reassuring.  But many women with implants have not been reassured, in part because of recent assertions that the diseases caused by breast implants are not the ``classical" connective tissue diseases, but rather a new syndrome, described so far only in vague and nonspecific terms.  Unfortunately, this assertion can't be either proved or disproved until the postulated syndrome is defined objectively enough to be studied.  It's impossible to study the prevalence of a clinical condition without diagnostic criteria.  And in the current climate, you would need objective criteria.

The recent emphasis on an elusive, undefined syndrome tells a lot about the debate.  It was only after evidence began to show little likelihood of a 1ink with cancer or connective tissue disease that attention shifted to a ``nonclassical" disease with largely subjective symptoms.  It was as though the proponents of implant-related illness were retreating from bunker to bunker as the evidence advanced.  Of course, it's possible that there is some unique syndrome not yet defined or studied, but that does not mean there is.

While the scientific evidence was accumulating to show little or no connection between breast implants and a number of systemic diseases, the courts were continuing in a quite different direction.  Late last year, for example, a jury in Reno, Nevada awarded 14.1 million dollars to a woman who sued Dow Chemical, the parent company of Dow Corning.  This case well exemplified the growing divergence between science and the law in the breast implant story.  The trial came after publication of the results of the Mayo Clinic study and the Nurses' Health Study, and these studies were cited by Dow Chemical in its defense.  Many observers thought that, unlike the earlier high-stakes cases, when there was little scientific evidence in either direction, this case, because of the preponderance of the evidence, would have to be decided in favor of the defendant.  But it wasn't.

Why is science in the courtroom so often disconnected from the scientific evidence?  The most important reason, in my view, is the way expert testimony is handled in the courtroom.  Witnesses are chosen by the adversaries' lawyers, paid by them, and rehearsed in advance.  Their credentials may be minimal or even irrelevant.  For example, pathologists may be permitted to testify about epidemiologic questions, for which they have no special competence or professional training.  Most important, witnesses are not required to cite evidence from the literature to buttress their opinions.  In the courtroom, the experts' opinions are the evidence.  This is a far cry from the scientific method, which accepts no conclusions, no matter whose they are, without evidence.

In my view, the best remedy for this situation would be for judges to exercise their option to call neutral witnesses for the court, and not to rely on witnesses called by the adversaries.  Fortunately, in the last couple of months, a few judges involved in breast implant litigation, including Judge Jack Weinstein here in New York, announced their intention to do exactly that.  I hope others will follow suit.

In addition to the incongruous way expert testimony is handled in the courtroom, there is another, more familiar reason for science to fare badly there.  Unlike other countries, the United States uses juries for tort cases involving highly technical matters.  This often leads to large sympathy verdicts for appealing plaintiffs who are taking on rich corporations, even when the verdict flies in the face of the evidence.

Since juries are drawn from the general public, the attitudes they bring with them to court reflect public opinion fairly faithfully.  Although I know of no systematic polls on the breast implant controversy, a large segment of the public seems to accept the view that breast implants cause serious disease, despite the lack of evidence.  I believe this mainly has to do with the post hoc, ergo propter hoc fallacy.  Many people simply can't accept the fact that if a woman falls ill after she gets implants, it may be coincidence.  Thus, the watchword of some women with implants, ``We are the evidence," seems reasonable to many people, although it's logically meaningless.  It's as though the rooster who crowed before dawn then took credit for the sunrise, and thought the sequence of events was proof enough.

The full effects of the breast implant controversy are far-reaching, and probably won't be entirely felt for years.  They certainly extend beyond the question of whether breast implants are safe - important though that question is.  Intensified concerns about groundless mass litigation threaten the whole medical device industry, as well as patients dependent on it.  Silicone is a component of a great variety of medical devices, some of them vital, including shunts, catheters, pacemakers, and artificial heart valves.  Already, mass litigation has been launched against manufacturers of penile implants and the Norplant contraceptive device, both of which contain silicone, and sales of Norplant have plummeted.  Probably the major threat is that suppliers of all raw materials - not just silicone - will no longer sell to manufacturers of medical devices.  According to American product liability law, suppliers can be held responsible for devices manufactured by other companies.  Most of the suppliers can well afford to pull out of this market, since it accounts for only a trivial part of their revenues, but the impact on patients may be tragic.

Of particular concern to the medical research community is the chilling effect of the legal dispute on the conduct of research studies.  No sooner had the major epidemiologic studies of breast implants been completed, when the institutions and investigators involved received subpoenas from plaintiffs' attorneys requesting much of their primary data - which in the large studies amounted to millions of documents.  The underlying, implied message was clear to the researchers and their institutions.  Research on breast implants could easily cost them vast amounts of time, energy, and legal fees, and also threaten the confidentiality of their important databases.  Why should they continue such research?

In my view, perhaps the most important aspect of the breast implant story is its reflection of what appears to be a widespread distrust and misunderstanding of science - and a corresponding embrace of pseudoscience.  In the long run, I believe, this growing alienation from science will cause more damage than any other aspect of the controversy.  Several jurors involved in breast implant cases, as well as the head of a powerful advocacy group, publicly stated that the results of scientific studies didn't matter to them.  In their view, medical research was not critical in settling the matter.

The breast implant controversy underscores our desperate need for a better public understanding of science, beginning with more and better science education in schools at all levels.  That means most of all attention to the way scientists think, including an understanding of the nature of evidence, the concepts of chance, probability and error, and the value of skepticism.  We also need better media reporting on scientific issues.  The best science reportage is very good, but in my opinion most stories about health risks fall far below that level.  When reporters writing about science have little or no training for their task and their editors seem more interested in entertaining or startling readers than in educating them, the public is not well served.

Modern history is replete with instances of fervent beliefs or conventional wisdom being proved wrong by scientific research.  Only a commitment to evidence can test the hopes, fears and biases that otherwise would have full sway.  Science is sometimes messy and slow, but it's the only method we have to answer questions about the material world and to evaluate the many health scares that recurrently sweep across the country.  Like democracy, it's better than whatever is second best, and we ignore it at our peril.