Many African-American patients refuse to join medical studies because they fear they will be lied to and harmed by scientists who view them as human guinea pigs, according to a study by Johns Hopkins researchers.
Confirming the observations of many researchers, the study might explain why clinical trials of new therapies fail to enroll enough black participants - and why trials might fail to predict how blacks will react to new drugs and medical devices.
Incidents such as the Tuskegee study - the infamous 40-year experiment in which researchers withheld treatment from black men with syphilis - have left many blacks wary of doctors and medical research, the Hopkins researchers concluded.
"African-Americans are twice as likely to perceive harm in clinical trials than whites," said Dr. Neil R. Powe, a professor of medicine at Johns Hopkins and lead author of the study, "and that accounts for their unwillingness to participate in medical research."
Other experts agreed that some African-Americans fear exploitation and urged researchers to allay those concerns by doing a better job of communicating the risks and benefits of medical research.
"While distrust is an issue, you have to ask yourself why is there still distrust," said Dr. Claudia R. Baquet, director of the University of Maryland's Center for Health Disparities. "One of the problems is physicians don't discuss clinical trials with their patients. People don't feel like they can make an informed decision about participating."
One recent study of 14 million cancer patients in the United States, for instance, found that while 3 percent to 4 percent of all patients participated in a clinical trial, only 0.5 percent of African-Americans patients participated.
Although researchers often cite distrust of the medical establishment as the reason blacks avoid studies, until now that opinion has been based mostly on anecdotal reports by doctors and researchers, Powe said.
"We thought we knew, but no one had made that direct link," he said.
To test whether African-Americans were indeed more fearful of medical research than whites, Powe and his colleagues surveyed 717 outpatients at 14 Maryland clinics. Of the respondents, 36 percent were black and the rest white.
When asked if they would participate in a mock study of a heart disease drug, black men and women were only 60 percent as likely as whites to agree to participate.
Blacks were also more distrustful of doctors than whites were. For instance, 58 percent of black patients felt their physicians would willingly give them experimental drugs without their consent, compared with 28 percent of whites.
Similarly, 25 percent of blacks but only 15 percent of whites said their doctors would ask them to participate in a risky study.
This distrust means that fewer blacks participate in research, Powe said, and as a result, studies might miss important biological differences in how people of different races respond to new medical therapies.
"If we don't test therapies in certain populations, how can we expect to know anything about whether they work in those populations?" Powe said. The results of his study were published online yesterday in the journal Medicine.
Wayne Bridge, 52, a retired African-American state trooper who lives in Baltimore, traced the origins of his general wariness to slavery. "After that little Carnival Cruise we enjoyed from Africa, maybe that plays a role in the attitude," he said.
Harriet A. Washington, the author of Medical Apartheid, a book published last year on the history of medical experimentation on African-Americans, said that the medical establishment's reputation for misleading blacks is deserved.
Among Washington's assertions: Sick black slaves in the 1800s were sold to doctors for experimentation, doctors sterilized blacks without their consent after the Civil War, and African-American patients were subjected to deadly, experimental doses of radiation in the 1950s.
"There is a long, unhappy and unfortunately consistent history of exploitation of blacks by the medical system," she said. "Many, many African-Americans have preserved the memory of these abuses."
Theodore Hunter, 60, an African-American resident of West Baltimore who works at Baltimore-Washington International Thurgood Marshall Airport, cited the Tuskegee study as a reason he would refuse to join a clinical trial. During the study, which ran from 1932 to 1972, white doctors allowed 400 black men, most of whom were illiterate, to suffer for decades without treatment.
Hunter sees Tuskegee as a cautionary tale. "We don't know what's going on at Johns Hopkins University or the University of Maryland," he said. "It might be run by white doctors, and you don't know if they're giving you something to make you better or worse."
Dr. Ezekiel Emanuel, the chair of the Department of Bioethics at the National Institutes of Health, acknowledged that racism existed - and might still exist - among doctors performing research.
But the exploitative research of the past, he said, was less directed at a certain race than at vulnerable populations in general - the poor, prisoners and institutionalized children, for instance.
"The question you have to ask is whether race was the determining factor - there were plenty of abuses of whites as well," he said. Researchers operate under much stricter ethical guidelines nowadays, he said, and clinical trials on the whole are safer.
"The practice of clinical research in the past was very different to what's been put in place now," he said. "It's usually in people's interest to participate now, but nothing is risk free."firstname.lastname@example.org email@example.com