The "vulnerable groups" included elderly people, poor, women, minorities, uninsured, minors, chronically ill, less educated or psychiatric patients and AIDS patients. Out of these vulnerable groups, only AIDS patients used doctor-assisted suicide at elevated rates.
Led by bioethicist Margaret Battin, a University of Utah distinguished professor of philosophy and adjunct professor of internal medicine, the research deals with the so-called "slippery slope" argument that has been made by critics of doctor-assisted suicide and has raised concern even among proponents.
The argument is that by making it legal for medical doctors to help certain patients end their lives, vulnerable people will die in disproportionately large numbers.
"Fears about the impact on vulnerable people have dominated debate about physician-assisted suicide. We find no evidence to support those fears where this practice already is legal," Battin said.
The study will be published in the October 2007 issue of the Journal of Medical Ethics.
The findings of the research came through when Battin and her colleagues looked at the places where physician-assisted suicide is legal.
The researchers analysed data on assisted suicide and voluntary active euthanasia in the Netherlands by taking data from four government studies and several smaller ones. They analysed Oregon Department of Human Services annual reports, and surveys of physicians and hospice professionals.
Battin's team looked at Oregon, which is the only U.S. state where physician-assisted dying is legal. In the first nine years after the law took effect in the state, 456 patients received lethal prescriptions and 292 of those actually used the drugs to kill themselves. That is 0.15 percent of all deaths in Oregon during the same period.
They also looked at the Netherlands and found that of 136,000 deaths annually in the Netherlands, about 1.7 percent are by voluntary active euthanasia, 0.1 percent by physician-assisted suicide and 0.4 percent are "extralegal" because they involve patients with no current explicit request to die, but who either made one before becoming incompetent or are perceived to be suffering intolerably.
The results of the data analysed fell into three categories:
· Elderly people, women and uninsured people do not die in disproportionate numbers where physician-assisted death is legal, but AIDS patients do. (The insurance data is from Oregon only; everyone is insured in the Netherlands.)
· Physician-assisted death does not kill disproportionate numbers of people who are poor, uneducated, racial and ethnic minorities, minors, or people with chronic physical or mental disabilities or chronic but not terminal illnesses.
· People with psychiatric illness - including depression and Alzheimer's disease - are not likely to die in lopsided numbers.
Therefore the researchers concluded, "Those who received physician-assisted dying ... appeared to enjoy comparative social, economic, educational, professional and other privilege".
They also observed that in both Oregon and the Netherlands, people who received a doctor's help in dying averaged 70 years old, and 80 percent were cancer patients.
In case of AIDS patients, during nine years of the Oregon Death with Dignity Act, only six patients with the disease died with physician assistance - 2 percent of all deaths under the law. Yet, the researchers write, "Persons with AIDS were 30 times more likely to use assisted dying" than a comparable group of non-AIDS patients who died of chronic respiratory disorders.
In a group of 131 homosexual men in Amsterdam who were diagnosed with AIDS, 22 percent died via physician-assisted suicide or euthanasia. The rate may be lower now since the advent of medicines that make it possible for many patients to live with AIDS as a long-term chronic illness.
Battin said: "We've known for a long time from studies elsewhere that rates of assisted dying were much higher in people with AIDS," particularly in areas with large, supportive gay communities such as San Francisco.
It's not a surprise to find high rates where physician-assisted dying is legal".