Advance directives work. That's the conclusion of one of the largest studies on the effectiveness of documents specifying what medical treatments are desired, or not desired, at the end of life. Further, Americans are increasingly making use of the tool.
In a study of 3,746 deaths, researchers found that 42.5% of patients had faced treatment decisions near the end of their lives but that more than 70% of those people had lacked the ability to make choices because of their mental or physical health. Among that group, however, the majority -- 67.6% -- had advance directives.
Moreover, the instructions left in the advance directives were almost always carried out by surrogate decision-makers. The will of the patient, said the lead author of the study, prevailed.
"This is a big change from the early '90s, when studies reported that only about 20% of people had advance directives," said Dr. Maria J. Silveira, a clinical scientist at the Veterans Affairs Ann Arbor Healthcare System and an assistant professor at the University of Michigan. "I think it shows the public has bought into this and thinks it's important."
The study, published in the New England Journal of Medicine, is among the first to look at how well advance directives work. Most common among such documents are living wills and durable powers of attorney. The former specifies the types of medical treatment desired should an individual become incapacitated; the second gives someone else the legal authority to make decisions for the patient.
Silveira used data from the long-running Health and Retirement Study, which surveys adults ages 51 and older nationwide. In analyzing data from people ages 60 and older who died between 2000 and 2006, researchers found that of the 398 incapacitated people who had used a living will to request limited care at the end of life, almost 83% received it. Limited care was described as care in only certain situations.
Of the 417 incapacitated people who had requested comfort care in a living will, 97% received it. Comfort care was described as being kept comfortable and pain-free while forgoing extensive measures to prolong life.
It's unlikely, however, that the study's findings broadly apply to all communities, said Dr. Pamelyn Close, director of adult and pediatric palliative care at Los Angeles County-USC Medical Center.
"No one population is ever going to be predictive," said Close, who was not involved in the study. "Whenever you have a large ethnic and demographic mix, it will be different. Very few of our patients here come in with advance directives."
The only area cited in the study in which advance directives were not as effective was when patients requested aggressive care. Then, only half -- five of the 10 people who requested it -- received it. Silveira said, in many cases, aggressive care was simply not an option.
"People have a lot of expectations that these documents will be perfect to foresee and prepare us for every situation that could arise," Silveira said. "For those of us who do this on a regular basis, we accept that this is the best we've got. And they do very well."
Although only 10 people among the thousands studied requested aggressive end-of-life care in an advance directive, that situation is especially sensitive to some Americans. During the recent debate over healthcare reform, some lawmakers suggested that legislation might include so-called death panels that would decide a dying person's fate with no regard for the patient's preferences.
An editorial accompanying the study says that other researchers have found advance directives to be of limited value. "What we really would like to know -- whether the preferences of patients were any more likely to be honored if they had a living will than if they did not -- cannot be determined from this study," said the author of the commentary, Dr. Muriel R. Gillick, a specialist in end-of-life care at Harvard Medical School's Department of Population Medicine.