Illness, aging may not change end-of-life choices

By Anne Harding

NEW YORK (Reuters Health) - People who say they wouldn't want life-sustaining treatments if they were brain dead tend not to change their minds over time, but the preferences of those who want more aggressive treatment are less stable, a new study of aging doctors suggests.

Dr. Marsha N. Wittink of the University of Pennsylvania School of Medicine in Philadelphia and her colleagues also found that aging or changes in study participants' mental and physical health had little influence on their treatment preferences.

But the doctors who didn't have advance directives were more likely to change their minds. Advance directives are documented instructions on a person's preferences for medical care if they lose the ability to make such choices for themselves.

"That suggests to us that there's something very deliberate about going through that process" of creating an advance directive, Wittink told Reuters Health. "What the average person might want to take from this is that the process of sitting down with your family and loved ones and physician is an important one."

To gauge the stability of preferences in end-of-life care, the investigators used data from the Johns Hopkins Precursors Study, one of the longest-running studies of aging in the world. It is open to everyone who graduated from the university's School of Medicine from 1948 to 1964, and was designed to examine risk factors for premature heart disease and death.

Wittink and her colleagues looked at 1999 and 2003 survey results for 818 of the study's participants, who were asked whether or not they would want 10 different types of life-sustaining treatment if they had suffered permanent brain damage and were no longer able to speak or recognize people. The researchers grouped them into three categories based on the aggressiveness of their treatment preferences.

In 1999, 62 percent of the study participants fell into the "least aggressive" category, 26 percent opted for intermediate care, and 12 percent opted for the "most aggressive" care.

Three years later, the breakdown was virtually identical, but 60 percent chose the least aggressive care and 14 percent chose the most aggressive.

Eighty percent of the physicians who initially chose the least aggressive care made the same choice three years later. But just 41 percent of those who had first said they preferred the most aggressive care still did at the second survey.

A person's mental or physical health didn't have much influence on whether or not they changed their preferences. But the doctors who did not have advance directives were twice as likely to change their preferences as those who did.

Physicians have a clear understanding of what's involved in life-sustaining treatments such as mechanical ventilation, intravenous fluids, and tube feeding, Wittink noted in an interview, so their end of life preferences may be more stable than those of people in the general population, who have less information on these treatments.

SOURCE: Archives of Internal Medicine, October 27, 2008.