According to new research from the University of Michigan and the Veterans Affairs Ann Arbor Healthcare System, a record number of elderly people are completing living wills to guide end-of-life medical treatments - up from 47 percent in 2000 to 72 percent in 2010.

However, even with nearly double the number of people completing advance directives - which may specify preferences for surrogate decision makers and life-support treatment - there was little difference in hospitalization rates or deaths in the hospital, says the study that appears in the Journal of the American Geriatrics Society.

"Given the aging population, there's been a great push to encourage more people to complete advance directives with the idea that this may increase hospice care and reduce hospitalization for patients during the last six months of life," says lead author and palliative care specialist Maria Silveira, M.D., M.A., M.P.H, researcher with the VA Ann Arbor Healthcare System and assistant professor in the Department of Internal Medicine at the U-M Medical School.

"We found that while there's an upward trend in creating these documents, it didn't have much bearing at all on hospitalization rates over the decade. Indeed, hospitalization rates increased during the decade, rather than go down. These are really devices that ensure people's preferences get respected, not devices that can control whether a person chooses to be hospitalized before death."

Silveira says the increase in advanced directives indicates that people are less timid about broaching end-of-life planning and talking about death with loved ones.

"People seem more comfortable having 'the talk' about those dire "what-if" scenarios and death in general," says Silveira, who is also a member of the Institute for Healthcare Policy and Innovation. "It's become part of the routine check list in getting affairs in order, especially for older adults. People want to ease the burden upon their loved ones who will undoubtedly face difficult decisions when it comes to handling finances, medical treatment and other matters."

The study was based on data from the Health and Retirement Study, a nationally-representative sample of older Americans that is conducted by the U-M Institute for Social Research on behalf of the National Institute of Aging.

Recent headlines have shone a light on end-of-life treatment choices around the country. Among the most highly publicized cases was that of a brain-dead pregnant woman in Texas who was kept on life support because of confusion over state law. A judge ultimately ordered the Texas hospital to take the woman off of her ventilator in January to honor her family's wishes.

The recent study found that most people both appointed a surrogate and left their treatment preferences known. Among those who only had completed one document, more chose to appoint a surrogate than leave their treatment preferences in writing.

"Identifying the person you trust to make these types of medical decisions isn't as emotional a decision as deciding whether you'd want aggressive treatment or hospice care if you're dying," Silveira says. "It's much more difficult to make decisions about treatment because it often depends on unforeseeable factors such as how sick the person is, whether his or her brain is working and chances of recovery."

Silveira says that some insurers and stakeholders have encouraged primary care physicians to talk to healthy patients about whether they have completed a will, but the new findings suggest that the documents likely don't change the likelihood of hospitalization at the end of life or increase the likelihood the person will die at home.

Some people may also opt against a living will for cultural reasons, Silveira noted. For patients who believe families should make these decisions as a group, on their behalf, an advance directive may not be the correct way to prepare for the end of life, she says.

"As a physician, when you help a patient prepare for the end of life, it depends on the patient's age, their medical conditions, and their lifestyle," Silveira says. "As a family, it can never be too early to talk about these issues."