Checklist Predicts if You'll Be Alive in 10 Years
People with a total score of one have, on average, a 5 percent chance of dying in the next 10 years. A score of five translates to a 23 percent chance of dying within a decade, while a score of 10 corresponds to a 70 percent risk.
None of that is set in stone, Cruz said, but the scoring system breaks people into "rough categories" of risk.
Having an idea of an older patient's life expectancy is important because some medical interventions "take a long time to pay off," said Dr. James Pacala, president of the American Geriatrics Society.
"Most cancer screenings, for example, take five to 10 years to pay off," Pacala said. For an older person unlikely to live that long, the risks of screening -- such as false-positive results, needless invasive tests and anxiety -- are likely to outweigh any benefit.
"If you care for older patients, this is something you always have running in the back of your mind," Pacala said. "What is the rest of this patient's life likely to look like?"
Right now, he said, doctors can get an idea by looking up average life expectancy for a patient based on age and sex, and then considering that person's overall health. The checklist in this study, Pacala said, offers a more "formal" way to do that.
"This provides us with evidence-based numbers," he said.
Pacala stressed, however, that decisions on whether to screen for or treat a disease should not be based solely on a number. He said longevity estimates should be used to facilitate discussions between doctors and patients.
A doctor not involved in the study agreed.
"There is absolutely a need for better tools for understanding life expectancy," said Dr. Ethan Basch, an oncologist and director of the cancer outcomes research program at the University of North Carolina School of Medicine, in Chapel Hill.
But no life-expectancy calculator -- or any single guideline -- is enough, Basch said. "This is one piece of information to help an older patient make an informed, rational decision," he said.
Basch chaired the American Society of Clinical Oncology committee that recently developed the group's guideline on PSA screening for prostate cancer. The society suggests that doctors discuss PSA screening with men who are expected to live for more than 10 years.
PSA screening is controversial because prostate cancer is often slow-growing and will never threaten a man's life. Even if screening catches a prostate tumor, many men may be treated unnecessarily.
For a man expected to live fewer than 10 years, the ASCO says the potential harms of PSA screening seem to outweigh the benefits. For men with a longer life expectancy, the group says things are not so clear-cut, and having a conversation with your doctor might be worthwhile.