There is no way to predict exactly how long any of us is going to live, except perhaps those who are so ill that their organs are shutting down. Of course, demographers working for the government and insurance companies need to estimate life expectancy of various populations to plan budgets and benefits.
When I was in medical practice, I had many conversations with patients about life expectancy. Often, these discussions were uncomfortable. But they were important. An accurate estimate can help withmaking medical decisions at older ages. For instance, various guidelines wisely advise that people with a predicted life expectancy of less than 5 or 10 years should stop being screened for cancer, since it’s likely they won’t live long enough to reap the benefits but may experience short-term harms. Knowing they have a relatively short life expectancy can also lead individuals to decide not to have aggressive treatments. On the other hand, if you mistakenly think you won’t live many more years, you might choose to forgo testing and treatments that may still help you.
But many people do not want to discuss such matters, according to a study in the Annals of Family Medicine in December 2018, in which 878 adults (average age 73) received a description of a hypothetical patient who had limited life expectancy but whose death was not imminent. They were asked, if they were the patient, would they want to know their life expectancy. About 60 percent did not want to know. Of these, 6 out of 10 thought the doctor should not even offer the discussion; 9 out of 10 did not want the doctor to discuss their limited life expectancy with family or friends. More participants said they would be willing to discuss life expectancy if it were less than two years.
Factors associated with increased willingness to discuss life expectancy included higher educational level, belief that doctors are good at predicting life expectancy, and past experiences with either a life-threatening illness or with discussing life expectancy of a loved one.
In another study, published in 2017 in JAMA Internal Medicine, 40 people (average age 76) were surveyed about stopping cancer screening when life expectancy is limited; half had an estimated life expectancy of less than 10 years. While most were amenable to the idea of stopping because of advanced age and poor health status, especially if they had a trusting relationship with their doctor, almost all objected to a guideline explicitly recommending against screening those with limited life expectancy. Specific wording about life expectancy was important: Many felt language such as “you may not live long enough to benefit from this test” was unnecessarily harsh compared with the more neutral message that “this test would not help you live longer.”
Studies have shown that people are not good at estimating how long they are likely to live based on their age and health. Health care providers may not be much better at predicting patients’ life expectancy and may be inadequately trained to discuss it. Fortunately, there now are online tools that help doctors estimate prognosis and likely survival rates, evaluate the advisability of continued cancer screening, and even offer guidance about how best to communicate such information. One such tool is ePrognosis from UC San Francisco.
Bottom line: Discussing their life expectancy and other matters having to do with death can be difficult for patients as well as for their doctors. The key to such conversations is trust. No one has a crystal ball, and there will always be people who beat the odds. But if you are older and facing major medical decisions, you may want to bring up this subject with your doctor. Patients should always be given a choice about hearing numerical predictions about their future, even if they have a life-threatening disease.
This article first appeared in the UC Berkeley Wellness Letter.