Association between advance directives and U.S. Medicare end-of-life expenditures varies across regions

Patients can use advance directives to document their preferences for the use or avoidance of life-sustaining treatments (living wills). "Although advance directives have become more common in the past few decades, evidence is mixed on whether they change the course of treatment provided near the end-of-life," according to background information in the article.

"The wide variation in end-of-life Medicare expenditures across geographic regions suggests that default treatment levels also vary regionally. Advance directives specifying limits at the end-of-life may have their greatest impact in regions where the norms are to provide very high-intensity end-of-life treatment."

Lauren Hersch Nicholas, Ph.D., M.P.P., of the University of Michigan, Ann Arbor, and colleagues conducted a study to analyze the relationship of advance directives for Medicare patients with the cost and aggressiveness of end-of-life treatment in geographic regions across the United States. The researchers collected survey data from the Health and Retirement Study for 3,302 Medicare beneficiaries who died between 1998 and 2007 linked to Medicare claims and the National Death Index. Various models examined associations between advance directives, end-of-life Medicare expenditures, and treatments by level of Medicare spending in the decedent's hospital referral region. The average age of the beneficiaries at death was 83 years; 56 percent were women. Regions were characterized by quartiles of end-of-life spending averaged across a 7-year period. Decedent's region intensity was determined by zip code of residence.

Among the findings of the researchers, decedents residing in low spending regions were more likely to have a treatment-limiting advance directive than decedents in high-spending regions (42 percent vs. 36 percent). In high-spending regions, adjusted spending on patients with a treatment-limiting advance directive was $33,933, whereas adjusted spending for patients without an advance directive was $39,518 (difference, -$5,585). Having a treatment-limiting advance directive was not associated with differences in aggregate end-of-life spending for decedents in low- and medium-spending regions.

In high-spending regions, patients without an advance directive had a 47 percent adjusted probability of in-hospital death, whereas those with an advance directive had a 38 percent probability of in-hospital death. "The equivalent results for in-hospital death for those in medium-spending regions were 42 percent without an advance directive and 37 percent with an advance directive. In high-spending regions, patients without a limiting advance directive had a 24 percent adjusted probability of hospice use, whereas those with a directive had an adjusted probability of hospice use of 41 percent," the authors write.

Advance directives were associated with higher adjusted probabilities of hospice use in high- and medium-spending regions, but not in low-spending regions.

"Advance directives are associated with important differences in treatment during the last 6 months of life for patients who live in areas of high medical expenditures but not in other regions. This suggests that the clinical effect of advance directives is critically dependent on the context in which a patient receives care. Advance directives may be especially important for ensuring treatment consistent with patients' preferences for those who prefer less aggressive treatment at the end of life but are patients in systems characterized by high intensity of treatment," the researchers conclude.

Editorial: The Evolution of Advance Directives

Douglas B. White, M.D., M.A.S., and Robert M. Arnold, M.D., of the University of Pittsburgh, comment on the use of advance directives in an accompanying editorial.

"With a healthy skepticism and a clearer understanding of the limitations of advance directives, clinicians, researchers, and policy makers are rethinking how broadly advance directives should be encouraged, how to overcome psychological biases that threaten the validity of advance directives, and how to incorporate advance directives into broader system-level interventions for end-of-life care. Most importantly, there is an ongoing reappraisal of whether the goal of advance care planning is to produce decisions in advance or, alternatively, to give family members and physicians the tools they need to make authentic treatment decisions for patients who lack decision-making capacity. As advance directives evolve, the difficult work continues."