Background: Living wills are considered clear and convincing evidence of a person's preferences for end-of-life treatment. Unfortunately, living wills often use vague language that forces physicians and others to infer specific treatment choices, like the choice to forgo cardiopulmonary resuscitation (CPR). To test the validity of such inferences we examined the relationship between living will completion and CPR preference. We also examined whether CPR choices were fixed or could be influenced by detailed information on CPR.
Methods: We interviewed 102 retired elderly persons, many of whom had living wills. We obtained CPR preferences in five hypothetical scenarios before and after providing CPR information. We then analyzed differences in desire for CPR between the group of subjects with living wills and the group without.
Results: In each scenario there were subjects in both groups who desired CPR. The group with living wills desired less CPR in scenarios involving functional impairment and cognitive impairment, but not in scenarios involving current health, severe illness, and terminal illness. After receiving CPR information, both groups changed their preferences such that intergroup differences were no longer seen.
Conclusions: Preferences for CPR among subjects with living wills are not homogeneous, but distributed across the clinical scenarios. Therefore, one cannot infer CPR preference from the mere presence of a living will. Cardiopulmonary resuscitation information can influence preferences even among persons with living wills, implying that preferences are neither fixed nor always based on adequate information. Physicians should view vaguely worded documents as unreliable expressions of treatment preference that should not supplant informed discussion.