Objective: Would increasing the documentation of advance directives (ADs) lead to a reduction in resource utilization? We examined this question by conducting three secondary analyses: (1) we tested for a change in resource use among those who died in the hospital at a time before and after an intervention that increased the documentation of ADs in the medical record; (2) we replicated analyses of published studies that reported an association of chart documentation of ADs and hospital resource use; and (3) we examined whether a potential explanation of the observed association is biased documentation of ADs among patients who have completed an AD.
Design: Replication of analysis of previous published studies using data from a prospective cohort study and block-randomized controlled trial.
Setting: Five teaching hospitals in the United States.
Patients: A total of 9105 seriously ill patients were enrolled in the Study to Understand Prognoses and Preferences for Outcomes and Risks of Treatments (SUPPORT), including 4301 patients in the 2 years (1989-91) before the Patient Self-Determination Act (PSDA) and 4804 in the 2 years (1992-94) after the PSDA implementation, with 2652 patients receiving the intervention and 2152 serving as controls.
Interventions: The SUPPORT intervention provided a nurse to facilitate communication among patients, surrogates, and physicians about preferences for and outcomes of treatments. Documenting existing advance directives was also one of this nurse's tasks. The Patient Self-Determination Act required that health care institutions inquire about and document existing advance directives at the time of hospital admission.
Measurement: Hospital resource use was derived from the Therapeutic Intensity Scoring System and hospital length of stay, converted into 1994 dollars.
Results: Chart documentation of existing advance directives at the time of study admission increased with both the PSDA and the SUPPORT intervention. We found that intervention patients were more likely to have pre-existing ADs documented. Despite this increase, there was no corresponding change in hospital resource use for those who died during the enrollment hospitalization. Replication of analyses from published studies using data from the block randomized controlled trial found that ADs documented by the third day of serious illness were associated with a 23% reduction in hospital resource use among control patients ($21,284 with ADs documented compared with $26,127 without, 95% CI 1-48% reduction). However, this association was not observed among intervention patients, who had more pre-existing ADs documented in the medical record. Intervention patients with early documentation of ADs showed a trend toward greater cost ($28,017 compared with $24,178 among those without AD documentation, 95% CI 0-25% increase). The rate of documentation and characteristics of those with documentation differed between control and intervention patients. Intervention patients were more likely (as reported by patient or surrogate interview) to have ADs documented in the medical record by the third day (55% vs 32%, P < .001). In contrast to intervention patients, control patients who were older, less wealthy, less educated, more likely to prefer to forgo CPR, and more likely to want life-sustaining treatment limited had their ADs documented. These associations were not found among intervention patients when comparison was made between those with and those without an AD documented in the medical record.
Conclusion: Increasing the documentation of pre-existing ADs was not associated with a reduction in hospital resource use. ADs documented without further intervention by the third day of a serious illness were associated with decreased hospital resource use. However, we did not find this association with an intervention that increased AD documentation. One potential explanation of these findings is that classification of those with an AD was based on cha