Association of Physician Orders for Life-Sustaining Treatment With Inpatient Antimicrobial Use at End of Life in Patients With Cancer

BACKGROUND: Antimicrobial utilization at end of life is common, but whether advance directives correlate with usage is unknown. We sought to determine whether Washington State Physician Orders for Life Sustaining Treatment (POLST) form completion or antimicrobial preferences documented therein correlate with subsequent inpatient antimicrobial prescribing at end of life. METHODS: This was a single-center, retrospective cohort study of adult patients at a cancer center who died between January 1, 2016, and June 30, 2019. We used negative binomial models adjusted for age, sex, and malignancy type to test the relationship between POLST form completion ≥30 days before death, antimicrobial preferences, and antimicrobial days of therapy (DOT) per 1000 inpatient-days in the last 30 days of life. RESULTS: Among 1295 eligible decedents with ≥1 inpatient-day during the last 30 days of life, 318 (24.6%) completed a POLST form. Of 318, 120 (37.7%) were completed ≥30 days before death, 35/120 (29.2%) specified limited antimicrobials, 55/120 (45.8%) specified full antimicrobial use, and 30/120 (25%) omitted antimicrobial preference. Eighty-three percent (1070/1295) received ≥1 inpatient antimicrobial. The median total and intravenous (IV) antimicrobial DOT/1000 inpatient-days were 1077 and 667. Patients specifying limited antimicrobials had significantly lower total antimicrobial DOT (adjusted incidence rate ratio [IRR], 0.68; 95% CI, 0.49–0.95; P = .02) and IV antimicrobial DOT (IRR, 0.57; 95% CI, 0.38–0.86; P = .008) compared with those without a POLST. CONCLUSIONS: Indicating a preference for limited antimicrobials on a POLST form ≥30 days before death may lead to less inpatient antimicrobial use in the last 30 days of life.