Benzodiazepine-related polysubstance use and hospital resource utilization in older trauma patients: a retrospective...

Benzodiazepine use among adults ≥50 years is increasing and frequently co-occurs with other substances, a pattern linked to trauma risk and greater hospital resource utilization. This study evaluated the impact of benzodiazepine-related polysubstance use on resource utilization in older trauma patients.

We conducted a retrospective cohort study of trauma patients aged ≥50 admitted to four US trauma centers (January 2016-July 2022). Patients were classified as positive for ≥2 substances including benzodiazepines (PSB+), positive for ≥2 substances excluding benzodiazepines (PSB-), or substance negative (SB-). Outcomes included urine drug screening (UDS) trends, benzodiazepine positivity, and the following hospital resource utilization outcomes: intensive care unit (ICU) admission, ventilation, transfusion, surgery, ICU length of stay (LOS) >4 days, hospital LOS >5 days, or in-hospital complications. Covariates were balanced using inverse probability weighting (IPW).

Of 24 045 older patients, 13% (n=3008) underwent UDS; 38% were substance positive. The final cohort (n=2201) included 158 (7%) PSB+, 181 (8%) PSB-, and 1862 (85%) SB- patients. UDS rates declined over time (p<0.001), while PSB+ use slightly increased (p=0.02). Compared with PSB-, PSB+ patients were older (median 60 years vs. 56 years, p<0.001), more often female (37% vs. 23%, p=0.007), and more likely to have falls (47% vs. 32%, p=0.04), high alcohol levels (68% vs. 26%, p=0.001), Glasgow Coma Scale score ≤8 (25% vs. 8%, p<0.001), and Injury Severity Score ≥16 (31% vs. 19%, p=0.02). Unadjusted analyses showed higher ICU admissions, ventilation, transfusions, and complications in PSB+ patients. After IPW, PSB+ remained associated with higher odds of ICU admission (OR 1.84, 95% CI 1.18 to 2.85, p=0.007) and transfusion (OR 1.87, 95% CI 1.04 to 3.39, p=0.04). Among patients aged ≥65, PSB+ conferred more than threefold higher ICU admission odds (OR 3.35, 95% CI 1.32 to 8.51, p=0.01).

Benzodiazepine-positive polysubstance use in older trauma patients is independently associated with higher odds of ICU-level care and transfusion, supporting early identification of this high-risk population.

Level IV, retrospective study.