Background: Given the increasing age and medical complexity of trauma patients, medical comanagement has been adopted as a strategy for high-risk patients. This study aimed to determine whether a geriatrics-focused hospitalist trauma comanagement program improves outcomes.Methods: A pre- and post-implementation study compared older adult trauma patients who were comanaged by a hospitalist with those prior to comanagement at a Level 1 trauma center. Criteria for comanagement included: age 65+, multiple comorbidities, and use of high-risk medications. Comanagement focused on geriatric trauma management guidelines. One-to-one propensity score matching (PSM) was performed based on age, gender, Injury Severity Score, Charlson comorbidity index, and initial admission to the intensive care unit (ICU). Outcomes included hospital mortality, length of stay (LOS), and orders for geriatrics-focused quality indicators. Differences were compared with the Wilcoxon Rank Sum test for continuous variables and chi- square or Fisher’s exact test for categorical variables.Results: From 792 control and 365 intervention patients, PSM resulted in 290 matched pairs. Three intervention group patients died compared to 14 in the control group (p=0.0068). Hospital LOS, 30-day readmission, ICU LOS, and ICU upgrades were not significantly different between groups. There was an overall trend toward improved geriatrics-focused quality indicators in the intervention group. Intervention group was less likely to be restrained (p=0.04), received earlier physical therapy (p=0.01), more doses of acetaminophen compared to control patients (p<0.0001), and more subcutaneous enoxaparin rather than heparin (p=0.0027).Discussion: Our main findings highlight the higher medical complexity and increased risks in older adult trauma patients, as well as the mortality reduction and adherence increase to geriatrics-focused quality indicators. Limitations of our study included use of a single center, the possibility of selection bias in analyzing historical data, and a low sample size, all of which may limit generalizability. Conclusions: Our study demonstrates that a geriatrics-focused hospitalist trauma comanagement program improves survival and quality of care.