Dementia as a Marker of Poor Outcome After Hip Hemiarthroplasty

PURPOSE: To evaluate the effect of baseline dementia on postoperative outcomes in hip fracture patients undergoing hemiarthroplasty. METHODS: A retrospective review was conducted of patients aged 55 years or older who underwent hemiarthroplasty for displaced femoral neck fracture (AO/OTA 31B) between 2012 and 2024 at a large urban academic institution. Dementia was identified by ICD-10 codes and confirmed by chart review. A 3:1 propensity score matched cohort was created using the Score for Trauma Triage in Geriatric and Middle-aged (STTGMA). Demographics and baseline characteristics were compared to ensure similarity. Outcomes included total complications, major and minor complications, periprosthetic dislocation, length of stay, ICU admission, discharge location, 30- and 90-day readmission, revision surgery, inpatient, and 30-day and 1-year mortality. RESULTS: A total of 1,030 patients were included, with 241 patients with dementia and 839 controls. After 3:1 STTGMA propensity matching, baseline characteristics were comparable (mean age 82.75 vs. 83.0 years, P = 0.065; Charlson Comorbidity Index 1.96 vs. 1.92, P = 0.42; STTGMA 0.022 vs. 0.020, P = 0.50). Patients with dementia had increased major complications (17.92% vs. 10.93%, P = 0.013), including sepsis (5.00% vs. 2.21%, P = 0.027), urinary tract infections (13.33% vs. 6.78%, P = 0.002), and hip hemiarthroplasty dislocations (6.25% vs. 2.21%, P = 0.002). Patients with dementia also had longer length of stay (7.84 ± 5.83 vs. 6.80 ± 2.24 days, P = 0.030), increased 30-day readmissions (15.83% vs. 8.85%, P < 0.001), increased 90-day readmission (20.00% vs. 11.76%, P < 0.001), and higher 1-year mortality (16.25% vs. 8.02%, P < 0.001). No differences were observed in pneumonia, stroke, myocardial infarction, cardiac arrest, venothromboembolism, acute kidney injury, anemia, and revision surgery. CONCLUSION: Dementia was associated with increased major complications, hip hemiarthroplasty dislocations, higher readmission, and mortality after hemiarthroplasty. These findings highlight the need for targeted perioperative planning and multidisciplinary care pathways in cognitively impaired patients.