Impact of Dementia on Outcomes Following Hemiarthroplasty for Femoral Neck Fracture: A National Database Study.

Background: Dementia poses an elevated risk of femoral neck fracture (FNF) in the elderly, often leading to the need for hemiarthroplasty. Yet, the outcomes of hemiarthroplasty in patients who have dementia remain uncertain. The purpose of this study was to assess whether dementia serves as a potential risk factor for outcomes following hemiarthroplasty.

Methods: Dementia patients who underwent hemiarthroplasty for FNF with at least 1 year of follow-up were identified using a national insurance database. A 1:1 matched control cohort of patients who do not have dementia was created for comparison. Logistic regression analyses were used to evaluate the rates of complications between the two cohorts. A total of 89,072 patients, of whom half have dementia and half do not, undergoing hemiarthroplasty for FNF were identified.

Results: Aside from increased risks of medical complications (P < 0.01), including pneumonia, cerebrovascular accident, acute kidney injury, urinary tract infection, and sepsis, within 90 days, dementia patients also demonstrated higher rates of surgical complications within 1 year, such as dislocation (odds ratio (OR) 1.87, 95% confidence interval (CI) 1.71 to 2.04), periprosthetic fractures (OR 1.29, 95% CI 1.16 to 1.45), and revision (OR 1.23, 95% CI 1.10 to 1.36). On the other hand, dementia patients displayed slightly reduced rates of 90-day deep vein thrombosis and pulmonary embolism. However, no significant increase was found in transfusion, myocardial infarction, wound complications, periprosthetic joint infection, or aseptic loosening between the two cohorts. Additionally, patients who have dementia demonstrated a higher likelihood of 90-day emergency department visits, whereas rates of 90-day hospital readmission remained similar.

Conclusions: Although dementia patients do not exhibit an elevated risk of periprosthetic joint infection, or aseptic loosening, they are more prone to experiencing higher risks of prosthetic dislocation, periprosthetic fracture, and revision. Furthermore, specific medical complications tend to be more prevalent among individuals who have dementia.